fix(web): follow composer and rail layout

Plan rows are omitted from the transcript in both clients and rendered
in a separate plan rail/status line, not as a transcript checklist.

CLAUDE.md

@@ -36,10 +36,16 @@ optional.
 
 ## Where the work is
 
-Linear project **Maestro** under team **Naps62**.
+Gitea issues on [`naps62/maestro`](https://git.naps.pt/naps62/maestro), grouped
+into milestones.
 
-`.claude/linear.json` wires `/yolo` and `/work` to this project — they pick from
-"available now" (status backlog/pending, not blocked).
+`.claude/linear.json` (legacy filename, `tracker: gitea`) wires `/yolo` and
+`/work` to that tracker — they pick from open, unassigned issues whose
+dependencies are all closed. `/blitz <milestone>` sweeps a whole milestone.
+
+Labels carry one value per axis: `area/*`, `type/*`, `difficulty/*`.
+`difficulty` drives model selection downstream, so it tracks the shape of the
+work, not its size.
 
 ## Repo layout
 
@@ -72,11 +78,26 @@ before changing anything that creates or removes one.
 sidebars — line layout, activity colours, duration format, state precedence.
 Read it before changing sidebar rendering.
 
+`docs/PREVIEW.md` is the contract for what the content pane shows while the
+operator moves the sidebar highlight — what a preview may touch, what ends it,
+what commits it. Read it before changing sidebar-driven navigation.
+
 `docs/RESTART.md` is the contract for what clients do when the daemon restarts
 or is upgraded under them — the build stamp on `/api/info`, the status
 indicator's states, the blocking overlay, grace and poll timings. Read it
 before changing reconnect behaviour on either client.
 
+`docs/COMMAND-BAR.md` is the contract for the `ctrl-k` command bar in both
+clients — how it opens, the sigils, the key model, the match-and-rank algorithm
+the two matchers must agree on, and the fixture table they are tested against.
+Read it before changing either bar or either matcher.
+
+`docs/STRUCTURED-VIEW.md` is the contract for a structured session (an agent
+run as a daemon child over ACP instead of in a tmux pane) — the eight
+transcript row kinds, the two projections and their cursor/replay semantics,
+the handshake and declined capabilities, and the approval nonce rules. Read
+it before changing anything that renders a structured session.
+
 `nix run .#dev` (or `just dev`) brings up the whole local stack under
 process-compose: a debug daemon on 127.0.0.1:7071, then Vite on :5173 once the
 daemon answers `/api/info`. The SPA proxies `/api/*` back to the daemon, so only

Cargo.toml

@@ -10,6 +10,7 @@ repository = "https://git.naps.pt/naps62/maestro"
 publish = false
 
 [workspace.dependencies]
+agent-client-protocol = { version = "2.1", features = ["unstable_tool_call_name"] }
 axum = { version = "0.7", features = ["ws"] }
 chrono = { version = "0.4", default-features = false, features = ["clock", "serde"] }
 clap = { version = "4.5", features = ["derive", "env"] }
@@ -17,6 +18,7 @@ crossterm = { version = "0.28", features = ["event-stream"] }
 dirs = "5"
 futures-util = { version = "0.3", default-features = false, features = ["sink", "std"] }
 libc = "0.2"
+maestro-acp = { path = "crates/maestro-acp" }
 maestro-config = { path = "crates/maestro-config" }
 # `default-features = false` so each consumer opts into `haiku-autoname`
 # through its own feature of the same name (#131); a workspace entry that
@@ -38,9 +40,11 @@ tempfile = "3"
 thiserror = "1"
 tokio = { version = "1", features = ["macros", "rt-multi-thread", "sync", "time", "net", "io-util", "fs", "signal", "process"] }
 tokio-tungstenite = "0.21"
+tokio-util = { version = "0.7", features = ["compat"] }
 toml = "0.8"
 tracing = "0.1"
 tracing-subscriber = { version = "0.3", features = ["env-filter"] }
+unicode-width = "0.1"
 uuid = { version = "1", features = ["v4", "serde"] }
 ratatui = "0.28"
 vt100 = "0.15"

crates/maestro-acp/Cargo.toml

@@ -0,0 +1,20 @@
+[package]
+name = "maestro-acp"
+version.workspace = true
+edition.workspace = true
+license.workspace = true
+repository.workspace = true
+publish.workspace = true
+description = "ACP client role: one claude-code-acp child per structured session"
+
+[dependencies]
+agent-client-protocol.workspace = true
+libc.workspace = true
+serde_json.workspace = true
+thiserror.workspace = true
+tokio.workspace = true
+tokio-util.workspace = true
+tracing.workspace = true
+
+[dev-dependencies]
+tempfile.workspace = true

crates/maestro-acp/src/lib.rs

@@ -0,0 +1,721 @@
+//! ACP client role for the daemon (#134): one `claude-code-acp` child per
+//! structured session.
+//!
+//! The daemon is the client; the adapter is the agent. [`spawn`] starts the
+//! adapter as a child process with stdio pipes, in the session's `cwd` with
+//! the session's env, runs the `initialize` + `session/new` handshake, and
+//! hands back an [`AcpSession`] that owns the connection for the life of the
+//! session.
+//!
+//! **The handshake declares almost nothing.** `initialize` reports
+//! `fs.readTextFile`, `fs.writeTextFile` and `terminal` as `false`, so the
+//! adapter uses Claude Code's own Read / Write / Bash instead of asking the
+//! daemon to act on its behalf — exactly what already happens in the
+//! terminal view. `session/request_permission` is the one client method that
+//! gets a real implementation, in #139; here it is a stub that declines.
+//!
+//! Every `session/update` notification the adapter sends lands on an
+//! unbounded channel the session owns ([`AcpSession::take_updates`]). Nothing
+//! is dropped while nobody reads: #135 takes the receiver and persists each
+//! notification to the per-session event log before broadcasting it.
+//!
+//! A respawn after a daemon restart sets [`SpawnConfig::load_session`] and
+//! the handshake runs `session/load` with the stored id instead of
+//! `session/new`. The history the agent streams back while that request is
+//! in flight is *not* delivered: the daemon's event log already holds it,
+//! and replaying it would double every line.
+//!
+//! The child is a child of the daemon, full stop. It shares the daemon's
+//! process group, is marked to receive `SIGTERM` when the daemon dies
+//! (`PR_SET_PDEATHSIG` on Linux), and [`AcpSession::terminate`] is what both
+//! `DELETE /api/sessions/:id` and daemon shutdown call: `session/cancel`, a
+//! short wait, then `SIGTERM`, then `SIGKILL` as the last resort.
+
+#![deny(missing_debug_implementations)]
+
+use std::collections::{HashMap, VecDeque};
+use std::ffi::OsString;
+use std::path::{Path, PathBuf};
+use std::process::{ExitStatus, Stdio};
+use std::sync::atomic::{AtomicBool, Ordering};
+use std::sync::{Arc, Mutex};
+use std::time::Duration;
+
+use agent_client_protocol::schema::v1::{
+    CancelNotification, ClientCapabilities, ContentBlock, FileSystemCapabilities, Implementation,
+    InitializeRequest, LoadSessionRequest, NewSessionRequest, PromptRequest,
+    RequestPermissionOutcome, RequestPermissionRequest, RequestPermissionResponse, SessionId,
+    SessionNotification,
+};
+use agent_client_protocol::schema::ProtocolVersion;
+use agent_client_protocol::{ByteStreams, Client};
+use tokio::io::AsyncBufReadExt;
+use tokio::sync::{mpsc, oneshot, watch};
+use tokio_util::compat::{TokioAsyncReadCompatExt, TokioAsyncWriteCompatExt};
+
+pub use agent_client_protocol::schema::v1 as schema;
+
+/// The adapter binary, resolved on `PATH`.
+pub const ADAPTER_BIN: &str = "claude-code-acp";
+
+/// How to install the adapter when it is missing. Named in the error so an
+/// operator staring at a failed session knows what to run.
+pub const INSTALL_COMMAND: &str =
+    "npm install -g --prefix ~/.local @zed-industries/claude-code-acp";
+
+/// How long `initialize` + `session/new` may take before the spawn is
+/// declared failed. The real adapter boots a node process and the Claude
+/// Code SDK behind it; a slow machine takes seconds, never a minute.
+pub const HANDSHAKE_TIMEOUT: Duration = Duration::from_secs(60);
+
+/// How long [`AcpSession::terminate`] waits after `session/cancel` before
+/// sending `SIGTERM`. Cancel is a courtesy that lets the adapter finish the
+/// turn it is on; the signal is what actually ends it.
+pub const CANCEL_GRACE: Duration = Duration::from_millis(500);
+
+/// How long [`AcpSession::terminate`] waits after `SIGTERM` before `SIGKILL`.
+pub const TERM_GRACE: Duration = Duration::from_secs(2);
+
+/// Bytes of the child's stderr kept for the failure message.
+const STDERR_TAIL_BYTES: usize = 4096;
+
+/// What [`spawn`] needs to start one adapter.
+#[derive(Debug, Clone)]
+pub struct SpawnConfig {
+    /// Working directory of the child and `cwd` of `session/new`.
+    pub cwd: PathBuf,
+    /// Environment laid over the daemon's own for the child. A `PATH` in
+    /// here is also what the adapter is resolved against, since that is the
+    /// `PATH` the child would see.
+    pub env: HashMap<String, String>,
+    /// Upper bound on the handshake; [`HANDSHAKE_TIMEOUT`] by default.
+    pub handshake_timeout: Duration,
+    /// An existing ACP session id to resume with `session/load` (#135)
+    /// instead of opening a fresh one. The adapter must advertise
+    /// `loadSession`; the handshake fails otherwise.
+    pub load_session: Option<String>,
+}
+
+impl SpawnConfig {
+    pub fn new(cwd: impl Into<PathBuf>, env: HashMap<String, String>) -> Self {
+        Self {
+            cwd: cwd.into(),
+            env,
+            handshake_timeout: HANDSHAKE_TIMEOUT,
+            load_session: None,
+        }
+    }
+
+    /// Resume `session_id` with `session/load` instead of `session/new`.
+    pub fn load_session(mut self, session_id: impl Into<String>) -> Self {
+        self.load_session = Some(session_id.into());
+        self
+    }
+}
+
+/// A blocked ACP permission request delivered to the daemon.
+#[derive(Debug)]
+pub struct PermissionRequest {
+    /// The prompt turn that was active when ACP delivered this callback.
+    pub turn: u64,
+    pub request: RequestPermissionRequest,
+    pub response: oneshot::Sender<RequestPermissionOutcome>,
+}
+
+#[derive(Debug, thiserror::Error)]
+pub enum AcpError {
+    /// The adapter is not on `PATH`. The message names the install command
+    /// so the failed session is actionable rather than silently dead.
+    #[error("{ADAPTER_BIN} not found on PATH; install it with: {INSTALL_COMMAND}")]
+    AdapterMissing,
+    #[error("failed to start {ADAPTER_BIN}: {0}")]
+    Spawn(#[source] std::io::Error),
+    /// The adapter answered the handshake with an error.
+    #[error("ACP handshake failed: {0}")]
+    Handshake(String),
+    /// The adapter went away before the handshake finished. Carries the
+    /// tail of its stderr, which is where a missing Claude login shows up.
+    #[error("{ADAPTER_BIN} exited during the ACP handshake ({status}){stderr}")]
+    ExitedEarly { status: String, stderr: String },
+    #[error("ACP handshake timed out after {0:?}")]
+    HandshakeTimeout(Duration),
+}
+
+/// Resolve [`ADAPTER_BIN`] against the `PATH` the child would run with: the
+/// session env's `PATH` when it sets one, the daemon's own otherwise.
+pub fn resolve_adapter(env: &HashMap<String, String>) -> Option<PathBuf> {
+    let path: OsString = match env.get("PATH") {
+        Some(p) => OsString::from(p),
+        None => std::env::var_os("PATH")?,
+    };
+    std::env::split_paths(&path)
+        .filter(|dir| !dir.as_os_str().is_empty())
+        .map(|dir| dir.join(ADAPTER_BIN))
+        .find(|candidate| is_executable(candidate))
+}
+
+fn is_executable(path: &Path) -> bool {
+    use std::os::unix::fs::PermissionsExt;
+    std::fs::metadata(path)
+        .map(|m| m.is_file() && m.permissions().mode() & 0o111 != 0)
+        .unwrap_or(false)
+}
+
+enum Command {
+    Cancel,
+    Prompt {
+        text: String,
+        turn: u64,
+        done: oneshot::Sender<Result<(), String>>,
+    },
+    Close,
+}
+
+enum ChildCommand {
+    Signal(libc::c_int),
+    Reap(oneshot::Sender<bool>),
+}
+
+#[derive(Debug, Default)]
+struct PermissionTurnState {
+    active: Option<u64>,
+}
+
+impl PermissionTurnState {
+    fn begin(&mut self, turn: u64) {
+        self.active = Some(turn);
+    }
+
+    fn cancel_active(&mut self) {
+        self.active = None;
+    }
+
+    fn finish(&mut self, turn: u64) {
+        if self.active == Some(turn) {
+            self.active = None;
+        }
+    }
+
+    fn callback_turn(&self) -> Option<u64> {
+        self.active
+    }
+}
+
+/// Why the handshake did not produce a session id.
+enum ReadyError {
+    /// The adapter answered with an error.
+    Handshake(String),
+    /// The transport closed under the request: the child is gone.
+    Closed,
+}
+
+fn ready_error(e: agent_client_protocol::Error) -> ReadyError {
+    if agent_client_protocol::is_incoming_transport_closed(&e) {
+        ReadyError::Closed
+    } else {
+        ReadyError::Handshake(e.to_string())
+    }
+}
+
+/// A live ACP connection to one adapter child. Dropping it sends `SIGTERM`
+/// if the child is still running; [`AcpSession::terminate`] is the polite
+/// version.
+#[derive(Debug)]
+pub struct AcpSession {
+    session_id: String,
+    pid: u32,
+    commands: mpsc::UnboundedSender<Command>,
+    child_commands: mpsc::UnboundedSender<ChildCommand>,
+    updates: Mutex<Option<mpsc::UnboundedReceiver<SessionNotification>>>,
+    permission_requests: Mutex<Option<mpsc::UnboundedReceiver<PermissionRequest>>>,
+    exit: watch::Receiver<Option<ExitStatus>>,
+}
+
+impl AcpSession {
+    /// The id `session/new` returned. What a respawn passes to
+    /// `session/load` (#135).
+    pub fn session_id(&self) -> &str {
+        &self.session_id
+    }
+
+    /// The adapter's pid.
+    pub fn pid(&self) -> u32 {
+        self.pid
+    }
+
+    /// Whether the child has been reaped.
+    pub fn has_exited(&self) -> bool {
+        self.exit.borrow().is_some()
+    }
+
+    /// Reap the child if it has already exited.
+    pub async fn reap_if_exited(&self) -> bool {
+        if self.has_exited() {
+            return true;
+        }
+        let (sent, received) = oneshot::channel();
+        if self.child_commands.send(ChildCommand::Reap(sent)).is_err() {
+            return self.has_exited();
+        }
+        received.await.unwrap_or_else(|_| self.has_exited())
+    }
+
+    /// Wait for the child to exit.
+    pub async fn wait(&self) -> Option<ExitStatus> {
+        wait_exit(&self.exit).await
+    }
+
+    /// The stream of raw `session/update` notifications, handed out once.
+    /// Notifications that arrived before the take are still queued on it.
+    pub fn take_updates(&self) -> Option<mpsc::UnboundedReceiver<SessionNotification>> {
+        self.updates.lock().expect("updates mutex").take()
+    }
+
+    pub fn take_permission_requests(&self) -> Option<mpsc::UnboundedReceiver<PermissionRequest>> {
+        self.permission_requests
+            .lock()
+            .expect("permission requests")
+            .take()
+    }
+
+    /// Send `session/cancel`. Fire-and-forget: a closed connection means the
+    /// child is already gone, which is the outcome cancel was after.
+    pub fn cancel(&self) {
+        let _ = self.commands.send(Command::Cancel);
+    }
+
+    /// Send a user prompt and receive completion once the agent ends the turn.
+    pub fn prompt(
+        &self,
+        text: String,
+        turn: u64,
+    ) -> Result<oneshot::Receiver<Result<(), String>>, String> {
+        let (done_tx, done_rx) = oneshot::channel();
+        self.commands
+            .send(Command::Prompt {
+                text,
+                turn,
+                done: done_tx,
+            })
+            .map_err(|_| "ACP connection is closed".to_string())?;
+        Ok(done_rx)
+    }
+
+    /// End the child: `session/cancel`, wait `cancel_grace`, `SIGTERM`, wait
+    /// `term_grace`, `SIGKILL`. Returns once the child has been reaped.
+    pub async fn terminate(&self, cancel_grace: Duration, term_grace: Duration) {
+        self.cancel();
+        if tokio::time::timeout(cancel_grace, self.wait())
+            .await
+            .is_ok()
+        {
+            return;
+        }
+        self.signal(libc::SIGTERM);
+        if tokio::time::timeout(term_grace, self.wait()).await.is_ok() {
+            return;
+        }
+        tracing::warn!(
+            pid = self.pid,
+            "{ADAPTER_BIN} ignored SIGTERM; sending SIGKILL"
+        );
+        self.signal(libc::SIGKILL);
+        let _ = self.commands.send(Command::Close);
+        self.wait().await;
+    }
+
+    fn signal(&self, sig: libc::c_int) {
+        let _ = self.child_commands.send(ChildCommand::Signal(sig));
+    }
+}
+
+impl Drop for AcpSession {
+    fn drop(&mut self) {
+        self.signal(libc::SIGTERM);
+        let _ = self.commands.send(Command::Close);
+    }
+}
+
+/// Start the adapter for one session and run the handshake.
+///
+/// Fails without a running child: on any error the process is already
+/// signalled, so a failed session never leaves a stray adapter behind.
+pub async fn spawn(config: SpawnConfig) -> Result<AcpSession, AcpError> {
+    let adapter = resolve_adapter(&config.env).ok_or(AcpError::AdapterMissing)?;
+
+    let mut cmd = tokio::process::Command::new(&adapter);
+    cmd.current_dir(&config.cwd)
+        .envs(&config.env)
+        // Claude Code refuses to start when it thinks it is nested inside
+        // another Claude Code session; a daemon launched from one would
+        // otherwise never get a structured session up.
+        .env_remove("CLAUDECODE")
+        .stdin(Stdio::piped())
+        .stdout(Stdio::piped())
+        .stderr(Stdio::piped())
+        // If the daemon is dropped without a graceful shutdown the runtime
+        // still tears the task holding this `Child` down, and that kills it.
+        .kill_on_drop(true);
+    #[cfg(target_os = "linux")]
+    {
+        // Same process group as the daemon (no setpgid), and SIGTERM when the
+        // daemon dies however it dies: an agent that outlives its daemon is
+        // exactly the orphan #134 rules out.
+        // SAFETY: prctl is async-signal-safe and touches no shared state.
+        unsafe {
+            cmd.pre_exec(|| {
+                libc::prctl(libc::PR_SET_PDEATHSIG, libc::SIGTERM);
+                Ok(())
+            });
+        }
+    }
+    let mut child = cmd.spawn().map_err(AcpError::Spawn)?;
+    let pid = child.id().expect("child pid is known before wait");
+    let stdin = child.stdin.take().expect("piped stdin");
+    let stdout = child.stdout.take().expect("piped stdout");
+    let stderr = child.stderr.take().expect("piped stderr");
+
+    let stderr_tail = Arc::new(Mutex::new(VecDeque::<u8>::new()));
+    tokio::spawn(drain_stderr(stderr, pid, stderr_tail.clone()));
+
+    let (exit_tx, exit_rx) = watch::channel(None);
+    let (child_commands_tx, child_commands_rx) = mpsc::unbounded_channel();
+    tokio::spawn(supervise_child(child, pid, child_commands_rx, exit_tx));
+
+    let (updates_tx, updates_rx) = mpsc::unbounded_channel();
+    let (permission_tx, permission_rx) = mpsc::unbounded_channel();
+    let (commands_tx, commands_rx) = mpsc::unbounded_channel();
+    let (ready_tx, ready_rx) = oneshot::channel();
+    let transport = ByteStreams::new(stdin.compat_write(), stdout.compat());
+    tokio::spawn(run_connection(
+        transport,
+        config.cwd.clone(),
+        config.load_session.clone(),
+        updates_tx,
+        permission_tx,
+        commands_rx,
+        ready_tx,
+    ));
+
+    let outcome = tokio::time::timeout(config.handshake_timeout, ready_rx).await;
+    let failure = match outcome {
+        Ok(Ok(Ok(session_id))) => {
+            return Ok(AcpSession {
+                session_id,
+                pid,
+                commands: commands_tx,
+                child_commands: child_commands_tx,
+                updates: Mutex::new(Some(updates_rx)),
+                permission_requests: Mutex::new(Some(permission_rx)),
+                exit: exit_rx,
+            });
+        }
+        Ok(Ok(Err(ReadyError::Handshake(message)))) => AcpError::Handshake(message),
+        Ok(Ok(Err(ReadyError::Closed))) | Ok(Err(_)) => {
+            // The connection ended before the handshake did: the child went
+            // away. Reap it so the status is real, then report.
+            let status = wait_exit(&exit_rx).await;
+            let stderr = {
+                let mut tail = stderr_tail.lock().expect("stderr tail");
+                tail.make_contiguous();
+                String::from_utf8_lossy(tail.as_slices().0)
+                    .trim()
+                    .to_string()
+            };
+            AcpError::ExitedEarly {
+                status: status.map_or_else(|| "unknown status".into(), |s| s.to_string()),
+                stderr: if stderr.is_empty() {
+                    String::new()
+                } else {
+                    format!(": {stderr}")
+                },
+            }
+        }
+        Err(_) => AcpError::HandshakeTimeout(config.handshake_timeout),
+    };
+    // No half-started adapter survives a failed spawn.
+    let _ = commands_tx.send(Command::Close);
+    let _ = child_commands_tx.send(ChildCommand::Signal(libc::SIGTERM));
+    if tokio::time::timeout(TERM_GRACE, wait_exit(&exit_rx))
+        .await
+        .is_err()
+    {
+        let _ = child_commands_tx.send(ChildCommand::Signal(libc::SIGKILL));
+        wait_exit(&exit_rx).await;
+    }
+    Err(failure)
+}
+
+async fn wait_exit(exit: &watch::Receiver<Option<ExitStatus>>) -> Option<ExitStatus> {
+    let mut exit = exit.clone();
+    let status = exit.wait_for(|s| s.is_some()).await.ok()?;
+    *status
+}
+
+async fn supervise_child(
+    mut child: tokio::process::Child,
+    pid: u32,
+    mut commands: mpsc::UnboundedReceiver<ChildCommand>,
+    exit_tx: watch::Sender<Option<ExitStatus>>,
+) {
+    loop {
+        tokio::select! {
+            status = child.wait() => {
+                let status = status.ok();
+                tracing::debug!(pid, ?status, "{ADAPTER_BIN} exited");
+                let _ = exit_tx.send(status);
+                return;
+            }
+            command = commands.recv() => match command {
+                Some(ChildCommand::Signal(sig)) => {
+                    // This task alone owns `child`. It cannot reap the child
+                    // between receiving this command and sending the signal,
+                    // so its PID cannot be reused in that window.
+                    unsafe { libc::kill(pid as libc::pid_t, sig) };
+                }
+                Some(ChildCommand::Reap(done)) => match child.try_wait() {
+                    Ok(Some(status)) => {
+                        let _ = done.send(true);
+                        tracing::debug!(pid, ?status, "{ADAPTER_BIN} exited");
+                        let _ = exit_tx.send(Some(status));
+                        return;
+                    }
+                    Ok(None) => {
+                        let _ = done.send(false);
+                    }
+                    Err(error) => {
+                        tracing::warn!(pid, %error, "could not reap {ADAPTER_BIN}");
+                        let _ = done.send(false);
+                    }
+                },
+                None => {
+                    // The session vanished without a command receiver. This
+                    // task still owns the unreaped child, so this cannot hit
+                    // a reused PID.
+                    unsafe { libc::kill(pid as libc::pid_t, libc::SIGTERM) };
+                    let status = child.wait().await.ok();
+                    tracing::debug!(pid, ?status, "{ADAPTER_BIN} exited");
+                    let _ = exit_tx.send(status);
+                    return;
+                }
+            },
+        }
+    }
+}
+
+/// The capabilities the daemon declares: none of the filesystem or terminal
+/// surface, so the adapter falls back to Claude Code's own tools.
+fn client_capabilities() -> ClientCapabilities {
+    ClientCapabilities::new()
+        .fs(FileSystemCapabilities::new()
+            .read_text_file(false)
+            .write_text_file(false))
+        .terminal(false)
+}
+
+async fn run_connection<T>(
+    transport: T,
+    cwd: PathBuf,
+    load_session: Option<String>,
+    updates_tx: mpsc::UnboundedSender<SessionNotification>,
+    permission_requests: mpsc::UnboundedSender<PermissionRequest>,
+    mut commands_rx: mpsc::UnboundedReceiver<Command>,
+    ready_tx: oneshot::Sender<Result<String, ReadyError>>,
+) where
+    T: agent_client_protocol::ConnectTo<Client> + 'static,
+{
+    // Set while `session/load` is in flight. Notification handlers run in
+    // the dispatch loop, in arrival order, so everything the agent streams
+    // before its load response sees the flag up and is dropped: that is the
+    // history the event log already holds (#135).
+    let replaying = Arc::new(AtomicBool::new(false));
+    let replaying_seen = replaying.clone();
+    // ACP callbacks have no turn id. The daemon never queues a later prompt
+    // until a cancelled prompt settles, so this active turn is unambiguous.
+    let permission_turn = Arc::new(Mutex::new(PermissionTurnState::default()));
+    let permission_turn_seen = permission_turn.clone();
+    let result = Client
+        .builder()
+        .name("maestro")
+        .on_receive_notification(
+            async move |notification: SessionNotification, _cx| {
+                if replaying_seen.load(Ordering::SeqCst) {
+                    tracing::trace!("dropping replayed notification during session/load");
+                    return Ok(());
+                }
+                // A dropped receiver only means nobody wants updates any more.
+                let _ = updates_tx.send(notification);
+                Ok(())
+            },
+            agent_client_protocol::on_receive_notification!(),
+        )
+        .on_receive_request(
+            async move |request: RequestPermissionRequest, responder, _cx| {
+                let turn = permission_turn_seen
+                    .lock()
+                    .expect("permission turn state")
+                    .callback_turn();
+                let Some(turn) = turn else {
+                    return responder.respond(RequestPermissionResponse::new(
+                        RequestPermissionOutcome::Cancelled,
+                    ));
+                };
+                let (response, received) = oneshot::channel();
+                if permission_requests
+                    .send(PermissionRequest {
+                        turn,
+                        request,
+                        response,
+                    })
+                    .is_err()
+                {
+                    return responder.respond(RequestPermissionResponse::new(
+                        RequestPermissionOutcome::Cancelled,
+                    ));
+                }
+                let outcome = received.await.unwrap_or(RequestPermissionOutcome::Cancelled);
+                responder.respond(RequestPermissionResponse::new(outcome))
+            },
+            agent_client_protocol::on_receive_request!(),
+        )
+        .connect_with(transport, async move |cx| {
+            let init = InitializeRequest::new(ProtocolVersion::V1)
+                .client_capabilities(client_capabilities())
+                .client_info(Implementation::new("maestro", env!("CARGO_PKG_VERSION")));
+            let initialized = match cx.send_request(init).block_task().await {
+                Ok(r) => r,
+                Err(e) => {
+                    let _ = ready_tx.send(Err(ready_error(e)));
+                    return Ok(());
+                }
+            };
+            let session_id = match load_session {
+                Some(existing) => {
+                    if !initialized.agent_capabilities.load_session {
+                        let _ = ready_tx.send(Err(ReadyError::Handshake(format!(
+                            "{ADAPTER_BIN} does not advertise loadSession; cannot resume session {existing}"
+                        ))));
+                        return Ok(());
+                    }
+                    replaying.store(true, Ordering::SeqCst);
+                    let (loaded_tx, loaded_rx) = oneshot::channel();
+                    let replaying_done = replaying.clone();
+                    if let Err(e) = cx
+                        .send_request(LoadSessionRequest::new(existing.clone(), cwd))
+                        .on_receiving_result(move |result| {
+                            replaying_done.store(false, Ordering::SeqCst);
+                            async move {
+                                let _ = loaded_tx.send(result);
+                                Ok(())
+                            }
+                        })
+                    {
+                        let _ = ready_tx.send(Err(ready_error(e)));
+                        return Ok(());
+                    }
+                    match loaded_rx.await {
+                        Ok(Ok(_)) => {}
+                        Ok(Err(e)) => {
+                            let _ = ready_tx.send(Err(ready_error(e)));
+                            return Ok(());
+                        }
+                        Err(_) => {
+                            let _ = ready_tx.send(Err(ReadyError::Handshake(
+                                "session/load response was not delivered".into(),
+                            )));
+                            return Ok(());
+                        }
+                    }
+                    existing
+                }
+                None => match cx
+                    .send_request(NewSessionRequest::new(cwd))
+                    .block_task()
+                    .await
+                {
+                    Ok(created) => created.session_id.0.to_string(),
+                    Err(e) => {
+                        let _ = ready_tx.send(Err(ready_error(e)));
+                        return Ok(());
+                    }
+                },
+            };
+            let _ = ready_tx.send(Ok(session_id.clone()));
+
+            loop {
+                tokio::select! {
+                    cmd = commands_rx.recv() => match cmd {
+                        Some(Command::Cancel) => {
+                            permission_turn
+                                .lock()
+                                .expect("permission turn state")
+                                .cancel_active();
+                            let _ = cx.send_notification(CancelNotification::new(
+                                SessionId::new(session_id.as_str()),
+                            ));
+                        }
+                        Some(Command::Prompt { text, turn, done }) => {
+                            permission_turn
+                                .lock()
+                                .expect("permission turn state")
+                                .begin(turn);
+                            let request = PromptRequest::new(
+                                SessionId::new(session_id.as_str()),
+                                vec![ContentBlock::from(text)],
+                            );
+                            let done = Arc::new(Mutex::new(Some(done)));
+                            let callback_done = done.clone();
+                            let callback_turn = permission_turn.clone();
+                            if let Err(error) = cx.send_request(request).on_receiving_result(move |result| {
+                                let callback_done = callback_done.clone();
+                                let callback_turn = callback_turn.clone();
+                                async move {
+                                    callback_turn
+                                        .lock()
+                                        .expect("permission turn state")
+                                        .finish(turn);
+                                    if let Some(done) = callback_done.lock().expect("prompt sender").take() {
+                                        let _ = done.send(result.map(|_| ()).map_err(|e| e.to_string()));
+                                    }
+                                    Ok(())
+                                }
+                            }) {
+                                permission_turn
+                                    .lock()
+                                    .expect("permission turn state")
+                                    .finish(turn);
+                                if let Some(done) = done.lock().expect("prompt sender").take() {
+                                    let _ = done.send(Err(error.to_string()));
+                                }
+                            }
+                        }
+                        Some(Command::Close) | None => break,
+                    },
+                    _ = cx.incoming_closed() => break,
+                }
+            }
+            Ok(())
+        })
+        .await;
+    if let Err(e) = result {
+        tracing::debug!(error = %e, "ACP connection ended with an error");
+    }
+}
+
+async fn drain_stderr(
+    stderr: tokio::process::ChildStderr,
+    pid: u32,
+    tail: Arc<Mutex<VecDeque<u8>>>,
+) {
+    let mut lines = tokio::io::BufReader::new(stderr).lines();
+    while let Ok(Some(line)) = lines.next_line().await {
+        tracing::debug!(pid, "{ADAPTER_BIN}: {line}");
+        let mut tail = tail.lock().expect("stderr tail");
+        tail.extend(line.as_bytes());
+        tail.push_back(b'\n');
+        while tail.len() > STDERR_TAIL_BYTES {
+            tail.pop_front();
+        }
+        tail.make_contiguous();
+    }
+}

crates/maestro-acp/tests/fake_acp_agent.py

@@ -0,0 +1,211 @@
+#!/usr/bin/env python3
+"""A deterministic stand-in for `claude-code-acp` (#134).
+
+Speaks just enough JSON-RPC over stdio for the daemon's handshake:
+answers `initialize` and `session/new`, logs every method it receives, and
+exits on SIGTERM. Tests point `PATH` at a directory holding this file under
+the adapter's name, so the real adapter (which needs Claude auth and is
+slow) never runs in the deterministic suite.
+
+Environment knobs, all optional:
+
+  FAKE_ACP_LOG            append one line per event to this file:
+                            start pid=<pid> cwd=<cwd>
+                            env <NAME>=<value>       (for FAKE_ACP_ECHO_ENV)
+                            caps <json of clientCapabilities>
+                            recv <method>
+                            signal SIGTERM
+  FAKE_ACP_ECHO_ENV       name of one env var to log at start
+  FAKE_ACP_INIT_FAIL=1    answer `initialize` with a JSON-RPC error
+  FAKE_ACP_DELAY_SESSION_NEW_MS=n  wait n milliseconds before answering
+                             `session/new`
+  FAKE_ACP_EXIT_AFTER_NEW=1  exit 0 right after answering `session/new`
+  FAKE_ACP_EXIT_ON_CANCEL=1  exit 0 on `session/cancel` (default: keep running
+                             so the SIGTERM path is exercised)
+  FAKE_ACP_IGNORE_EOF=1      keep running after stdin closes, until signalled
+  FAKE_ACP_EMIT_ON_CANCEL=1  emit a final notification before handling cancel
+  FAKE_ACP_CANCEL_SETTLES=1  complete the outstanding prompt on cancel
+  FAKE_ACP_NO_LOAD=1      advertise `loadSession: false`
+  FAKE_ACP_LOAD_REPLAY=n  on `session/load`, replay n `agent_message_chunk`
+                            notifications ("replayed <i>") before answering,
+                            the way a real agent streams history back
+  FAKE_ACP_LOAD_FAIL=1    answer `session/load` with a JSON-RPC error
+  FAKE_ACP_DELAY_PROMPT_MS=n  wait before answering `session/prompt`
+  FAKE_ACP_PROMPT_FAIL=1  answer every `session/prompt` with a JSON-RPC error
+  FAKE_ACP_PROMPT_FAIL_ONCE=1  answer only the first `session/prompt` with a
+                             JSON-RPC error
+  FAKE_ACP_PERMISSION_AFTER_CANCEL=1  defer the first prompt's permission
+                             callback until a later prompt
+
+Signals: SIGUSR1 emits one `agent_message_chunk` notification ("tick <n>",
+counting from 1) and logs `emit tick <n>`, so a test can make the agent
+speak on demand (#135).
+"""
+import json
+import os
+import signal
+import sys
+import time
+
+LOG = os.environ.get("FAKE_ACP_LOG")
+
+
+def log(line):
+    if not LOG:
+        return
+    with open(LOG, "a") as f:
+        f.write(line + "\n")
+        f.flush()
+
+
+def send(obj):
+    sys.stdout.write(json.dumps(obj) + "\n")
+    sys.stdout.flush()
+
+
+def on_sigterm(_signum, _frame):
+    log("signal SIGTERM")
+    sys.exit(0)
+
+
+signal.signal(signal.SIGTERM, on_sigterm)
+
+session_id = f"fake-{os.getpid()}"
+ticks = 0
+prompt_failures = 0
+pending_prompt_id = None
+pending_permission_id = None
+delayed_permission = False
+
+
+def chunk(text):
+    return {"jsonrpc": "2.0", "method": "session/update", "params": {
+        "sessionId": session_id,
+        "update": {"sessionUpdate": "agent_message_chunk",
+                   "content": {"type": "text", "text": text}},
+    }}
+
+
+def on_sigusr1(_signum, _frame):
+    global ticks
+    ticks += 1
+    send(chunk(f"tick {ticks}"))
+    log(f"emit tick {ticks}")
+
+
+signal.signal(signal.SIGUSR1, on_sigusr1)
+
+log(f"start pid={os.getpid()} cwd={os.getcwd()}")
+echo = os.environ.get("FAKE_ACP_ECHO_ENV")
+if echo:
+    log(f"env {echo}={os.environ.get(echo, '')}")
+
+for raw in sys.stdin:
+    raw = raw.strip()
+    if not raw:
+        continue
+    msg = json.loads(raw)
+    method = msg.get("method")
+    if method is None:
+        # A response to something we sent; nothing to do.
+        if msg.get("id") == pending_permission_id:
+            log("permission response " + json.dumps(msg.get("result"), sort_keys=True))
+            send({"jsonrpc": "2.0", "id": pending_prompt_id,
+                  "result": {"stopReason": "end_turn"}})
+            pending_prompt_id = None
+            pending_permission_id = None
+        continue
+    log(f"recv {method}")
+    rid = msg.get("id")
+    params = msg.get("params") or {}
+
+    if method == "initialize":
+        log("caps " + json.dumps(params.get("clientCapabilities", {}), sort_keys=True))
+        if os.environ.get("FAKE_ACP_INIT_FAIL") == "1":
+            send({"jsonrpc": "2.0", "id": rid,
+                  "error": {"code": -32000, "message": "fake init failure"}})
+            continue
+        send({"jsonrpc": "2.0", "id": rid, "result": {
+            "protocolVersion": params.get("protocolVersion", 1),
+            "agentCapabilities": {
+                "loadSession": os.environ.get("FAKE_ACP_NO_LOAD") != "1"},
+            "agentInfo": {"name": "fake-acp-agent", "version": "0.0.0"},
+            "authMethods": [],
+        }})
+    elif method == "session/new":
+        time.sleep(int(os.environ.get("FAKE_ACP_DELAY_SESSION_NEW_MS", "0")) / 1000)
+        send({"jsonrpc": "2.0", "id": rid, "result": {"sessionId": session_id}})
+        send(chunk("hello from fake"))
+        if os.environ.get("FAKE_ACP_EXIT_AFTER_NEW") == "1":
+            sys.exit(0)
+    elif method == "session/load":
+        session_id = params.get("sessionId")
+        log(f"recv session/load sessionId={session_id}")
+        if os.environ.get("FAKE_ACP_LOAD_FAIL") == "1":
+            send({"jsonrpc": "2.0", "id": rid,
+                  "error": {"code": -32000, "message": "fake load failure"}})
+            continue
+        for i in range(int(os.environ.get("FAKE_ACP_LOAD_REPLAY", "0"))):
+            send(chunk(f"replayed {i + 1}"))
+        send({"jsonrpc": "2.0", "id": rid, "result": {}})
+        send(chunk("hello after load"))
+    elif method == "session/cancel":
+        if os.environ.get("FAKE_ACP_EMIT_ON_CANCEL") == "1":
+            send(chunk("final on cancel"))
+        if (os.environ.get("FAKE_ACP_CANCEL_SETTLES") == "1"
+                and pending_prompt_id is not None):
+            send({"jsonrpc": "2.0", "id": pending_prompt_id,
+                  "result": {"stopReason": "cancelled"}})
+            pending_prompt_id = None
+            pending_permission_id = None
+        if os.environ.get("FAKE_ACP_EXIT_ON_CANCEL") == "1":
+            sys.exit(0)
+    elif method == "session/prompt":
+        if os.environ.get("FAKE_ACP_PERMISSION_AFTER_CANCEL") == "1":
+            if pending_prompt_id is None:
+                pending_prompt_id = rid
+                delayed_permission = True
+                continue
+            if delayed_permission:
+                delayed_permission = False
+                pending_permission_id = "permission-1"
+                send({"jsonrpc": "2.0", "id": pending_permission_id,
+                      "method": "session/request_permission", "params": {
+                          "sessionId": session_id,
+                          "toolCall": {"toolCallId": "tool-1", "fields": {}},
+                          "options": [
+                              {"optionId": "once", "name": "Allow once", "kind": "allow_once"},
+                              {"optionId": "deny", "name": "Deny", "kind": "reject_once"}
+                          ]
+                      }})
+                continue
+        if os.environ.get("FAKE_ACP_REQUEST_PERMISSION") == "1":
+            pending_prompt_id = rid
+            pending_permission_id = "permission-1"
+            send({"jsonrpc": "2.0", "id": pending_permission_id,
+                  "method": "session/request_permission", "params": {
+                      "sessionId": session_id,
+                      "toolCall": {"toolCallId": "tool-1", "fields": {}},
+                      "options": [
+                          {"optionId": "once", "name": "Allow once", "kind": "allow_once"},
+                          {"optionId": "session", "name": "Allow session", "kind": "allow_always"},
+                          {"optionId": "deny", "name": "Deny", "kind": "reject_once"}
+                      ]
+                  }})
+            continue
+        time.sleep(int(os.environ.get("FAKE_ACP_DELAY_PROMPT_MS", "0")) / 1000)
+        fail_once = os.environ.get("FAKE_ACP_PROMPT_FAIL_ONCE") == "1"
+        if os.environ.get("FAKE_ACP_PROMPT_FAIL") == "1" or (fail_once and prompt_failures == 0):
+            prompt_failures += 1
+            send({"jsonrpc": "2.0", "id": rid,
+                  "error": {"code": -32000, "message": "fake prompt failure"}})
+        else:
+            send({"jsonrpc": "2.0", "id": rid,
+                  "result": {"stopReason": "end_turn"}})
+    elif rid is not None:
+        send({"jsonrpc": "2.0", "id": rid,
+              "error": {"code": -32601, "message": f"method not found: {method}"}})
+
+if os.environ.get("FAKE_ACP_IGNORE_EOF") == "1":
+    while True:
+        signal.pause()

crates/maestro-acp/tests/spawn.rs

@@ -0,0 +1,394 @@
+//! `maestro-acp` against the fake adapter in `tests/fake_acp_agent.py`, plus
+//! one ignored test against the real `claude-code-acp`.
+
+use std::collections::HashMap;
+use std::path::{Path, PathBuf};
+use std::time::{Duration, Instant};
+
+use maestro_acp::schema::{ContentBlock, SessionUpdate};
+use maestro_acp::{AcpError, SpawnConfig, ADAPTER_BIN, INSTALL_COMMAND};
+use tempfile::TempDir;
+
+fn fake_agent() -> PathBuf {
+    Path::new(env!("CARGO_MANIFEST_DIR")).join("tests/fake_acp_agent.py")
+}
+
+/// A temp `bin/` holding the fake agent under the adapter's name, plus a
+/// log file the agent appends to. `PATH` for the spawn is just that dir.
+struct Fake {
+    dir: TempDir,
+}
+
+impl Fake {
+    fn new() -> Self {
+        let dir = TempDir::new().unwrap();
+        let bin = dir.path().join("bin");
+        std::fs::create_dir_all(&bin).unwrap();
+        std::fs::copy(fake_agent(), bin.join(ADAPTER_BIN)).unwrap();
+        Self { dir }
+    }
+
+    fn log_path(&self) -> PathBuf {
+        self.dir.path().join("agent.log")
+    }
+
+    fn log(&self) -> String {
+        std::fs::read_to_string(self.log_path()).unwrap_or_default()
+    }
+
+    /// The fake's `bin/` first, so it shadows any real adapter, then the
+    /// process `PATH` so the script's `python3` still resolves.
+    fn env(&self) -> HashMap<String, String> {
+        let path = format!(
+            "{}:{}",
+            self.dir.path().join("bin").display(),
+            std::env::var("PATH").unwrap_or_default()
+        );
+        HashMap::from([
+            ("PATH".to_string(), path),
+            (
+                "FAKE_ACP_LOG".to_string(),
+                self.log_path().to_string_lossy().into_owned(),
+            ),
+        ])
+    }
+
+    fn config(&self, cwd: &Path) -> SpawnConfig {
+        let mut config = SpawnConfig::new(cwd, self.env());
+        config.handshake_timeout = Duration::from_secs(10);
+        config
+    }
+
+    async fn wait_for_log(&self, needle: &str) {
+        let deadline = Instant::now() + Duration::from_secs(5);
+        while Instant::now() < deadline {
+            if self.log().contains(needle) {
+                return;
+            }
+            tokio::time::sleep(Duration::from_millis(20)).await;
+        }
+        panic!("log never contained {needle:?}:\n{}", self.log());
+    }
+
+    fn pid(&self) -> u32 {
+        self.log()
+            .lines()
+            .find_map(|line| line.strip_prefix("start pid="))
+            .and_then(|rest| rest.split(' ').next())
+            .and_then(|pid| pid.parse().ok())
+            .expect("pid in log")
+    }
+
+    async fn wait_for_exit(&self) {
+        let pid = self.pid();
+        let deadline = Instant::now() + Duration::from_secs(5);
+        while pid_alive(pid) && Instant::now() < deadline {
+            tokio::time::sleep(Duration::from_millis(20)).await;
+        }
+        assert!(!pid_alive(pid), "child {pid} still alive");
+    }
+}
+
+fn pid_alive(pid: u32) -> bool {
+    Path::new(&format!("/proc/{pid}")).exists()
+        && std::fs::read_to_string(format!("/proc/{pid}/stat"))
+            .map(|s| !s.contains(") Z "))
+            .unwrap_or(false)
+}
+
+#[tokio::test]
+async fn spawn_runs_adapter_in_cwd_with_env_and_restrictive_caps() {
+    let fake = Fake::new();
+    let cwd = TempDir::new().unwrap();
+    let mut config = fake.config(cwd.path());
+    config
+        .env
+        .insert("FAKE_ACP_ECHO_ENV".into(), "MAESTRO_SESSION_ID".into());
+    config
+        .env
+        .insert("MAESTRO_SESSION_ID".into(), "sess-123".into());
+
+    let session = maestro_acp::spawn(config).await.expect("spawn");
+    assert!(session.session_id().starts_with("fake-"));
+    assert!(pid_alive(session.pid()));
+
+    let log = fake.log();
+    let cwd_canon = cwd.path().canonicalize().unwrap();
+    assert!(
+        log.contains(&format!("cwd={}", cwd_canon.display())),
+        "child cwd missing from log:\n{log}"
+    );
+    assert!(log.contains("env MAESTRO_SESSION_ID=sess-123"), "{log}");
+    assert!(log.contains("recv initialize"), "{log}");
+    assert!(log.contains("recv session/new"), "{log}");
+    let caps = log
+        .lines()
+        .find_map(|l| l.strip_prefix("caps "))
+        .expect("caps line");
+    let caps: serde_json::Value = serde_json::from_str(caps).unwrap();
+    assert_eq!(caps["fs"]["readTextFile"], false);
+    assert_eq!(caps["fs"]["writeTextFile"], false);
+    assert_eq!(caps["terminal"], false);
+
+    session
+        .terminate(Duration::from_millis(100), Duration::from_secs(2))
+        .await;
+}
+
+#[tokio::test]
+async fn missing_adapter_names_the_install_command() {
+    let empty = TempDir::new().unwrap();
+    let cwd = TempDir::new().unwrap();
+    let env = HashMap::from([(
+        "PATH".to_string(),
+        empty.path().to_string_lossy().into_owned(),
+    )]);
+    let err = maestro_acp::spawn(SpawnConfig::new(cwd.path(), env))
+        .await
+        .expect_err("no adapter on PATH");
+    assert!(matches!(err, AcpError::AdapterMissing));
+    let msg = err.to_string();
+    assert!(msg.contains(ADAPTER_BIN), "{msg}");
+    assert!(msg.contains(INSTALL_COMMAND), "{msg}");
+}
+
+#[tokio::test]
+async fn session_updates_reach_the_taken_receiver() {
+    let fake = Fake::new();
+    let cwd = TempDir::new().unwrap();
+    let session = maestro_acp::spawn(fake.config(cwd.path()))
+        .await
+        .expect("spawn");
+
+    let mut updates = session.take_updates().expect("first take");
+    assert!(session.take_updates().is_none(), "handed out once");
+    let first = tokio::time::timeout(Duration::from_secs(5), updates.recv())
+        .await
+        .expect("update within 5s")
+        .expect("channel open");
+    assert_eq!(first.session_id.0.as_ref(), session.session_id());
+    match first.update {
+        SessionUpdate::AgentMessageChunk(chunk) => match chunk.content {
+            ContentBlock::Text(t) => assert_eq!(t.text, "hello from fake"),
+            other => panic!("unexpected content {other:?}"),
+        },
+        other => panic!("unexpected update {other:?}"),
+    }
+
+    session
+        .terminate(Duration::from_millis(100), Duration::from_secs(2))
+        .await;
+}
+
+#[tokio::test]
+async fn terminate_sends_cancel_then_sigterm() {
+    let fake = Fake::new();
+    let cwd = TempDir::new().unwrap();
+    let session = maestro_acp::spawn(fake.config(cwd.path()))
+        .await
+        .expect("spawn");
+    let pid = session.pid();
+
+    session
+        .terminate(Duration::from_millis(200), Duration::from_secs(2))
+        .await;
+    assert!(session.has_exited());
+    fake.wait_for_log("signal SIGTERM").await;
+
+    let log = fake.log();
+    let cancel = log.find("recv session/cancel").expect("cancel logged");
+    let term = log.find("signal SIGTERM").expect("SIGTERM logged");
+    assert!(cancel < term, "cancel must precede SIGTERM:\n{log}");
+    assert!(!pid_alive(pid), "child {pid} still alive");
+}
+
+#[tokio::test]
+async fn terminate_is_satisfied_by_an_exit_on_cancel() {
+    let fake = Fake::new();
+    let cwd = TempDir::new().unwrap();
+    let mut config = fake.config(cwd.path());
+    config
+        .env
+        .insert("FAKE_ACP_EXIT_ON_CANCEL".into(), "1".into());
+    let session = maestro_acp::spawn(config).await.expect("spawn");
+
+    session
+        .terminate(Duration::from_secs(2), Duration::from_secs(2))
+        .await;
+    assert!(session.has_exited());
+    let log = fake.log();
+    assert!(log.contains("recv session/cancel"), "{log}");
+    assert!(!log.contains("signal SIGTERM"), "cancel was enough:\n{log}");
+}
+
+#[tokio::test]
+async fn handshake_error_fails_the_spawn_and_reaps_the_child() {
+    let fake = Fake::new();
+    let cwd = TempDir::new().unwrap();
+    let mut config = fake.config(cwd.path());
+    config.env.insert("FAKE_ACP_INIT_FAIL".into(), "1".into());
+
+    let err = maestro_acp::spawn(config).await.expect_err("init fails");
+    assert!(matches!(err, AcpError::Handshake(_)), "{err}");
+    assert!(err.to_string().contains("fake init failure"), "{err}");
+    // Closing the connection gives the fake EOF on stdin; the SIGTERM that
+    // follows may find it already gone. Either way it must not survive.
+    let pid: u32 = fake
+        .log()
+        .lines()
+        .find_map(|l| l.strip_prefix("start pid="))
+        .and_then(|rest| rest.split(' ').next())
+        .and_then(|p| p.parse().ok())
+        .expect("pid in log");
+    let deadline = Instant::now() + Duration::from_secs(5);
+    while pid_alive(pid) && Instant::now() < deadline {
+        tokio::time::sleep(Duration::from_millis(20)).await;
+    }
+    assert!(!pid_alive(pid), "child {pid} outlived the failed spawn");
+}
+
+#[tokio::test]
+async fn early_exit_is_observed_after_a_successful_handshake() {
+    let fake = Fake::new();
+    let cwd = TempDir::new().unwrap();
+    let mut config = fake.config(cwd.path());
+    config
+        .env
+        .insert("FAKE_ACP_EXIT_AFTER_NEW".into(), "1".into());
+    let session = maestro_acp::spawn(config).await.expect("spawn");
+
+    let status = tokio::time::timeout(Duration::from_secs(5), session.wait())
+        .await
+        .expect("exit within 5s")
+        .expect("status");
+    assert!(status.success(), "{status}");
+    assert!(session.has_exited());
+}
+
+#[tokio::test]
+async fn child_exit_before_handshake_reports_exited_early() {
+    // A "adapter" that dies before answering anything.
+    let dir = TempDir::new().unwrap();
+    let bin = dir.path().join("bin");
+    std::fs::create_dir_all(&bin).unwrap();
+    let script = bin.join(ADAPTER_BIN);
+    std::fs::write(&script, "#!/bin/sh\necho 'not logged in' >&2\nexit 3\n").unwrap();
+    {
+        use std::os::unix::fs::PermissionsExt;
+        std::fs::set_permissions(&script, std::fs::Permissions::from_mode(0o755)).unwrap();
+    }
+    let cwd = TempDir::new().unwrap();
+    let env = HashMap::from([("PATH".to_string(), bin.to_string_lossy().into_owned())]);
+    let mut config = SpawnConfig::new(cwd.path(), env);
+    config.handshake_timeout = Duration::from_secs(10);
+
+    let err = maestro_acp::spawn(config).await.expect_err("child died");
+    match &err {
+        AcpError::ExitedEarly { status, stderr } => {
+            assert!(status.contains('3'), "{status}");
+            assert!(stderr.contains("not logged in"), "{stderr}");
+        }
+        other => panic!("unexpected {other:?}"),
+    }
+}
+
+#[tokio::test]
+async fn drop_terminates_and_reaps_the_child() {
+    let fake = Fake::new();
+    let cwd = TempDir::new().unwrap();
+    let mut config = fake.config(cwd.path());
+    config.env.insert("FAKE_ACP_IGNORE_EOF".into(), "1".into());
+    let session = maestro_acp::spawn(config).await.expect("spawn");
+
+    drop(session);
+
+    fake.wait_for_log("signal SIGTERM").await;
+    fake.wait_for_exit().await;
+}
+
+fn chunk_text(n: &maestro_acp::schema::SessionNotification) -> String {
+    match &n.update {
+        SessionUpdate::AgentMessageChunk(chunk) => match &chunk.content {
+            ContentBlock::Text(t) => t.text.clone(),
+            other => panic!("unexpected content {other:?}"),
+        },
+        other => panic!("unexpected update {other:?}"),
+    }
+}
+
+#[tokio::test]
+async fn load_session_resumes_the_stored_id_and_drops_the_replay() {
+    let fake = Fake::new();
+    let cwd = TempDir::new().unwrap();
+    let mut config = fake.config(cwd.path()).load_session("fake-old");
+    config.env.insert("FAKE_ACP_LOAD_REPLAY".into(), "3".into());
+
+    let session = maestro_acp::spawn(config).await.expect("spawn");
+    assert_eq!(session.session_id(), "fake-old");
+    let log = fake.log();
+    assert!(
+        log.contains("recv session/load sessionId=fake-old"),
+        "{log}"
+    );
+    assert!(!log.contains("recv session/new"), "{log}");
+
+    // The three replayed chunks never reach the receiver: the event log
+    // already holds them. The first notification after the response does.
+    let mut updates = session.take_updates().expect("updates");
+    let first = tokio::time::timeout(Duration::from_secs(5), updates.recv())
+        .await
+        .expect("update within 5s")
+        .expect("channel open");
+    assert_eq!(chunk_text(&first), "hello after load");
+    // Nothing queued behind it either.
+    tokio::time::sleep(Duration::from_millis(100)).await;
+    assert!(updates.try_recv().is_err(), "replay leaked through");
+
+    session
+        .terminate(Duration::from_millis(100), Duration::from_secs(2))
+        .await;
+}
+
+#[tokio::test]
+async fn load_session_requires_the_load_capability() {
+    let fake = Fake::new();
+    let cwd = TempDir::new().unwrap();
+    let mut config = fake.config(cwd.path()).load_session("fake-old");
+    config.env.insert("FAKE_ACP_NO_LOAD".into(), "1".into());
+
+    let err = maestro_acp::spawn(config)
+        .await
+        .expect_err("no loadSession");
+    assert!(matches!(err, AcpError::Handshake(_)), "{err}");
+    assert!(err.to_string().contains("loadSession"), "{err}");
+    assert!(!fake.log().contains("recv session/load"), "{}", fake.log());
+}
+
+#[tokio::test]
+async fn load_session_error_fails_the_spawn() {
+    let fake = Fake::new();
+    let cwd = TempDir::new().unwrap();
+    let mut config = fake.config(cwd.path()).load_session("fake-old");
+    config.env.insert("FAKE_ACP_LOAD_FAIL".into(), "1".into());
+
+    let err = maestro_acp::spawn(config).await.expect_err("load fails");
+    assert!(matches!(err, AcpError::Handshake(_)), "{err}");
+    assert!(err.to_string().contains("fake load failure"), "{err}");
+}
+
+/// End to end against the installed `claude-code-acp`. Needs Claude auth,
+/// takes seconds, so it is opt-in: `cargo test -p maestro-acp -- --ignored`.
+#[tokio::test]
+#[ignore]
+async fn real_adapter_handshake() {
+    let cwd = TempDir::new().unwrap();
+    let session = maestro_acp::spawn(SpawnConfig::new(cwd.path(), HashMap::new()))
+        .await
+        .expect("real claude-code-acp handshake");
+    assert!(!session.session_id().is_empty());
+    assert!(pid_alive(session.pid()));
+    session
+        .terminate(maestro_acp::CANCEL_GRACE, maestro_acp::TERM_GRACE)
+        .await;
+    assert!(session.has_exited());
+}

crates/maestro-cli/src/attach.rs

@@ -19,6 +19,12 @@ use tokio_tungstenite::tungstenite::Message;
 pub enum AttachError {
     #[error("ws: {0}")]
     WebSocket(#[from] tokio_tungstenite::tungstenite::Error),
+    #[error("daemon returned {status} ({code}): {message}")]
+    Rejected {
+        status: String,
+        code: String,
+        message: String,
+    },
     #[error("io: {0}")]
     Io(#[from] io::Error),
     #[error("termios: {0}")]
@@ -32,6 +38,21 @@ pub enum AttachError {
 }
 
 impl AttachError {
+    fn from_websocket(error: tokio_tungstenite::tungstenite::Error) -> Self {
+        if let tokio_tungstenite::tungstenite::Error::Http(response) = &error {
+            if let Some(body) = response.body().as_deref() {
+                if let Ok(error_body) = serde_json::from_slice::<maestro_protocol::ApiError>(body) {
+                    return Self::Rejected {
+                        status: response.status().to_string(),
+                        code: error_body.error.code,
+                        message: error_body.error.message,
+                    };
+                }
+            }
+        }
+        Self::WebSocket(error)
+    }
+
     /// True when the failure was an inability to reach the WS endpoint at the
     /// transport level (connection refused), as opposed to an HTTP-level
     /// rejection from a daemon that did answer.
@@ -111,7 +132,9 @@ fn current_winsize() -> Option<(u16, u16)> {
 /// byte that exits cleanly without killing the session.
 #[allow(clippy::result_large_err)]
 pub async fn run_attach_url(url: &str, detach_byte: u8) -> Result<(), AttachError> {
-    let (ws, _resp) = tokio_tungstenite::connect_async(url).await?;
+    let (ws, _resp) = tokio_tungstenite::connect_async(url)
+        .await
+        .map_err(AttachError::from_websocket)?;
     let (mut sink, mut stream) = ws.split();
 
     let raw = RawTty::enable()?;
@@ -233,4 +256,25 @@ mod tests {
             Err(AttachError::InvalidDetachKey(_))
         ));
     }
+
+    #[test]
+    fn attach_surfaces_structured_handshake_errors() {
+        let body = serde_json::to_vec(&maestro_protocol::ApiError::new(
+            "not_terminal",
+            "session is not a terminal session",
+        ))
+        .unwrap();
+        let response = tokio_tungstenite::tungstenite::http::Response::builder()
+            .status(409)
+            .body(Some(body))
+            .unwrap();
+
+        let error =
+            AttachError::from_websocket(tokio_tungstenite::tungstenite::Error::Http(response));
+
+        assert_eq!(
+            error.to_string(),
+            "daemon returned 409 Conflict (not_terminal): session is not a terminal session"
+        );
+    }
 }

crates/maestro-cli/src/dispatch.rs

@@ -96,20 +96,32 @@ pub async fn dispatch(
 }
 
 /// `maestro hooks install` (#106): write the shipped hook script under the
-/// user's data dir and register it in their Claude Code settings. Idempotent
-/// and foreign-hook-preserving — the guarantees live in [`maestro_hooks`].
+/// user's data dir and register it in every agent's hook file. Idempotent and
+/// foreign-hook-preserving — the guarantees live in [`maestro_hooks`]. One
+/// agent failing is reported and does not stop the others.
 #[allow(clippy::result_large_err)]
 fn run_hooks_install() -> Result<(), CliError> {
     let home = dirs::home_dir().ok_or(CliError::NoHome)?;
-    let changed = maestro_hooks::install_for_home(&home)?;
-    if changed {
-        println!(
-            "installed claude-code activity hook: {} → {}",
-            maestro_hooks::script_path(&home).display(),
-            maestro_hooks::settings_path(&home).display()
-        );
-    } else {
-        println!("claude-code activity hook already up to date");
+    let script = maestro_hooks::script_path(&home);
+    for (target, result) in maestro_hooks::install_for_home(&home) {
+        let agent = target.label();
+        let settings = target.settings_path(&home);
+        match result {
+            Ok(true) => {
+                println!(
+                    "installed {agent} activity hook: {} → {}",
+                    script.display(),
+                    settings.display()
+                );
+                if target == maestro_hooks::Target::Codex {
+                    // Codex will not run a hook it has not been told to
+                    // trust, and that approval is the operator's to give.
+                    println!("  codex will ask you to trust this hook the next time it starts");
+                }
+            }
+            Ok(false) => println!("{agent} activity hook already up to date"),
+            Err(e) => eprintln!("{agent} activity hook not installed: {e}"),
+        }
     }
     Ok(())
 }

crates/maestro-cli/src/sessions.rs

@@ -6,7 +6,7 @@ use std::io::Write;
 use maestro_protocol::display::abbreviate_dir;
 use maestro_protocol::{
     ActivityState, ClientError, CreateSessionRequest, DaemonClient, DaemonInfo, SendInputRequest,
-    Session, SessionStatus, WorktreeSpec,
+    Session, SessionStatus, SessionView, WorktreeSpec,
 };
 use serde_json::Value;
 
@@ -51,6 +51,7 @@ pub async fn run_spawn(client: &DaemonClient, args: SpawnArgs) -> Result<Session
     };
 
     let body = CreateSessionRequest {
+        view: Default::default(),
         cwd: args.cwd.clone(),
         command: args.command.clone(),
         env,
@@ -178,8 +179,8 @@ fn print_session_table(out: &mut impl Write, sessions: &[Session], info: &Daemon
     }
     writeln!(
         out,
-        "  {:<36}  {:<8}  {:<9}  {:<28}  {:<40}  {}",
-        "ID", "STATUS", "ACTIVITY", "DIR", "COMMAND", "BLOCKED"
+        "  {:<36}  {:<8}  {:<10}  {:<9}  {:<28}  {:<40}  {}",
+        "ID", "STATUS", "VIEW", "ACTIVITY", "DIR", "COMMAND", "BLOCKED"
     )
     .ok();
     for s in sorted {
@@ -189,6 +190,10 @@ fn print_session_table(out: &mut impl Write, sessions: &[Session], info: &Daemon
             SessionStatus::Running => "running",
             SessionStatus::Dead => "dead",
         };
+        let view = match s.view {
+            SessionView::Terminal => "terminal",
+            SessionView::Structured => "structured",
+        };
         let activity = match s.activity {
             ActivityState::Active => "active",
             ActivityState::Idle => "idle",
@@ -206,8 +211,8 @@ fn print_session_table(out: &mut impl Write, sessions: &[Session], info: &Daemon
         let blocked = blocked_label(s);
         writeln!(
             out,
-            "  {:<36}  {:<8}  {:<9}  {:<28}  {:<40}  {blocked}",
-            s.id, status, activity, dir, command
+            "  {:<36}  {:<8}  {:<10}  {:<9}  {:<28}  {:<40}  {blocked}",
+            s.id, status, view, activity, dir, command
         )
         .ok();
     }
@@ -229,13 +234,14 @@ mod tests {
     use std::path::PathBuf;
 
     use chrono::{TimeZone, Utc};
-    use maestro_protocol::{ActivityState, Session, SessionStatus};
+    use maestro_protocol::{ActivityState, Session, SessionStatus, SessionView};
     use uuid::Uuid;
 
     use super::DaemonInfo;
 
     fn session(cwd: &str, command: &str, id: u128) -> Session {
         Session {
+            view: Default::default(),
             id: Uuid::from_u128(id),
             cwd: PathBuf::from(cwd),
             command: command.into(),
@@ -251,6 +257,8 @@ mod tests {
             activity_since: chrono::Utc::now(),
             current_cwd: None,
             blocked_work: None,
+            last_focused_at: None,
+            acp_session_id: None,
         }
     }
 
@@ -282,6 +290,22 @@ mod tests {
         assert!(s.contains("idle"), "{s}");
     }
 
+    #[test]
+    fn table_exposes_terminal_and_structured_views() {
+        let terminal = session("/tmp", "bash", 1);
+        let mut structured = session("/tmp", "claude", 2);
+        structured.view = SessionView::Structured;
+
+        let mut buf = Vec::new();
+        super::print_session_table(&mut buf, &[terminal, structured], &info(""));
+        let out = String::from_utf8(buf).unwrap();
+        let lines: Vec<&str> = out.lines().collect();
+        let header = lines.iter().position(|line| line.contains("VIEW")).unwrap();
+
+        assert!(lines[header + 1].contains("terminal"), "{out}");
+        assert!(lines[header + 2].contains("structured"), "{out}");
+    }
+
     #[test]
     fn live_cwd_overrides_spawn_dir_in_table() {
         let mut s = session("/home/naps/maestro", "bash", 1);

crates/maestro-cli/tests/against_mock_daemon.rs

@@ -91,6 +91,7 @@ async fn spawn_round_trips_through_the_daemon() {
     let created = mock
         .client()
         .create_session(&maestro_protocol::CreateSessionRequest {
+            view: Default::default(),
             cwd: "/home/mock".into(),
             command: "bash".into(),
             env: Default::default(),

crates/maestro-config/src/lib.rs

@@ -30,6 +30,11 @@ pub const FILE_NAME: &str = "config.toml";
 /// Last-resort daemon HTTP base, matching the daemon's own default `bind_addr`.
 pub const DEFAULT_DAEMON_URL: &str = "http://127.0.0.1:7070";
 
+/// Leader key both clients use when `[tui].leader` is unset (#159). Canonical
+/// key form, the spelling `InputKey::parse` and the web's `canonicalizeKey`
+/// both produce.
+pub const DEFAULT_LEADER: &str = "ctrl-a";
+
 #[derive(Debug, thiserror::Error)]
 pub enum ConfigError {
     #[error("io: {0}")]
@@ -152,6 +157,15 @@ pub struct TuiSection {
     pub keymap_insert: BTreeMap<String, String>,
 }
 
+impl TuiSection {
+    /// The configured leader, or [`DEFAULT_LEADER`]. Named `[tui].leader` for
+    /// history, but read by every client: the daemon serves it on
+    /// `GET /api/info` so the web follows the same knob (#159).
+    pub fn leader(&self) -> &str {
+        self.leader.as_deref().unwrap_or(DEFAULT_LEADER)
+    }
+}
+
 /// Palette presets supported by the TUI's `[tui].theme` setting.
 #[derive(Debug, Clone, Copy, PartialEq, Eq)]
 pub enum TuiTheme {

crates/maestro-daemon/Cargo.toml

@@ -28,6 +28,7 @@ dirs.workspace = true
 futures-util.workspace = true
 include_dir = { workspace = true, optional = true }
 libc.workspace = true
+maestro-acp.workspace = true
 mime_guess = { workspace = true, optional = true }
 maestro-config.workspace = true
 maestro-hooks = { workspace = true, default-features = false }
@@ -42,6 +43,7 @@ tracing-subscriber.workspace = true
 uuid.workspace = true
 
 [dev-dependencies]
+libc.workspace = true
 reqwest.workspace = true
 tokio-tungstenite.workspace = true
 urlencoding = "2"

crates/maestro-daemon/src/activity.rs

@@ -66,6 +66,23 @@ pub fn decide(idle_for: Duration, awaiting_input: bool) -> ActivityState {
     }
 }
 
+/// Derive a structured session's sidebar state from its ACP projection.
+pub fn decide_structured(
+    turn_active: bool,
+    pending_approval: bool,
+    turn_failed: bool,
+) -> ActivityState {
+    if turn_failed {
+        ActivityState::Error
+    } else if pending_approval {
+        ActivityState::AwaitingInput
+    } else if turn_active {
+        ActivityState::Active
+    } else {
+        ActivityState::Idle
+    }
+}
+
 /// How long a session's pane must be continuously focused (a client's pane,
 /// not a sidebar highlight) before an `AwaitingInput` glow clears: the
 /// operator has looked, so the rail stops asking for attention.
@@ -136,6 +153,17 @@ mod tests {
         );
     }
 
+    #[test]
+    fn structured_activity_follows_lifecycle_with_approval_precedence() {
+        assert_eq!(decide_structured(false, false, false), ActivityState::Idle);
+        assert_eq!(decide_structured(true, false, false), ActivityState::Active);
+        assert_eq!(
+            decide_structured(true, true, false),
+            ActivityState::AwaitingInput
+        );
+        assert_eq!(decide_structured(false, false, true), ActivityState::Error);
+    }
+
     #[test]
     fn report_is_in_force_until_exactly_its_expiry() {
         let ttl = Duration::from_secs(300);

crates/maestro-daemon/src/attach.rs

@@ -26,11 +26,17 @@ pub(crate) async fn serve(
 ) -> Result<(), axum::Error> {
     let (mut sink, mut stream) = socket.split();
 
+    // This client's claim on the shared window size. Registered up front and
+    // released on every exit below, so a socket that dies mid-session stops
+    // constraining the size for the clients still attached.
+    let viewport = manager.attach_viewport();
+
     // NAP-229: send buffered scrollback up-front so the client sees the last
     // screenful immediately instead of a blank terminal. The replay lock the
     // bridge held during snapshot+subscribe guarantees no byte appears both
     // here and on the live receiver, and none is dropped at the seam.
     if !replay.is_empty() && sink.send(Message::Binary(replay)).await.is_err() {
+        manager.release_viewport(id, viewport).await;
         return Ok(());
     }
 
@@ -70,7 +76,7 @@ pub(crate) async fn serve(
                     if let Ok(ctrl) = serde_json::from_str::<ClientControl>(&text) {
                         match ctrl {
                             ClientControl::Resize { cols, rows } => {
-                                let _ = manager.resize(id, cols, rows).await;
+                                let _ = manager.set_viewport(id, viewport, cols, rows).await;
                             }
                             ClientControl::Ping => {
                                 let pong = serde_json::to_string(&ClientControl::Pong)
@@ -88,6 +94,8 @@ pub(crate) async fn serve(
         }
     }
 
+    manager.release_viewport(id, viewport).await;
+
     if session_ended {
         let _ = sink.send(Message::Close(None)).await;
     }

crates/maestro-daemon/src/cli.rs

@@ -51,17 +51,23 @@ async fn run(config_override: Option<PathBuf>) -> Result<(), Box<dyn Error>> {
     // First-start hook auto-install (#106). Best-effort, before serving: a
     // session spawned right away should already carry the hook.
     if config.hooks_auto_install {
-        match crate::hooks::auto_install(&config.home_dir) {
-            crate::hooks::AutoInstallOutcome::Installed => {
-                tracing::info!("installed claude-code activity hook (#106)");
+        for (target, outcome) in crate::hooks::auto_install(&config.home_dir) {
+            let agent = target.label();
+            match outcome {
+                crate::hooks::AutoInstallOutcome::Installed => {
+                    tracing::info!(agent, "installed activity hook (#106)");
+                }
+                crate::hooks::AutoInstallOutcome::Upgraded => {
+                    tracing::info!(agent, "updated activity hook to this build (#106)");
+                }
+                crate::hooks::AutoInstallOutcome::Failed => {
+                    tracing::warn!(
+                        agent,
+                        "hooks auto-install failed; run `maestro hooks install` manually"
+                    );
+                }
+                _ => {}
             }
-            crate::hooks::AutoInstallOutcome::Upgraded => {
-                tracing::info!("updated claude-code activity hook to this build (#106)");
-            }
-            crate::hooks::AutoInstallOutcome::Failed => {
-                tracing::warn!("hooks auto-install failed; run `maestro hooks install` manually");
-            }
-            _ => {}
         }
     }
     // No worktree dir to pre-create: without an override the worktrees live
@@ -100,20 +106,34 @@ async fn run(config_override: Option<PathBuf>) -> Result<(), Box<dyn Error>> {
     projects.start_background_refresh();
 
     let router = local_api::router(local_api::state_for(
-        manager,
+        manager.clone(),
         config.hostname.clone(),
         config.home_dir.clone(),
         config.spawn_presets.clone(),
         projects,
+        config.leader.clone(),
     ));
 
     let listener = TcpListener::bind(config.bind_addr).await?;
     let bound = listener.local_addr()?;
     tracing::info!(addr = %bound, "API listening");
 
-    let shutdown = async {
-        let _ = tokio::signal::ctrl_c().await;
-        tracing::info!("ctrl-c received — shutting down");
+    // Ctrl-C at a terminal or SIGTERM from systemd: either one is a
+    // shutdown, and both must reach the adapter children below (#134). The
+    // unit's `KillMode=process` signals only the daemon, so nothing else
+    // would end them.
+    let shutdown_manager = manager.clone();
+    let shutdown = async move {
+        let mut sigterm = tokio::signal::unix::signal(tokio::signal::unix::SignalKind::terminate())
+            .expect("install SIGTERM handler");
+        tokio::select! {
+            _ = tokio::signal::ctrl_c() => tracing::info!("ctrl-c received — shutting down"),
+            _ = sigterm.recv() => tracing::info!("SIGTERM received — shutting down"),
+        }
+        // Axum waits for upgraded WebSockets to drain. Structured children
+        // must be settled before that wait, while the signal path still owns
+        // the shutdown order (#179).
+        shutdown_manager.shutdown().await;
     };
 
     axum::serve(listener, router)

crates/maestro-daemon/src/config.rs

@@ -92,6 +92,11 @@ pub struct DaemonConfig {
     /// start when none is present (#106): `[hooks].auto_install`, default
     /// `true`.
     pub hooks_auto_install: bool,
+    /// Canonical leader key advertised to clients in `GET /api/info` (#159):
+    /// `[tui].leader`, default [`maestro_config::DEFAULT_LEADER`]. The daemon
+    /// never binds it itself; it serves it so the web client and the TUI read
+    /// one knob.
+    pub leader: String,
 }
 
 impl DaemonConfig {
@@ -197,6 +202,7 @@ pub fn load_config(path: &Path, env: EnvOverrides) -> Result<DaemonConfig, Confi
         project_roots,
         project_scan_depth,
         hooks_auto_install: file.hooks.auto_install(),
+        leader: file.tui.leader().to_string(),
     })
 }
 
@@ -233,6 +239,29 @@ pub fn system_hostname() -> String {
 mod tests {
     use super::*;
 
+    /// #159: the leader the operator set for the TUI is what the daemon
+    /// advertises, so rebinding it once moves both clients' chord.
+    #[test]
+    fn leader_defaults_to_ctrl_a_and_follows_the_tui_section() {
+        let dir = tempfile::tempdir().unwrap();
+        let path = dir.path().join("config.toml");
+
+        std::fs::write(&path, "").unwrap();
+        let cfg = load_config(&path, EnvOverrides::default()).unwrap();
+        assert_eq!(cfg.leader, "ctrl-a");
+
+        std::fs::write(
+            &path,
+            r#"
+[tui]
+leader = "ctrl-b"
+"#,
+        )
+        .unwrap();
+        let cfg = load_config(&path, EnvOverrides::default()).unwrap();
+        assert_eq!(cfg.leader, "ctrl-b");
+    }
+
     #[test]
     fn hooks_auto_install_defaults_true_and_is_opt_out() {
         let dir = tempfile::tempdir().unwrap();

crates/maestro-daemon/src/hooks.rs

@@ -1,37 +1,53 @@
 //! First-start hook auto-install (#106).
 //!
-//! The daemon runs [`auto_install`] once at startup: unless the user's
-//! `~/.claude/settings.json` already carries exactly what this build ships
-//! (and `[hooks].auto_install` hasn't opted out — checked by the caller), the
-//! same installer `maestro hooks install` uses writes it. That covers
-//! upgrades as well as first starts: an install from a maestro that had fewer
-//! events — #131 added `UserPromptSubmit` to a hook #106 had already put in
-//! everyone's settings — is rewritten rather than left half-wired. Best-effort:
-//! a failure is warned about and never blocks startup. The same global hook
-//! serves every Claude Code session on the machine, so nothing here targets
-//! repositories or worktrees.
+//! The daemon runs [`auto_install`] once at startup: for every agent maestro
+//! knows how to hook ([`maestro_hooks::Target`]), unless that agent's hook
+//! file already carries exactly what this build ships (and `[hooks]
+//! .auto_install` hasn't opted out — checked by the caller), the same
+//! installer `maestro hooks install` uses writes it. That covers upgrades as
+//! well as first starts: an install from a maestro that had fewer events —
+//! #131 added `UserPromptSubmit` to a hook #106 had already put in everyone's
+//! settings — is rewritten rather than left half-wired. Best-effort: a
+//! failure is warned about and never blocks startup, and one target failing
+//! does not stop the others. The same global hook serves every session on the
+//! machine, so nothing here targets repositories or worktrees.
 
 use std::path::Path;
 
-/// Install the Claude Code activity hook for `home_dir` unless the current
-/// one is already there or the home dir is unresolvable (`""`). Returns what
-/// happened; an older install being brought up to date is
-/// [`AutoInstallOutcome::Upgraded`], so the log can say so.
-pub fn auto_install(home_dir: &str) -> AutoInstallOutcome {
+use maestro_hooks::Target;
+
+/// Install the activity hook for every [`Target`] under `home_dir`, skipping
+/// any whose install is already current. Returns what happened per target —
+/// an older install being brought up to date is
+/// [`AutoInstallOutcome::Upgraded`], so the log can say so. An unresolvable
+/// home dir (`""`) reports every target as [`AutoInstallOutcome::Skipped`].
+pub fn auto_install(home_dir: &str) -> Vec<(Target, AutoInstallOutcome)> {
+    Target::ALL
+        .iter()
+        .map(|&target| (target, auto_install_target(target, home_dir)))
+        .collect()
+}
+
+fn auto_install_target(target: Target, home_dir: &str) -> AutoInstallOutcome {
     if home_dir.is_empty() {
         return AutoInstallOutcome::Skipped;
     }
-    let settings = maestro_hooks::settings_path(Path::new(home_dir));
-    let script = maestro_hooks::script_path(Path::new(home_dir));
-    if maestro_hooks::is_current(&settings, &script) {
+    let home = Path::new(home_dir);
+    let settings = target.settings_path(home);
+    let script = maestro_hooks::script_path(home);
+    if maestro_hooks::is_current(target, &settings, &script) {
         return AutoInstallOutcome::AlreadyPresent;
     }
     let stale = maestro_hooks::is_installed(&settings);
-    match maestro_hooks::install_for_home(Path::new(home_dir)) {
+    match maestro_hooks::install_target(target, home) {
         Ok(_) if stale => AutoInstallOutcome::Upgraded,
         Ok(_) => AutoInstallOutcome::Installed,
         Err(e) => {
-            tracing::warn!(error = %e, "hooks auto-install failed (non-fatal)");
+            tracing::warn!(
+                target = target.label(),
+                error = %e,
+                "hooks auto-install failed (non-fatal)"
+            );
             AutoInstallOutcome::Failed
         }
     }
@@ -52,15 +68,50 @@ pub enum AutoInstallOutcome {
 mod tests {
     use super::*;
 
+    /// The outcome recorded for one target.
+    fn outcome(outcomes: &[(Target, AutoInstallOutcome)], target: Target) -> AutoInstallOutcome {
+        outcomes
+            .iter()
+            .find(|(t, _)| *t == target)
+            .map(|(_, o)| *o)
+            .expect("every target is reported")
+    }
+
     /// Everything happens under a temp `$HOME`; the developer's own
-    /// `~/.claude/settings.json` is never read or written.
+    /// `~/.claude/settings.json` and `~/.codex/hooks.json` are never read or
+    /// written.
     #[test]
     fn installs_when_settings_carry_no_maestro_hook() {
         let dir = tempfile::tempdir().unwrap();
-        let outcome = auto_install(dir.path().to_str().unwrap());
-        assert_eq!(outcome, AutoInstallOutcome::Installed);
-        let settings = dir.path().join(".claude/settings.json");
-        assert!(maestro_hooks::is_installed(&settings));
+        let outcomes = auto_install(dir.path().to_str().unwrap());
+        for target in Target::ALL {
+            assert_eq!(
+                outcome(&outcomes, target),
+                AutoInstallOutcome::Installed,
+                "{}",
+                target.label()
+            );
+            assert!(maestro_hooks::is_installed(
+                &target.settings_path(dir.path())
+            ));
+        }
+    }
+
+    /// Every agent maestro knows about is hooked, not just Claude Code: a
+    /// codex session reports activity and its first prompt the same way.
+    #[test]
+    fn codex_gets_its_own_hook_file() {
+        let dir = tempfile::tempdir().unwrap();
+        auto_install(dir.path().to_str().unwrap());
+        let hooks = dir.path().join(".codex/hooks.json");
+        let root: serde_json::Value =
+            serde_json::from_str(&std::fs::read_to_string(&hooks).unwrap()).unwrap();
+        let events = root["hooks"].as_object().unwrap();
+        assert!(events.contains_key("PermissionRequest"));
+        assert!(
+            !events.contains_key("Notification"),
+            "codex has no Notification"
+        );
     }
 
     #[test]
@@ -69,14 +120,22 @@ mod tests {
         let home = dir.path().to_str().unwrap();
         auto_install(home);
         // A current install is left exactly as it is.
-        let settings = dir.path().join(".claude/settings.json");
-        let before = std::fs::read_to_string(&settings).unwrap();
-        assert_eq!(auto_install(home), AutoInstallOutcome::AlreadyPresent);
-        assert_eq!(
-            before,
-            std::fs::read_to_string(&settings).unwrap(),
-            "already-installed settings must not be rewritten"
-        );
+        let before: Vec<String> = Target::ALL
+            .iter()
+            .map(|t| std::fs::read_to_string(t.settings_path(dir.path())).unwrap())
+            .collect();
+        let outcomes = auto_install(home);
+        for (i, target) in Target::ALL.iter().enumerate() {
+            assert_eq!(
+                outcome(&outcomes, *target),
+                AutoInstallOutcome::AlreadyPresent
+            );
+            assert_eq!(
+                before[i],
+                std::fs::read_to_string(target.settings_path(dir.path())).unwrap(),
+                "already-installed settings must not be rewritten"
+            );
+        }
     }
 
     /// An install from an older maestro — present, but missing an event this
@@ -87,7 +146,7 @@ mod tests {
         let dir = tempfile::tempdir().unwrap();
         let home = dir.path().to_str().unwrap();
         auto_install(home);
-        let settings = dir.path().join(".claude/settings.json");
+        let settings = Target::ClaudeCode.settings_path(dir.path());
         let script = maestro_hooks::script_path(dir.path());
 
         let mut root: serde_json::Value =
@@ -96,12 +155,23 @@ mod tests {
         std::fs::write(&settings, serde_json::to_string_pretty(&root).unwrap()).unwrap();
         std::fs::write(&script, "#!/bin/sh\nexit 0\n").unwrap();
 
-        assert_eq!(auto_install(home), AutoInstallOutcome::Upgraded);
-        assert!(maestro_hooks::is_current(&settings, &script));
+        let outcomes = auto_install(home);
+        assert_eq!(
+            outcome(&outcomes, Target::ClaudeCode),
+            AutoInstallOutcome::Upgraded
+        );
+        assert!(maestro_hooks::is_current(
+            Target::ClaudeCode,
+            &settings,
+            &script
+        ));
     }
 
     #[test]
     fn unresolvable_home_is_skipped() {
-        assert_eq!(auto_install(""), AutoInstallOutcome::Skipped);
+        let outcomes = auto_install("");
+        for target in Target::ALL {
+            assert_eq!(outcome(&outcomes, target), AutoInstallOutcome::Skipped);
+        }
     }
 }

crates/maestro-daemon/src/lib.rs

@@ -21,6 +21,7 @@ pub mod hooks;
 pub mod local_api;
 pub mod panes;
 pub mod proc;
+pub mod projection;
 pub mod projects;
 pub mod pty;
 pub mod release;
@@ -30,6 +31,7 @@ pub mod spawn_history;
 #[cfg(feature = "web")]
 pub mod static_bundle;
 pub mod tmux;
+pub mod viewport;
 pub mod worktree;
 pub mod worktree_probe;
 

crates/maestro-daemon/src/local_api.rs

@@ -21,12 +21,13 @@ use maestro_config::SpawnPreset;
 use maestro_protocol::{
     routes, ApiError, CatalogEvent, CreateSessionRequest, DaemonInfo, GitRoot, NameBatch,
     RenameSessionRequest, ReportActivityRequest, SendInputRequest, Session, SetFocusRequest,
-    PROTOCOL_VERSION,
+    StructuredApprovalDecision, StructuredEvent, StructuredPromptRequest, PROTOCOL_VERSION,
 };
 use serde::Deserialize;
 use uuid::Uuid;
 
-use crate::session::SessionManager;
+use crate::session::{QueueAcpPrompt, SessionError, SessionManager};
+use crate::sidecar::EventCursor;
 
 #[derive(Debug, Clone)]
 pub struct LocalApiState {
@@ -39,6 +40,10 @@ pub struct LocalApiState {
     pub presets: Arc<Vec<SpawnPreset>>,
     /// Project discovery (#54) backing `GET /api/projects`.
     pub projects: Arc<crate::projects::ProjectScanner>,
+    /// Configured leader key (`[tui].leader`) advertised in `GET /api/info`
+    /// (#159), so the web client binds the chord the operator configured
+    /// rather than its own default.
+    pub leader: Arc<String>,
 }
 
 pub fn router(state: LocalApiState) -> Router {
@@ -60,7 +65,15 @@ pub fn router(state: LocalApiState) -> Router {
         .route(routes::NAMES, get(names))
         .route(routes::INFO, get(daemon_info))
         .route(routes::EVENTS, any(events_ws))
-        .route(routes::patterns::ATTACH, any(attach_ws));
+        .route(routes::patterns::ATTACH, any(attach_ws))
+        .route(routes::patterns::STRUCTURED, any(structured_ws))
+        .route(routes::patterns::STRUCTURED_REPLAY, get(structured_replay))
+        .route(routes::patterns::STRUCTURED_PROMPT, post(structured_prompt))
+        .route(routes::patterns::STRUCTURED_CANCEL, post(structured_cancel))
+        .route(
+            routes::patterns::STRUCTURED_APPROVAL,
+            post(structured_approval),
+        );
     #[cfg(feature = "haiku-autoname")]
     {
         router = router.route(routes::patterns::SESSION_PROMPT, post(session_prompt));
@@ -166,6 +179,8 @@ fn session_error_status(code: &str) -> StatusCode {
         // The session outlived its pane: nothing to type into, and nothing
         // the daemon can do about it.
         "not_running" => StatusCode::CONFLICT,
+        "not_terminal" => StatusCode::CONFLICT,
+        "shutting_down" => StatusCode::SERVICE_UNAVAILABLE,
         _ => StatusCode::BAD_GATEWAY,
     }
 }
@@ -219,6 +234,7 @@ async fn daemon_info(State(s): State<LocalApiState>) -> Json<DaemonInfo> {
         presets: (*s.presets).clone(),
         build: crate::release::build_info(),
         instance: crate::release::instance_id().to_string(),
+        leader: (*s.leader).clone(),
     })
 }
 
@@ -292,11 +308,10 @@ async fn rename_session(
     }
 }
 
-/// `POST /api/sessions/:id/activity` (#105): an agent reports its own state.
-/// The report holds above the daemon's inference for a TTL, then inference
-/// resumes — an agent that dies mid-run cannot pin its session at `Error`
-/// forever. Unknown session is 404; an unknown state value is rejected by the
-/// JSON decoder (422) rather than coerced. Answers `204 No Content`.
+/// `POST /api/sessions/:id/activity` (#105): an agent reports a terminal
+/// session's state. Structured sessions acknowledge and ignore these reports
+/// because their activity comes from ACP. Unknown session is 404; an unknown
+/// state value is rejected by the JSON decoder (422). Answers `204 No Content`.
 async fn report_activity(
     State(s): State<LocalApiState>,
     Path(id): Path<Uuid>,
@@ -363,6 +378,126 @@ fn error_response(status: StatusCode, code: &str, message: &str) -> Response {
     (status, Json(ApiError::new(code, message))).into_response()
 }
 
+#[derive(Debug, Deserialize)]
+struct ReplayQuery {
+    since: Option<u64>,
+    before: Option<u64>,
+    limit: Option<usize>,
+}
+
+const MAX_STRUCTURED_REPLAY_LIMIT: usize = 500;
+
+async fn structured_replay(
+    State(s): State<LocalApiState>,
+    Path(id): Path<Uuid>,
+    Query(query): Query<ReplayQuery>,
+) -> Response {
+    if query.since.is_some() && query.before.is_some() {
+        return error_response(
+            StatusCode::BAD_REQUEST,
+            "invalid_cursor",
+            "use either since or before, not both",
+        );
+    }
+    let cursor = match query.before {
+        Some(before) => EventCursor::Before(Some(before)),
+        None => EventCursor::Since(query.since.unwrap_or(0)),
+    };
+    match s
+        .manager
+        .read_acp_projection_replay(
+            id,
+            cursor,
+            query
+                .limit
+                .unwrap_or(100)
+                .clamp(1, MAX_STRUCTURED_REPLAY_LIMIT),
+        )
+        .await
+    {
+        Ok(Some(events)) => Json(events).into_response(),
+        // A terminal session, or a structured session whose adapter is no
+        // longer live, cannot provide a coherent replay continuation.
+        Ok(None) => error_response(
+            StatusCode::CONFLICT,
+            "not_structured",
+            "session is not a live structured session",
+        ),
+        Err(e) => {
+            let info = e.to_error_info();
+            error_response(session_error_status(&info.code), &info.code, &info.message)
+        }
+    }
+}
+
+async fn structured_prompt(
+    State(s): State<LocalApiState>,
+    Path(id): Path<Uuid>,
+    Json(body): Json<StructuredPromptRequest>,
+) -> Response {
+    match s.manager.queue_acp_prompt(id, body.prompt).await {
+        Ok(QueueAcpPrompt::Queued) => StatusCode::NO_CONTENT.into_response(),
+        Ok(QueueAcpPrompt::InFlight) => error_response(
+            StatusCode::CONFLICT,
+            "turn_in_flight",
+            "the structured session already has an active turn",
+        ),
+        Ok(QueueAcpPrompt::Unavailable) => error_response(
+            StatusCode::CONFLICT,
+            "not_structured",
+            "session is not a live structured session",
+        ),
+        Ok(QueueAcpPrompt::Failed(message)) => {
+            error_response(StatusCode::BAD_GATEWAY, "acp_prompt_failed", &message)
+        }
+        Err(e) => {
+            let info = e.to_error_info();
+            error_response(session_error_status(&info.code), &info.code, &info.message)
+        }
+    }
+}
+
+async fn structured_cancel(State(s): State<LocalApiState>, Path(id): Path<Uuid>) -> Response {
+    match s.manager.cancel_acp_turn(id).await {
+        Ok(true) => StatusCode::NO_CONTENT.into_response(),
+        Ok(false) => error_response(
+            StatusCode::CONFLICT,
+            "not_structured",
+            "session is not a live structured session",
+        ),
+        Err(e) => {
+            let info = e.to_error_info();
+            error_response(session_error_status(&info.code), &info.code, &info.message)
+        }
+    }
+}
+
+async fn structured_approval(
+    State(s): State<LocalApiState>,
+    Path((id, nonce)): Path<(Uuid, String)>,
+    Json(decision): Json<StructuredApprovalDecision>,
+) -> Response {
+    let decision = match decision {
+        StructuredApprovalDecision::AllowOnce => crate::session::ApprovalDecision::AllowOnce,
+        StructuredApprovalDecision::AllowForSession => {
+            crate::session::ApprovalDecision::AllowForSession
+        }
+        StructuredApprovalDecision::Deny => crate::session::ApprovalDecision::Deny,
+    };
+    match s.manager.resolve_acp_approval(id, &nonce, decision).await {
+        Ok(Some(())) => StatusCode::NO_CONTENT.into_response(),
+        Ok(None) => error_response(
+            StatusCode::CONFLICT,
+            "not_structured",
+            "session is not a live structured session",
+        ),
+        Err(e) => {
+            let info = e.to_error_info();
+            error_response(session_error_status(&info.code), &info.code, &info.message)
+        }
+    }
+}
+
 /// Convenience constructor — pulls the bits `LocalApiState` needs from
 /// `DaemonConfig` so callers don't have to assemble it by hand. The project
 /// scanner starts with its cache cold; wire
@@ -374,6 +509,7 @@ pub fn state_for(
     home_dir: impl Into<String>,
     presets: Vec<SpawnPreset>,
     projects: Arc<crate::projects::ProjectScanner>,
+    leader: impl Into<String>,
 ) -> LocalApiState {
     LocalApiState {
         manager,
@@ -381,6 +517,7 @@ pub fn state_for(
         home_dir: Arc::new(home_dir.into()),
         presets: Arc::new(presets),
         projects,
+        leader: Arc::new(leader.into()),
     }
 }
 
@@ -398,12 +535,23 @@ async fn attach_ws(
     State(s): State<LocalApiState>,
     ws: axum::extract::WebSocketUpgrade,
 ) -> Result<Response, Response> {
-    let Some((replay, rx)) = s.manager.subscribe_pty_with_replay(id).await else {
-        return Err(error_response(
-            StatusCode::NOT_FOUND,
-            "unknown_session",
-            "no such session on this daemon",
-        ));
+    let (replay, rx) = match s.manager.subscribe_pty_with_replay(id).await {
+        Ok(subscription) => subscription,
+        Err(SessionError::NotFound(_)) => {
+            return Err(error_response(
+                StatusCode::NOT_FOUND,
+                "unknown_session",
+                "no such session on this daemon",
+            ));
+        }
+        Err(error) => {
+            let info = error.to_error_info();
+            return Err(error_response(
+                session_error_status(&info.code),
+                &info.code,
+                &info.message,
+            ));
+        }
     };
     let manager = s.manager.clone();
     Ok(ws.on_upgrade(move |socket| async move {
@@ -411,6 +559,75 @@ async fn attach_ws(
     }))
 }
 
+#[allow(clippy::result_large_err)]
+async fn structured_ws(
+    Path(id): Path<Uuid>,
+    State(s): State<LocalApiState>,
+    ws: axum::extract::WebSocketUpgrade,
+) -> Result<Response, Response> {
+    let Some((snapshot, state, rx)) = s
+        .manager
+        .subscribe_acp_projection(id, EventCursor::Since(0))
+        .await
+        .map_err(|e| {
+            let info = e.to_error_info();
+            error_response(session_error_status(&info.code), &info.code, &info.message)
+        })?
+    else {
+        return Err(error_response(
+            StatusCode::CONFLICT,
+            "not_structured",
+            "session is not a live structured session",
+        ));
+    };
+    Ok(ws.on_upgrade(move |socket| async move {
+        let _ = pump_structured(socket, snapshot, state, rx).await;
+    }))
+}
+
+async fn pump_structured(
+    socket: axum::extract::ws::WebSocket,
+    snapshot: maestro_protocol::TranscriptSnapshot,
+    state: maestro_protocol::ReducedState,
+    mut rx: tokio::sync::broadcast::Receiver<crate::projection::ProjectionUpdate>,
+) -> Result<(), axum::Error> {
+    use axum::extract::ws::Message;
+    use futures_util::{SinkExt, StreamExt};
+
+    let (mut sink, mut stream) = socket.split();
+    for event in [
+        StructuredEvent::TranscriptSnapshot { snapshot },
+        StructuredEvent::ReducedState { state },
+    ] {
+        if sink
+            .send(Message::Text(
+                serde_json::to_string(&event).expect("structured event encode"),
+            ))
+            .await
+            .is_err()
+        {
+            return Ok(());
+        }
+    }
+    loop {
+        tokio::select! {
+            update = rx.recv() => match update {
+                Ok(update) => {
+                    let event = StructuredEvent::ProjectionUpdate { transcript: update.transcript, state: update.state };
+                    if sink.send(Message::Text(serde_json::to_string(&event).expect("structured event encode"))).await.is_err() { break; }
+                }
+                Err(tokio::sync::broadcast::error::RecvError::Lagged(_)) => break,
+                Err(tokio::sync::broadcast::error::RecvError::Closed) => break,
+            },
+            frame = stream.next() => match frame {
+                None | Some(Err(_)) | Some(Ok(Message::Close(_))) => break,
+                Some(Ok(_)) => {},
+            },
+        }
+    }
+    Ok(())
+}
+
 // ---------------------------------------------------------------------------
 // WS /api/events — live catalog deltas for browser/TUI subscribers (NAP-248)
 // ---------------------------------------------------------------------------

crates/maestro-daemon/src/projection.rs

@@ -0,0 +1,860 @@
+//! Fold persisted ACP notifications into client-neutral transcript and state.
+
+use std::collections::{HashMap, HashSet};
+
+use maestro_acp::schema::{ContentChunk, SessionNotification, SessionUpdate, ToolCall};
+use maestro_protocol::{
+    ActivityState, ReducedState, TranscriptDelta, TranscriptRow, TranscriptRowKind,
+    TranscriptSnapshot,
+};
+use serde_json::Value;
+
+/// A transcript delta paired with the state after the same ACP notification.
+#[derive(Debug, Clone, PartialEq)]
+pub struct ProjectionUpdate {
+    pub transcript: Option<TranscriptDelta>,
+    pub state: ReducedState,
+}
+
+/// A prompt lifecycle transition supplied by the prompt transport (#138).
+///
+/// ACP notifications do not delimit turns, so replaying them must not infer
+/// an in-flight prompt from an agent chunk.
+#[derive(Debug, Clone, Copy, PartialEq, Eq)]
+pub enum TurnLifecycle {
+    Begin,
+    Finish,
+    Cancel,
+    Failure,
+}
+
+/// The one-pass ACP fold used for both persisted replay and live events.
+#[derive(Debug, Default)]
+pub struct Projection {
+    rows: Vec<TranscriptRow>,
+    row_index: HashMap<String, usize>,
+    tools: HashMap<String, ToolCall>,
+    pending_tool_updates: HashMap<String, Vec<maestro_acp::schema::ToolCallUpdateFields>>,
+    state: ReducedState,
+    active_turn: Option<u64>,
+    turn_failed: bool,
+    next_turn: u64,
+    turn_tool_calls: HashSet<String>,
+}
+
+impl Projection {
+    /// Fold one durable event and return its client-visible changes.
+    pub fn apply(&mut self, seq: u64, notification: &SessionNotification) -> ProjectionUpdate {
+        let transcript = match &notification.update {
+            SessionUpdate::UserMessageChunk(chunk) => {
+                self.content(seq, chunk, TranscriptRowKind::User, "user")
+            }
+            SessionUpdate::AgentMessageChunk(chunk) => {
+                self.agent_text();
+                self.content(seq, chunk, TranscriptRowKind::AgentText, "agent")
+            }
+            SessionUpdate::AgentThoughtChunk(chunk) => {
+                self.agent_thought();
+                self.content(seq, chunk, TranscriptRowKind::AgentThought, "thought")
+            }
+            SessionUpdate::ToolCall(tool) => self.tool_call(tool),
+            SessionUpdate::ToolCallUpdate(update) => self.tool_update(update),
+            SessionUpdate::Plan(plan) => {
+                let data = to_value(plan);
+                self.state.plan = Some(data.clone());
+                Some(self.replace("plan".into(), TranscriptRowKind::Plan, data))
+            }
+            SessionUpdate::UsageUpdate(usage) => {
+                let value = to_value(usage);
+                self.state.usage = Some(value.clone());
+                self.state.context = Some(value);
+                None
+            }
+            SessionUpdate::CurrentModeUpdate(mode) => {
+                self.state.mode = Some(mode.current_mode_id.to_string());
+                None
+            }
+            SessionUpdate::ConfigOptionUpdate(options) => {
+                let value = to_value(options);
+                self.state.model = model_from_options(&value).or_else(|| self.state.model.clone());
+                None
+            }
+            // ACP deliberately adds notification variants over time. Known but
+            // non-transcript updates become a generic notice instead of being
+            // dropped or forcing clients to understand ACP's enum.
+            _ => Some(self.append(
+                format!("notice:{seq}"),
+                TranscriptRowKind::Notice,
+                to_value(&notification.update),
+            )),
+        };
+        ProjectionUpdate {
+            transcript,
+            state: self.state.clone(),
+        }
+    }
+
+    /// The current transcript at `cursor`.
+    pub fn snapshot(&self, cursor: u64) -> TranscriptSnapshot {
+        TranscriptSnapshot {
+            cursor,
+            rows: self.rows.clone(),
+        }
+    }
+
+    /// The state folded over every event seen so far.
+    pub fn state(&self) -> ReducedState {
+        self.state.clone()
+    }
+
+    pub fn turn_active(&self) -> bool {
+        self.active_turn.is_some()
+    }
+
+    /// Sidebar activity derived from the live turn projection.
+    pub fn activity(&self) -> ActivityState {
+        crate::activity::decide_structured(
+            self.active_turn.is_some(),
+            self.state.pending_approval.is_some(),
+            self.turn_failed,
+        )
+    }
+
+    /// Start a prompt turn and return its monotonically increasing token.
+    pub fn begin_turn(&mut self) -> (u64, ProjectionUpdate) {
+        self.next_turn += 1;
+        let turn = self.next_turn;
+        self.active_turn = Some(turn);
+        self.turn_failed = false;
+        self.state.turn.responding = true;
+        self.state.turn.thinking = true;
+        self.turn_tool_calls.clear();
+        self.state.turn.active_tool_calls.clear();
+        (
+            turn,
+            ProjectionUpdate {
+                transcript: None,
+                state: self.state(),
+            },
+        )
+    }
+
+    /// End `turn` only when it remains the active prompt turn.
+    pub fn turn_lifecycle(
+        &mut self,
+        lifecycle: TurnLifecycle,
+        turn: u64,
+    ) -> Option<ProjectionUpdate> {
+        if !matches!(
+            lifecycle,
+            TurnLifecycle::Finish | TurnLifecycle::Cancel | TurnLifecycle::Failure
+        ) || self.active_turn != Some(turn)
+        {
+            return None;
+        }
+        self.active_turn = None;
+        self.turn_failed = lifecycle == TurnLifecycle::Failure;
+        self.state.turn.responding = false;
+        self.state.turn.thinking = false;
+        self.turn_tool_calls.clear();
+        self.state.turn.active_tool_calls.clear();
+        Some(ProjectionUpdate {
+            transcript: None,
+            state: self.state(),
+        })
+    }
+
+    pub fn active_turn(&self) -> Option<u64> {
+        self.active_turn
+    }
+
+    /// Add a daemon-originated permission row. The nonce belongs only in the
+    /// reduced state, which is the client control surface, never in ACP data.
+    pub fn request_approval(&mut self, nonce: String, request: Value) -> ProjectionUpdate {
+        let row = self.append(
+            format!("approval:{}", uuid::Uuid::new_v4()),
+            TranscriptRowKind::Approval,
+            request.clone(),
+        );
+        self.state.pending_approval = Some(serde_json::json!({
+            "nonce": nonce,
+            "request": request,
+        }));
+        ProjectionUpdate {
+            transcript: Some(row),
+            state: self.state(),
+        }
+    }
+
+    pub fn restore_approval(&mut self, row: TranscriptRow) -> ProjectionUpdate {
+        let transcript = if !self.row_index.contains_key(&row.id) {
+            self.row_index.insert(row.id.clone(), self.rows.len());
+            self.rows.push(row.clone());
+            Some(TranscriptDelta::Append { row })
+        } else {
+            None
+        };
+        ProjectionUpdate {
+            transcript,
+            state: self.state(),
+        }
+    }
+
+    /// Clear an approval only when it is still the one the client answered.
+    pub fn resolve_approval(&mut self, nonce: &str) -> Option<ProjectionUpdate> {
+        let pending = self.state.pending_approval.as_ref()?;
+        if pending.get("nonce").and_then(Value::as_str) != Some(nonce) {
+            return None;
+        }
+        self.state.pending_approval = None;
+        Some(ProjectionUpdate {
+            transcript: None,
+            state: self.state(),
+        })
+    }
+
+    /// Terminal turn paths must not leave a recovered snapshot permanently
+    /// blocked on an ACP request whose transport no longer exists.
+    pub fn clear_approval(&mut self) -> Option<ProjectionUpdate> {
+        self.state.pending_approval.take()?;
+        Some(ProjectionUpdate {
+            transcript: None,
+            state: self.state(),
+        })
+    }
+
+    /// Undo an `append`ed row that a caller decides never happened — used
+    /// when persisting the row's own event fails (#184), so a snapshot taken
+    /// after the failure cannot show a row durable replay would never
+    /// reproduce. Only ever called for a row that was just appended and
+    /// never patched, so removing it by id fully reverses `append`.
+    pub fn rollback_row(&mut self, id: &str) {
+        let Some(index) = self.row_index.remove(id) else {
+            return;
+        };
+        self.rows.remove(index);
+        for (shifted_index, row) in self.rows.iter().enumerate().skip(index) {
+            self.row_index.insert(row.id.clone(), shifted_index);
+        }
+    }
+
+    fn content(
+        &mut self,
+        seq: u64,
+        chunk: &ContentChunk,
+        kind: TranscriptRowKind,
+        prefix: &str,
+    ) -> Option<TranscriptDelta> {
+        let id = chunk
+            .message_id
+            .as_ref()
+            .map(|id| format!("{prefix}:{id}"))
+            .unwrap_or_else(|| format!("{prefix}:{seq}"));
+        let data = to_value(chunk);
+        if let Some(index) = self.row_index.get(&id).copied() {
+            let row = &mut self.rows[index];
+            append_text(&mut row.data, &data);
+            return Some(TranscriptDelta::Patch { row: row.clone() });
+        }
+        Some(self.append(id, kind, data))
+    }
+
+    fn tool_call(&mut self, tool: &ToolCall) -> Option<TranscriptDelta> {
+        let id = format!("tool:{}", tool.tool_call_id);
+        let tool_id = tool.tool_call_id.to_string();
+        let mut canonical = tool.clone();
+        if let Some(updates) = self.pending_tool_updates.get(&tool_id) {
+            for fields in updates {
+                canonical.update(fields.clone());
+            }
+        }
+        let kind = if tool_has_diff(tool) {
+            TranscriptRowKind::ToolDiff
+        } else {
+            TranscriptRowKind::ToolCall
+        };
+        self.tools.insert(tool_id, canonical.clone());
+        self.track_tool_call(&canonical);
+        Some(self.replace(
+            id,
+            if tool_has_diff(&canonical) {
+                TranscriptRowKind::ToolDiff
+            } else {
+                kind
+            },
+            to_value(&canonical),
+        ))
+    }
+
+    fn tool_update(
+        &mut self,
+        update: &maestro_acp::schema::ToolCallUpdate,
+    ) -> Option<TranscriptDelta> {
+        let tool_id = update.tool_call_id.to_string();
+        let Some(tool) = self.tools.get_mut(&tool_id) else {
+            self.pending_tool_updates
+                .entry(tool_id)
+                .or_default()
+                .push(update.fields.clone());
+            return None;
+        };
+        tool.update(update.fields.clone());
+        self.pending_tool_updates
+            .entry(tool_id.clone())
+            .or_default()
+            .push(update.fields.clone());
+        let row_id = format!("tool:{tool_id}");
+        let index = *self
+            .row_index
+            .get(&row_id)
+            .expect("a tracked tool call always has a transcript row");
+        let row = {
+            let row = &mut self.rows[index];
+            row.kind = if tool_has_diff(tool) {
+                TranscriptRowKind::ToolDiff
+            } else {
+                TranscriptRowKind::ToolCall
+            };
+            row.data = to_value(tool);
+            row.clone()
+        };
+        self.sync_active_tool(&tool_id);
+        Some(TranscriptDelta::Patch { row })
+    }
+
+    fn append(&mut self, id: String, kind: TranscriptRowKind, data: Value) -> TranscriptDelta {
+        let row = TranscriptRow { id, kind, data };
+        self.row_index.insert(row.id.clone(), self.rows.len());
+        self.rows.push(row.clone());
+        TranscriptDelta::Append { row }
+    }
+
+    fn replace(&mut self, id: String, kind: TranscriptRowKind, data: Value) -> TranscriptDelta {
+        let Some(index) = self.row_index.get(&id).copied() else {
+            return self.append(id, kind, data);
+        };
+        let row = &mut self.rows[index];
+        row.kind = kind;
+        row.data = data;
+        TranscriptDelta::Patch { row: row.clone() }
+    }
+
+    fn agent_text(&mut self) {
+        if self.turn_active() {
+            self.state.turn.responding = true;
+            self.state.turn.thinking = false;
+        }
+    }
+
+    fn agent_thought(&mut self) {
+        if self.turn_active() {
+            self.state.turn.responding = true;
+            self.state.turn.thinking = true;
+        }
+    }
+
+    fn track_tool_call(&mut self, tool: &ToolCall) {
+        if self.turn_active() {
+            self.turn_tool_calls.insert(tool.tool_call_id.to_string());
+            self.sync_active_tool(&tool.tool_call_id.to_string());
+        }
+    }
+
+    fn sync_active_tool(&mut self, tool_id: &str) {
+        if !self.turn_active() || !self.turn_tool_calls.contains(tool_id) {
+            return;
+        }
+        let active = self.tools.get(tool_id).is_some_and(|tool| {
+            matches!(
+                tool.status,
+                maestro_acp::schema::ToolCallStatus::Pending
+                    | maestro_acp::schema::ToolCallStatus::InProgress
+            )
+        });
+        let active_tool_calls = &mut self.state.turn.active_tool_calls;
+        if active {
+            if !active_tool_calls.iter().any(|id| id == tool_id) {
+                active_tool_calls.push(tool_id.to_owned());
+                active_tool_calls.sort();
+            }
+        } else {
+            active_tool_calls.retain(|id| id != tool_id);
+        }
+    }
+}
+
+fn to_value(value: &impl serde::Serialize) -> Value {
+    serde_json::to_value(value).expect("ACP schema values serialize")
+}
+
+fn tool_has_diff(tool: &ToolCall) -> bool {
+    tool.content
+        .iter()
+        .any(|content| matches!(content, maestro_acp::schema::ToolCallContent::Diff(_)))
+}
+
+fn append_text(existing: &mut Value, next: &Value) {
+    let Some(existing_text) = existing.pointer_mut("/content/text") else {
+        *existing = next.clone();
+        return;
+    };
+    let Some(next_text) = next.pointer("/content/text").and_then(Value::as_str) else {
+        *existing = next.clone();
+        return;
+    };
+    if let Some(text) = existing_text.as_str() {
+        *existing_text = Value::String(format!("{text}{next_text}"));
+    } else {
+        *existing = next.clone();
+    }
+}
+
+fn model_from_options(value: &Value) -> Option<String> {
+    value
+        .get("configOptions")?
+        .as_array()?
+        .iter()
+        .find(|option| {
+            option.get("id").and_then(Value::as_str) == Some("model")
+                || option.get("category").and_then(Value::as_str) == Some("model")
+        })?
+        .get("currentValue")?
+        .as_str()
+        .map(str::to_owned)
+}
+
+#[cfg(test)]
+mod tests {
+    use maestro_acp::schema::SessionNotification;
+    use maestro_protocol::{TranscriptDelta, TranscriptRowKind};
+
+    use super::{Projection, TurnLifecycle};
+
+    fn event(value: serde_json::Value) -> SessionNotification {
+        serde_json::from_value(serde_json::json!({
+            "sessionId": "acp-1",
+            "update": value,
+        }))
+        .unwrap()
+    }
+
+    #[test]
+    fn a_session_update_tag_the_acp_dependency_does_not_know_fails_to_deserialize() {
+        // `SessionUpdate` has no unknown-variant fallback, so this never reaches `Projection::apply`.
+        let result: Result<SessionNotification, _> = serde_json::from_value(serde_json::json!({
+            "sessionId": "acp-1",
+            "update": {"sessionUpdate": "some_future_update_variant"},
+        }));
+        assert!(result.is_err());
+    }
+
+    #[test]
+    fn folds_content_tool_diff_plan_and_notice_rows() {
+        let mut projection = Projection::default();
+        let events = [
+            event(
+                serde_json::json!({"sessionUpdate":"user_message_chunk","content":{"type":"text","text":"hi"}}),
+            ),
+            event(
+                serde_json::json!({"sessionUpdate":"agent_message_chunk","content":{"type":"text","text":"hello"}}),
+            ),
+            event(
+                serde_json::json!({"sessionUpdate":"agent_thought_chunk","content":{"type":"text","text":"think"}}),
+            ),
+            event(
+                serde_json::json!({"sessionUpdate":"tool_call","toolCallId":"read-1","title":"Read","kind":"read"}),
+            ),
+            event(
+                serde_json::json!({"sessionUpdate":"tool_call","toolCallId":"edit-1","title":"Edit","content":[{"type":"diff","path":"x.rs","oldText":"a","newText":"b"}]}),
+            ),
+            event(serde_json::json!({"sessionUpdate":"plan","entries":[]})),
+            event(
+                serde_json::json!({"sessionUpdate":"available_commands_update","availableCommands":[]}),
+            ),
+        ];
+
+        let kinds: Vec<_> = events
+            .iter()
+            .enumerate()
+            .filter_map(|(i, event)| projection.apply((i + 1) as u64, event).transcript)
+            .map(|delta| match delta {
+                TranscriptDelta::Append { row } => row.kind,
+                other => panic!("expected append, got {other:?}"),
+            })
+            .collect();
+        assert_eq!(
+            kinds,
+            [
+                TranscriptRowKind::User,
+                TranscriptRowKind::AgentText,
+                TranscriptRowKind::AgentThought,
+                TranscriptRowKind::ToolCall,
+                TranscriptRowKind::ToolDiff,
+                TranscriptRowKind::Plan,
+                TranscriptRowKind::Notice,
+            ]
+        );
+    }
+
+    #[test]
+    fn tool_update_patches_the_original_stable_row() {
+        let mut projection = Projection::default();
+        let first = projection.apply(
+            4,
+            &event(serde_json::json!({
+                "sessionUpdate":"tool_call", "toolCallId":"bash-7", "title":"Run"
+            })),
+        );
+        let updated = projection.apply(
+            5,
+            &event(serde_json::json!({
+                "sessionUpdate":"tool_call_update", "toolCallId":"bash-7", "status":"completed"
+            })),
+        );
+        let id = match first.transcript.unwrap() {
+            TranscriptDelta::Append { row } => row.id,
+            other => panic!("expected append, got {other:?}"),
+        };
+        match updated.transcript.unwrap() {
+            TranscriptDelta::Patch { row } => {
+                assert_eq!(row.id, id);
+                assert_eq!(row.data["status"], "completed");
+            }
+            other => panic!("expected patch, got {other:?}"),
+        }
+        assert_eq!(projection.snapshot(5).rows.len(), 1);
+    }
+
+    #[test]
+    fn duplicate_tool_calls_patch_one_stable_row() {
+        let mut projection = Projection::default();
+        projection.apply(
+            1,
+            &event(serde_json::json!({
+                "sessionUpdate":"tool_call", "toolCallId":"bash-7", "title":"Run"
+            })),
+        );
+        let duplicate = projection.apply(
+            2,
+            &event(serde_json::json!({
+                "sessionUpdate":"tool_call", "toolCallId":"bash-7", "title":"Run again"
+            })),
+        );
+        match duplicate.transcript.unwrap() {
+            TranscriptDelta::Patch { row } => {
+                assert_eq!(row.id, "tool:bash-7");
+                assert_eq!(row.data["title"], "Run again");
+            }
+            other => panic!("expected patch, got {other:?}"),
+        }
+        assert_eq!(projection.snapshot(2).rows.len(), 1);
+    }
+
+    #[test]
+    fn early_tool_update_is_reconciled_when_the_call_arrives() {
+        let mut projection = Projection::default();
+        let early = projection.apply(
+            1,
+            &event(serde_json::json!({
+                "sessionUpdate":"tool_call_update", "toolCallId":"bash-7", "status":"completed"
+            })),
+        );
+        assert_eq!(early.transcript, None);
+        let call = projection.apply(
+            2,
+            &event(serde_json::json!({
+                "sessionUpdate":"tool_call", "toolCallId":"bash-7", "title":"Run", "status":"pending"
+            })),
+        );
+        match call.transcript.unwrap() {
+            TranscriptDelta::Append { row } => {
+                assert_eq!(row.id, "tool:bash-7");
+                assert_eq!(row.data["status"], "completed");
+            }
+            other => panic!("expected append, got {other:?}"),
+        }
+        assert!(projection.state().turn.active_tool_calls.is_empty());
+    }
+
+    #[test]
+    fn unknown_tool_stays_generic_and_keeps_its_raw_name() {
+        let mut projection = Projection::default();
+        let update = projection.apply(
+            1,
+            &event(serde_json::json!({
+                "sessionUpdate":"tool_call", "toolCallId":"custom-1", "title":"Custom",
+                "name":"vendor.custom", "kind":"future_kind"
+            })),
+        );
+        match update.transcript.unwrap() {
+            TranscriptDelta::Append { row } => {
+                assert_eq!(row.kind, TranscriptRowKind::ToolCall);
+                assert_eq!(row.data["name"], "vendor.custom");
+            }
+            other => panic!("expected generic tool row, got {other:?}"),
+        }
+    }
+
+    #[test]
+    fn folds_usage_mode_model_and_plan_into_whole_state() {
+        let mut projection = Projection::default();
+        for (seq, update) in [
+            serde_json::json!({"sessionUpdate":"usage_update","used":12,"size":200}),
+            serde_json::json!({"sessionUpdate":"current_mode_update","currentModeId":"plan"}),
+            serde_json::json!({"sessionUpdate":"config_option_update","configOptions":[{"id":"model","name":"Model","category":"model","type":"select","currentValue":"opus","options":[]}]}),
+            serde_json::json!({"sessionUpdate":"plan","entries":[]}),
+        ]
+        .into_iter()
+        .enumerate()
+        {
+            projection.apply((seq + 1) as u64, &event(update));
+        }
+        let state = projection.state();
+        assert_eq!(state.usage.as_ref().unwrap()["used"], 12);
+        assert_eq!(state.context.as_ref().unwrap()["size"], 200);
+        assert_eq!(state.mode.as_deref(), Some("plan"));
+        assert_eq!(state.model.as_deref(), Some("opus"));
+        assert_eq!(
+            state.plan.as_ref().unwrap()["entries"],
+            serde_json::json!([])
+        );
+    }
+
+    #[test]
+    fn plans_replace_one_stable_row_and_state() {
+        let mut projection = Projection::default();
+        let first = projection.apply(
+            1,
+            &event(serde_json::json!({"sessionUpdate":"plan","entries":[{"content":"first","priority":"high","status":"pending"}]})),
+        );
+        assert!(matches!(
+            first.transcript,
+            Some(TranscriptDelta::Append { .. })
+        ));
+        let replacement = projection.apply(
+            2,
+            &event(serde_json::json!({"sessionUpdate":"plan","entries":[{"content":"second","priority":"high","status":"completed"}]})),
+        );
+        match replacement.transcript.unwrap() {
+            TranscriptDelta::Patch { row } => {
+                assert_eq!(row.id, "plan");
+                assert_eq!(row.data["entries"][0]["content"], "second");
+            }
+            other => panic!("expected patch, got {other:?}"),
+        }
+        assert_eq!(projection.snapshot(2).rows.len(), 1);
+        assert_eq!(
+            projection.state().plan.unwrap()["entries"][0]["content"],
+            "second"
+        );
+    }
+
+    #[test]
+    fn turn_lifecycle_gates_chunks_and_normalizes_terminal_states() {
+        let mut projection = Projection::default();
+        projection.apply(
+            1,
+            &event(serde_json::json!({"sessionUpdate":"agent_message_chunk","content":{"type":"text","text":"replay"}})),
+        );
+        assert_eq!(projection.state().turn, Default::default());
+
+        let (_, _) = projection.begin_turn();
+        assert!(projection.state().turn.responding);
+        assert!(projection.state().turn.thinking);
+        projection.apply(
+            2,
+            &event(serde_json::json!({"sessionUpdate":"agent_thought_chunk","content":{"type":"text","text":"think"}})),
+        );
+        assert!(projection.state().turn.thinking);
+        projection.apply(
+            3,
+            &event(serde_json::json!({"sessionUpdate":"agent_message_chunk","content":{"type":"text","text":"answer"}})),
+        );
+        assert!(projection.state().turn.responding);
+        assert!(!projection.state().turn.thinking);
+
+        for terminal in [
+            TurnLifecycle::Finish,
+            TurnLifecycle::Cancel,
+            TurnLifecycle::Failure,
+        ] {
+            let (turn, _) = projection.begin_turn();
+            projection.turn_lifecycle(terminal, turn);
+            assert!(!projection.state().turn.responding);
+            assert!(!projection.state().turn.thinking);
+        }
+    }
+
+    fn terminal_turn_drops_unfinished_tools(
+        terminal: TurnLifecycle,
+        unfinished_id: &str,
+        next_id: &str,
+    ) {
+        let mut projection = Projection::default();
+        let (turn, _) = projection.begin_turn();
+        projection.apply(
+            1,
+            &event(serde_json::json!({
+                "sessionUpdate":"tool_call", "toolCallId":unfinished_id,
+                "title":"Unfinished", "status":"in_progress"
+            })),
+        );
+        assert_eq!(projection.state().turn.active_tool_calls, [unfinished_id]);
+
+        projection.turn_lifecycle(terminal, turn);
+        assert!(projection.state().turn.active_tool_calls.is_empty());
+        assert_eq!(projection.snapshot(1).rows.len(), 1);
+
+        projection.begin_turn();
+        projection.apply(
+            2,
+            &event(serde_json::json!({
+                "sessionUpdate":"tool_call", "toolCallId":next_id,
+                "title":"Next", "status":"pending"
+            })),
+        );
+        assert_eq!(projection.state().turn.active_tool_calls, [next_id]);
+    }
+
+    #[test]
+    fn cancelled_turn_does_not_reactivate_unfinished_tools() {
+        terminal_turn_drops_unfinished_tools(TurnLifecycle::Cancel, "cancelled-1", "next-1");
+    }
+
+    #[test]
+    fn failed_turn_does_not_reactivate_unfinished_tools() {
+        terminal_turn_drops_unfinished_tools(TurnLifecycle::Failure, "failed-1", "next-1");
+    }
+
+    #[test]
+    fn approval_history_survives_pending_cleanup() {
+        let mut projection = Projection::default();
+        let update =
+            projection.request_approval("secret".into(), serde_json::json!({"tool":"bash"}));
+        let TranscriptDelta::Append { row } = update.transcript.unwrap() else {
+            panic!("approval row")
+        };
+        assert_eq!(row.kind, TranscriptRowKind::Approval);
+        assert!(row.data.get("nonce").is_none());
+        assert!(!row.id.contains("secret"));
+        let persisted =
+            serde_json::to_string(&crate::sidecar::PersistedEvent::Approval { row: row.clone() })
+                .unwrap();
+        assert!(!persisted.contains("secret"));
+        assert_eq!(
+            projection.state().pending_approval.unwrap()["nonce"],
+            "secret"
+        );
+        projection.clear_approval();
+        assert!(projection.state().pending_approval.is_none());
+        assert_eq!(projection.snapshot(0).rows, vec![row]);
+    }
+
+    #[test]
+    fn rollback_row_removes_only_that_row_and_keeps_others_addressable() {
+        let mut projection = Projection::default();
+        projection.apply(
+            1,
+            &event(serde_json::json!({
+                "sessionUpdate": "user_message_chunk",
+                "messageId": "m1",
+                "content": {"type": "text", "text": "hi"},
+            })),
+        );
+        let TranscriptDelta::Append { row } = projection
+            .request_approval("nonce".into(), serde_json::json!({"tool": "bash"}))
+            .transcript
+            .unwrap()
+        else {
+            panic!("approval row")
+        };
+        // A row after the one being rolled back, so removing the approval
+        // (index 1) shifts this one from index 2 down to index 1 — proving
+        // `row_index` gets reindexed, not just `rows`.
+        projection.apply(
+            2,
+            &event(serde_json::json!({
+                "sessionUpdate": "user_message_chunk",
+                "messageId": "m2",
+                "content": {"type": "text", "text": "hey"},
+            })),
+        );
+        assert_eq!(projection.snapshot(0).rows.len(), 3);
+
+        projection.rollback_row(&row.id);
+
+        assert_eq!(projection.snapshot(0).rows.len(), 2);
+        assert_eq!(projection.snapshot(0).rows[0].kind, TranscriptRowKind::User);
+        assert_eq!(projection.snapshot(0).rows[1].kind, TranscriptRowKind::User);
+
+        // The shifted row must still be independently patchable at its new
+        // index.
+        let update = projection.apply(
+            3,
+            &event(serde_json::json!({
+                "sessionUpdate": "user_message_chunk",
+                "messageId": "m2",
+                "content": {"type": "text", "text": " there"},
+            })),
+        );
+        let TranscriptDelta::Patch { row } = update.transcript.unwrap() else {
+            panic!("patched row")
+        };
+        assert_eq!(row.data.pointer("/content/text").unwrap(), "hey there");
+        assert_eq!(projection.snapshot(0).rows.len(), 2);
+    }
+
+    #[test]
+    fn rollback_row_is_a_no_op_for_an_unknown_id() {
+        let mut projection = Projection::default();
+        projection.apply(
+            1,
+            &event(serde_json::json!({
+                "sessionUpdate": "user_message_chunk",
+                "content": {"type": "text", "text": "hi"},
+            })),
+        );
+        projection.rollback_row("approval:does-not-exist");
+        assert_eq!(projection.snapshot(0).rows.len(), 1);
+    }
+
+    #[test]
+    fn recovered_approval_is_historical_not_pending() {
+        let mut live = Projection::default();
+        let TranscriptDelta::Append { row } = live
+            .request_approval("daemon-nonce".into(), serde_json::json!({"tool":"bash"}))
+            .transcript
+            .unwrap()
+        else {
+            panic!("approval row")
+        };
+        let mut recovered = Projection::default();
+        let update = recovered.restore_approval(row.clone());
+        assert_eq!(
+            update.transcript,
+            Some(TranscriptDelta::Append { row: row.clone() })
+        );
+        assert!(update.state.pending_approval.is_none());
+        assert_eq!(recovered.snapshot(0).rows, vec![row]);
+        let replay = serde_json::to_string(&recovered.snapshot(1).rows).unwrap();
+        assert!(!replay.contains("daemon-nonce"));
+    }
+
+    #[test]
+    fn stale_terminal_turn_cannot_clear_newer_approval() {
+        let mut projection = Projection::default();
+        let (first, _) = projection.begin_turn();
+        projection.turn_lifecycle(TurnLifecycle::Cancel, first);
+        let (second, _) = projection.begin_turn();
+        projection.request_approval("second-nonce".into(), serde_json::json!({"tool":"bash"}));
+
+        assert!(projection
+            .turn_lifecycle(TurnLifecycle::Finish, first)
+            .is_none());
+        assert_eq!(projection.active_turn(), Some(second));
+        assert_eq!(
+            projection.state().pending_approval.unwrap()["nonce"],
+            "second-nonce"
+        );
+    }
+}

crates/maestro-daemon/src/sidecar.rs

@@ -5,10 +5,23 @@
 //! original `cwd`, command, env, metadata, etc. Files are deleted on
 //! `KillSession`. Sessions whose sidecar is missing at recovery time are still
 //! advertised but with empty metadata (handled by the caller, not here).
+//!
+//! A structured session (#135) also owns `<id>.events.jsonl` next to its
+//! sidecar: every `session/update` notification and daemon approval row is one
+//! JSON object, appended before it is broadcast. The log is the source of
+//! truth for the transcript; `seq` is the line's 1-based position, so a
+//! client that holds seq `n` asks for [`EventCursor::Since`]`(n)`. A line
+//! that does not parse — including the partial line a hard kill leaves at
+//! the end — keeps its seq and is skipped on read. `delete` removes the log
+//! with the sidecar; `load_all` never reads one as a sidecar.
 
+use std::collections::VecDeque;
+use std::fs::{File, OpenOptions};
+use std::io::{BufRead, BufReader, Read, Seek, SeekFrom, Write};
 use std::path::{Path, PathBuf};
 
-use maestro_protocol::Session;
+use maestro_acp::schema::SessionNotification;
+use maestro_protocol::{Session, TranscriptRow};
 use uuid::Uuid;
 
 #[derive(Debug, thiserror::Error)]
@@ -38,6 +51,120 @@ impl SidecarStore {
         self.dir.join(format!("{id}.json"))
     }
 
+    /// Where the per-session event log lives (#135).
+    pub fn events_path_for(&self, id: Uuid) -> PathBuf {
+        self.dir.join(format!("{id}.events.jsonl"))
+    }
+
+    /// Durable evidence that graceful daemon shutdown ended this structured
+    /// session and the next daemon may resume it.
+    pub fn recovery_path_for(&self, id: Uuid) -> PathBuf {
+        self.dir.join(format!("{id}.recover"))
+    }
+
+    /// Mark `id` as eligible for one structured-session recovery attempt.
+    pub fn mark_for_recovery(&self, id: Uuid) -> Result<(), SidecarError> {
+        std::fs::create_dir_all(&self.dir)?;
+        std::fs::write(self.recovery_path_for(id), [])?;
+        Ok(())
+    }
+
+    /// Consume the graceful-shutdown recovery marker for `id`.
+    pub fn take_recovery_marker(&self, id: Uuid) -> Result<bool, SidecarError> {
+        match std::fs::remove_file(self.recovery_path_for(id)) {
+            Ok(()) => Ok(true),
+            Err(error) if error.kind() == std::io::ErrorKind::NotFound => Ok(false),
+            Err(error) => Err(error.into()),
+        }
+    }
+
+    /// Open the event log for `id` for appending, creating it (and the
+    /// directory) when missing. One handle per live session: the caller
+    /// keeps it for the session's lifetime rather than reopening per
+    /// notification.
+    ///
+    /// A log whose last line has no newline — what a hard kill mid-write
+    /// leaves behind — is terminated first, so the next append starts a
+    /// fresh line instead of gluing onto the fragment. The fragment keeps
+    /// the seq of its line and reads as malformed.
+    pub fn open_events(&self, id: Uuid) -> Result<EventLog, SidecarError> {
+        std::fs::create_dir_all(&self.dir)?;
+        let mut file = OpenOptions::new()
+            .create(true)
+            .read(true)
+            .append(true)
+            .open(self.events_path_for(id))?;
+        let mut lines = 0u64;
+        let mut last = None;
+        let mut reader = BufReader::new(&mut file);
+        let mut buf = [0u8; 64 * 1024];
+        loop {
+            let n = reader.read(&mut buf)?;
+            if n == 0 {
+                break;
+            }
+            lines += buf[..n].iter().filter(|&&b| b == b'\n').count() as u64;
+            last = Some(buf[n - 1]);
+        }
+        if last.is_some_and(|b| b != b'\n') {
+            file.write_all(b"\n")?;
+            lines += 1;
+        }
+        file.seek(SeekFrom::End(0))?;
+        Ok(EventLog {
+            file: Box::new(file),
+            last_seq: lines,
+        })
+    }
+
+    /// Read events from the log for `id`, at most `limit`, in ascending seq
+    /// order. A missing log is an empty log. Lines that fail to parse are
+    /// skipped but still consume a seq, so cursors stay stable.
+    pub fn read_events(
+        &self,
+        id: Uuid,
+        cursor: EventCursor,
+        limit: usize,
+    ) -> Result<Vec<LoggedEvent>, SidecarError> {
+        let file = match File::open(self.events_path_for(id)) {
+            Ok(f) => f,
+            Err(e) if e.kind() == std::io::ErrorKind::NotFound => return Ok(Vec::new()),
+            Err(e) => return Err(e.into()),
+        };
+        if limit == 0 {
+            return Ok(Vec::new());
+        }
+        let mut out: VecDeque<LoggedEvent> = VecDeque::new();
+        let mut seq = 0u64;
+        for line in BufReader::new(file).split(b'\n') {
+            let line = line?;
+            seq += 1;
+            let keep = match cursor {
+                EventCursor::Since(since) => seq > since,
+                EventCursor::Before(Some(before)) => seq < before,
+                EventCursor::Before(None) => true,
+            };
+            if !keep {
+                if matches!(cursor, EventCursor::Before(Some(_))) {
+                    break;
+                }
+                continue;
+            }
+            let Ok(event) = PersistedEvent::decode(&line) else {
+                continue;
+            };
+            out.push_back(LoggedEvent { seq, event });
+            match cursor {
+                EventCursor::Since(_) if out.len() >= limit => break,
+                EventCursor::Before(_) if out.len() > limit => {
+                    out.pop_front();
+                }
+                _ => {}
+            }
+        }
+        Ok(out.into())
+    }
+
     /// Atomically write `session` to `<dir>/<id>.json`. Creates the directory
     /// if it does not exist.
     pub fn write(&self, session: &Session) -> Result<(), SidecarError> {
@@ -59,13 +186,13 @@ impl SidecarStore {
         }
     }
 
-    /// Delete the sidecar for `id`. No-op if it does not exist.
+    /// Delete the sidecar, event log, and recovery marker for `id`. No-op for
+    /// whichever does not exist.
     pub fn delete(&self, id: Uuid) -> Result<(), SidecarError> {
-        match std::fs::remove_file(self.path_for(id)) {
-            Ok(()) => Ok(()),
-            Err(e) if e.kind() == std::io::ErrorKind::NotFound => Ok(()),
-            Err(e) => Err(e.into()),
-        }
+        remove_if_present(&self.events_path_for(id))?;
+        remove_if_present(&self.dir.join(format!("{id}.approvals.jsonl")))?;
+        remove_if_present(&self.recovery_path_for(id))?;
+        remove_if_present(&self.path_for(id))
     }
 
     /// Read every sidecar JSON in the directory. Files that fail to parse are
@@ -81,6 +208,8 @@ impl SidecarStore {
         for entry in entries {
             let entry = entry?;
             let path = entry.path();
+            // `.events.jsonl` logs (#135) sit in the same directory and are
+            // never sidecars.
             if path.extension().and_then(|s| s.to_str()) != Some("json") {
                 continue;
             }
@@ -95,3 +224,419 @@ impl SidecarStore {
         Ok(out)
     }
 }
+
+fn remove_if_present(path: &Path) -> Result<(), SidecarError> {
+    match std::fs::remove_file(path) {
+        Ok(()) => Ok(()),
+        Err(e) if e.kind() == std::io::ErrorKind::NotFound => Ok(()),
+        Err(e) => Err(e.into()),
+    }
+}
+
+/// Which slice of a session's event log to read.
+#[derive(Debug, Clone, Copy, PartialEq, Eq)]
+pub enum EventCursor {
+    /// Forward: events with `seq` strictly greater than the cursor, the
+    /// first `limit` of them. `Since(0)` is the whole log from the start.
+    /// What a client catching up after a reconnect asks for.
+    Since(u64),
+    /// Backward: events with `seq` strictly less than the cursor, the last
+    /// `limit` of them, still returned in ascending order. `None` means the
+    /// tail of the log, for a first paint. The next page passes the smallest
+    /// seq it received.
+    Before(Option<u64>),
+}
+
+/// One line of a session's event log.
+#[derive(Debug, Clone, PartialEq)]
+pub struct LoggedEvent {
+    /// 1-based line position in the log; the cursor for [`EventCursor`].
+    pub seq: u64,
+    pub event: PersistedEvent,
+}
+
+/// A single entry in the structured event history.
+///
+/// ACP notifications retain their original JSON representation, so existing
+/// event logs remain readable. Daemon-generated rows use an envelope so they
+/// can share the same cursor sequence without pretending to be ACP traffic.
+#[derive(Debug, Clone, PartialEq, serde::Serialize, serde::Deserialize)]
+#[serde(tag = "maestroEvent", rename_all = "snake_case")]
+pub enum PersistedEvent {
+    Approval {
+        row: TranscriptRow,
+    },
+    #[serde(skip)]
+    Notification(Box<SessionNotification>),
+}
+
+impl PersistedEvent {
+    fn decode(line: &[u8]) -> Result<Self, serde_json::Error> {
+        serde_json::from_slice::<SessionNotification>(line)
+            .map(|notification| Self::Notification(Box::new(notification)))
+            .or_else(|_| serde_json::from_slice(line))
+    }
+}
+
+impl From<SessionNotification> for PersistedEvent {
+    fn from(notification: SessionNotification) -> Self {
+        Self::Notification(Box::new(notification))
+    }
+}
+
+impl From<&SessionNotification> for PersistedEvent {
+    fn from(notification: &SessionNotification) -> Self {
+        Self::Notification(Box::new(notification.clone()))
+    }
+}
+
+impl From<&PersistedEvent> for PersistedEvent {
+    fn from(event: &PersistedEvent) -> Self {
+        event.clone()
+    }
+}
+
+/// What an [`EventLog`] appends onto: something seekable by length and
+/// truncatable back to one, so a failed append can be rolled off the end
+/// again. A real [`File`] in production; an in-memory fault double in tests
+/// (#184) — the same [`EventLog::append`] rollback logic runs over both, so
+/// the behavior under test is the production behavior, not a stand-in for
+/// it.
+pub(crate) trait LogSink: Write + Send {
+    fn len(&mut self) -> std::io::Result<u64>;
+    fn truncate(&mut self, len: u64) -> std::io::Result<()>;
+}
+
+impl LogSink for File {
+    fn len(&mut self) -> std::io::Result<u64> {
+        Ok(self.metadata()?.len())
+    }
+
+    fn truncate(&mut self, len: u64) -> std::io::Result<()> {
+        self.set_len(len)
+    }
+}
+
+/// Outcome of a failed [`EventLog::append`].
+#[derive(Debug, thiserror::Error)]
+pub enum AppendError {
+    /// The write or flush failed, but the log was rolled back to exactly the
+    /// byte it was at before the call: `last_seq` and the file agree, and
+    /// this same [`EventLog`] is safe to keep appending to. The event itself
+    /// was never persisted or broadcast.
+    #[error("event append failed, rolled back cleanly: {0}")]
+    Failed(#[source] SidecarError),
+    /// The append failed *and* the rollback did not restore the log to its
+    /// prior length, so the file's line count and `last_seq` may now
+    /// disagree. The caller must not append to this [`EventLog`] again —
+    /// treat the session as dead rather than promise consistency it cannot
+    /// keep.
+    #[error("event append failed ({cause}) and rollback did not restore consistency ({rollback})")]
+    Fatal {
+        cause: SidecarError,
+        rollback: SidecarError,
+    },
+}
+
+impl From<SidecarError> for AppendError {
+    fn from(error: SidecarError) -> Self {
+        AppendError::Failed(error)
+    }
+}
+
+/// An open, append-only handle on one session's event log. Obtained from
+/// [`SidecarStore::open_events`]; held for the session's lifetime.
+pub struct EventLog {
+    file: Box<dyn LogSink>,
+    last_seq: u64,
+}
+
+impl std::fmt::Debug for EventLog {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        f.debug_struct("EventLog")
+            .field("last_seq", &self.last_seq)
+            .finish_non_exhaustive()
+    }
+}
+
+impl EventLog {
+    /// Wrap an arbitrary sink as an [`EventLog`], for tests that need to
+    /// inject a deterministic append failure (#184) — a partial write, a
+    /// flush that fails after the bytes are already down, or a rollback that
+    /// cannot itself complete.
+    #[cfg(test)]
+    pub(crate) fn for_test(file: impl LogSink + 'static, last_seq: u64) -> Self {
+        Self {
+            file: Box::new(file),
+            last_seq,
+        }
+    }
+
+    /// The seq of the last line, `0` for an empty log.
+    pub fn last_seq(&self) -> u64 {
+        self.last_seq
+    }
+
+    /// Append one notification as a line and return its seq. The line is
+    /// handed to the kernel in a single write before this returns, so a
+    /// caller that broadcasts afterwards never announces an event the log
+    /// would not replay — short of the machine losing power.
+    ///
+    /// A `write_all` that errors partway can leave an unterminated prefix on
+    /// disk; a `flush` that errors after a *complete* `write_all` leaves
+    /// ambiguity about whether that full, well-formed line should count —
+    /// counting it would silently shift every later seq by one, since
+    /// `last_seq` was never bumped for it. Both cases are rolled back to the
+    /// exact pre-append length before returning, so `last_seq` and the file
+    /// never disagree and the same [`EventLog`] can be appended to again
+    /// immediately. If the rollback itself fails, the log's consistency can
+    /// no longer be promised and [`AppendError::Fatal`] is returned instead.
+    pub fn append(&mut self, event: impl Into<PersistedEvent>) -> Result<u64, AppendError> {
+        let event = event.into();
+        let mut line = match &event {
+            PersistedEvent::Notification(notification) => serde_json::to_vec(notification)
+                .map_err(|e| AppendError::from(SidecarError::from(e)))?,
+            _ => {
+                serde_json::to_vec(&event).map_err(|e| AppendError::from(SidecarError::from(e)))?
+            }
+        };
+        line.push(b'\n');
+
+        let pre_len = self
+            .file
+            .len()
+            .map_err(|e| AppendError::from(SidecarError::from(e)))?;
+
+        if let Err(cause) = self.file.write_all(&line) {
+            return Err(self.rollback_after(pre_len, cause));
+        }
+        if let Err(cause) = self.file.flush() {
+            return Err(self.rollback_after(pre_len, cause));
+        }
+
+        self.last_seq += 1;
+        Ok(self.last_seq)
+    }
+
+    fn rollback_after(&mut self, pre_len: u64, cause: std::io::Error) -> AppendError {
+        match self.file.truncate(pre_len) {
+            Ok(()) => AppendError::Failed(SidecarError::Io(cause)),
+            Err(rollback) => AppendError::Fatal {
+                cause: SidecarError::Io(cause),
+                rollback: SidecarError::Io(rollback),
+            },
+        }
+    }
+}
+
+/// Bytes shared between a [`FaultyLogSink`] moved into an [`EventLog`] and
+/// the test that planted it, so the test can inspect what actually ended up
+/// on the "disk" after a fault without reaching into `EventLog`'s private
+/// `file` field.
+#[cfg(test)]
+#[derive(Clone, Default)]
+pub(crate) struct SharedBuf(std::sync::Arc<std::sync::Mutex<Vec<u8>>>);
+
+#[cfg(test)]
+impl SharedBuf {
+    pub(crate) fn snapshot(&self) -> Vec<u8> {
+        self.0.lock().unwrap().clone()
+    }
+}
+
+/// An in-memory [`LogSink`] double that injects one deterministic fault — a
+/// short write, a flush that fails after a full write, or a rollback that
+/// cannot itself complete — then behaves like a healthy sink from then on.
+/// Lets a test prove the *same* [`EventLog`] recovers, rather than one with a
+/// handle swapped in from a healthy disk, which production never does
+/// (#184).
+#[cfg(test)]
+#[derive(Default)]
+pub(crate) struct FaultyLogSink {
+    pub(crate) buf: SharedBuf,
+    /// Accept this many bytes on the next `write` call, then fail the
+    /// *following* call — a short write followed by an error, exactly what
+    /// `write_all` sees from a real fd that dies mid-line. `Write::write`
+    /// must not report an error on a call that made partial progress, so
+    /// the fault is delivered one call later, via `pending_write_error`.
+    pub(crate) fail_write_after: Option<usize>,
+    pub(crate) pending_write_error: bool,
+    pub(crate) fail_flush_once: bool,
+    pub(crate) fail_truncate: bool,
+}
+
+#[cfg(test)]
+impl Write for FaultyLogSink {
+    fn write(&mut self, data: &[u8]) -> std::io::Result<usize> {
+        if self.pending_write_error {
+            self.pending_write_error = false;
+            return Err(std::io::Error::other("fault: write failed mid-line"));
+        }
+        if let Some(allowed) = self.fail_write_after.take() {
+            let allowed = allowed.min(data.len());
+            if allowed == 0 {
+                // No progress was made, so it's fine to report the error
+                // from this same call.
+                return Err(std::io::Error::other("fault: write failed mid-line"));
+            }
+            self.buf
+                .0
+                .lock()
+                .unwrap()
+                .extend_from_slice(&data[..allowed]);
+            self.pending_write_error = true;
+            return Ok(allowed);
+        }
+        self.buf.0.lock().unwrap().extend_from_slice(data);
+        Ok(data.len())
+    }
+
+    fn flush(&mut self) -> std::io::Result<()> {
+        if self.fail_flush_once {
+            self.fail_flush_once = false;
+            return Err(std::io::Error::other(
+                "fault: flush failed after a full write",
+            ));
+        }
+        Ok(())
+    }
+}
+
+#[cfg(test)]
+impl LogSink for FaultyLogSink {
+    fn len(&mut self) -> std::io::Result<u64> {
+        Ok(self.buf.0.lock().unwrap().len() as u64)
+    }
+
+    fn truncate(&mut self, len: u64) -> std::io::Result<()> {
+        if self.fail_truncate {
+            return Err(std::io::Error::other("fault: rollback truncate failed"));
+        }
+        self.buf.0.lock().unwrap().truncate(len as usize);
+        Ok(())
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    fn sample_event(id: &str) -> PersistedEvent {
+        PersistedEvent::Approval {
+            row: TranscriptRow {
+                id: id.to_owned(),
+                kind: maestro_protocol::TranscriptRowKind::Approval,
+                data: serde_json::json!({"tool": "bash"}),
+            },
+        }
+    }
+
+    /// Replays `bytes` as a real on-disk log via the production read path,
+    /// so "live and durable agree" is checked with the same code a
+    /// reconnecting client would hit, not a hand-rolled line splitter.
+    fn replay(bytes: &[u8]) -> Vec<LoggedEvent> {
+        let dir = tempfile::tempdir().unwrap();
+        let store = SidecarStore::new(dir.path());
+        let id = Uuid::new_v4();
+        std::fs::create_dir_all(store.dir()).unwrap();
+        std::fs::write(store.events_path_for(id), bytes).unwrap();
+        store.read_events(id, EventCursor::Since(0), 100).unwrap()
+    }
+
+    #[test]
+    fn append_rolls_back_a_partial_write_and_the_same_instance_recovers() {
+        let buf = SharedBuf::default();
+        let writer = FaultyLogSink {
+            buf: buf.clone(),
+            fail_write_after: Some(5),
+            ..Default::default()
+        };
+        let mut log = EventLog::for_test(writer, 0);
+
+        let err = log.append(sample_event("r1")).unwrap_err();
+        assert!(
+            matches!(err, AppendError::Failed(_)),
+            "a repairable rollback must not be reported fatal"
+        );
+        assert_eq!(log.last_seq(), 0, "cursor must stay put on a failed append");
+        assert!(
+            buf.snapshot().is_empty(),
+            "the partial prefix a failed write_all leaves behind must be truncated away"
+        );
+
+        let seq = log
+            .append(sample_event("r1"))
+            .expect("the same instance must be able to append again after a clean rollback");
+        assert_eq!(seq, 1);
+        assert_eq!(log.last_seq(), 1);
+
+        let bytes = buf.snapshot();
+        assert_eq!(
+            bytes.iter().filter(|&&b| b == b'\n').count(),
+            1,
+            "exactly one well-formed line, not a partial prefix glued to the recovered append"
+        );
+
+        let replayed = replay(&bytes);
+        assert_eq!(replayed.len(), 1);
+        assert_eq!(replayed[0].seq, log.last_seq());
+        let PersistedEvent::Approval { row } = &replayed[0].event else {
+            panic!("approval event");
+        };
+        assert_eq!(row.id, "r1");
+    }
+
+    #[test]
+    fn append_rolls_back_when_flush_fails_after_a_full_write() {
+        let buf = SharedBuf::default();
+        let writer = FaultyLogSink {
+            buf: buf.clone(),
+            fail_flush_once: true,
+            ..Default::default()
+        };
+        let mut log = EventLog::for_test(writer, 0);
+
+        let err = log.append(sample_event("r1")).unwrap_err();
+        assert!(matches!(err, AppendError::Failed(_)));
+        assert_eq!(log.last_seq(), 0);
+        assert!(
+            buf.snapshot().is_empty(),
+            "a full-but-unflushed line must not survive uncounted by last_seq — it would \
+             silently shift every later seq by one"
+        );
+
+        let seq = log
+            .append(sample_event("r1"))
+            .expect("the same instance must recover once flush stops failing");
+        assert_eq!(seq, 1);
+
+        let bytes = buf.snapshot();
+        let replayed = replay(&bytes);
+        assert_eq!(replayed.len(), 1);
+        assert_eq!(replayed[0].seq, log.last_seq());
+    }
+
+    #[test]
+    fn append_reports_fatal_when_rollback_cannot_restore_consistency() {
+        let buf = SharedBuf::default();
+        let writer = FaultyLogSink {
+            buf,
+            fail_write_after: Some(3),
+            fail_truncate: true,
+            ..Default::default()
+        };
+        let mut log = EventLog::for_test(writer, 0);
+
+        let err = log.append(sample_event("r1")).unwrap_err();
+        assert!(
+            matches!(err, AppendError::Fatal { .. }),
+            "an unrepairable rollback must be surfaced as fatal, never silently treated as \
+             a clean recoverable failure"
+        );
+        assert_eq!(
+            log.last_seq(),
+            0,
+            "a fatal append must not advance the cursor either"
+        );
+    }
+}

crates/maestro-daemon/src/viewport.rs

@@ -0,0 +1,186 @@
+//! What size the shared tmux window should be, given every client watching it.
+//!
+//! A tmux window has one size, but a session can have several clients attached
+//! at once — two browser panes, a browser and the TUI. Each reports the size
+//! *it* can display, and applying whichever arrived last makes the window
+//! flip-flop. Every flip forces a full-screen application (Claude Code, vim) to
+//! repaint at a new height, and the rows it drew at the old height are never
+//! cleared: the operator ends up looking at a stale input box, types into a
+//! box that is not where the screen says it is, and concludes the pane is
+//! stuck.
+//!
+//! So the window is sized to the smallest attached client on each axis — the
+//! same rule tmux uses for its own multiple clients, and the only size every
+//! client can render without truncation. The size last handed to tmux is
+//! remembered, so a report that changes nothing costs no `tmux` fork at all.
+
+use std::collections::HashMap;
+
+use uuid::Uuid;
+
+/// One attached client within a session. Allocated by
+/// [`crate::session::SessionManager`] and opaque to everything else.
+pub type ViewportId = u64;
+
+/// Per-session client sizes, and what tmux was last told.
+#[derive(Debug, Default)]
+pub struct Viewports {
+    clients: HashMap<Uuid, HashMap<ViewportId, (u16, u16)>>,
+    applied: HashMap<Uuid, (u16, u16)>,
+}
+
+impl Viewports {
+    pub fn new() -> Self {
+        Self::default()
+    }
+
+    /// Record what `viewport` can display. Returns the size tmux must be set
+    /// to, or `None` when the window already has it.
+    pub fn set(
+        &mut self,
+        session: Uuid,
+        viewport: ViewportId,
+        cols: u16,
+        rows: u16,
+    ) -> Option<(u16, u16)> {
+        self.clients
+            .entry(session)
+            .or_default()
+            .insert(viewport, (cols, rows));
+        self.settle(session)
+    }
+
+    /// Drop a client that has detached. Returns the size tmux must be set to
+    /// now that it no longer constrains the window.
+    ///
+    /// The last client leaving settles nothing: the window keeps the size it
+    /// has rather than snapping to some remembered default no one is watching.
+    pub fn release(&mut self, session: Uuid, viewport: ViewportId) -> Option<(u16, u16)> {
+        let clients = self.clients.get_mut(&session)?;
+        clients.remove(&viewport);
+        if clients.is_empty() {
+            self.clients.remove(&session);
+            self.applied.remove(&session);
+            return None;
+        }
+        self.settle(session)
+    }
+
+    /// The smallest size every attached client can render, but only when it
+    /// differs from what tmux was last told.
+    ///
+    /// A zero on either axis is a client that cannot display anything yet — a
+    /// pane still laying out, a hidden tab — and must not drag the shared
+    /// window down with it, so it is held but left out of the arbitration.
+    fn settle(&mut self, session: Uuid) -> Option<(u16, u16)> {
+        let clients = self.clients.get(&session)?;
+        let mut cols = u16::MAX;
+        let mut rows = u16::MAX;
+        for &(c, r) in clients.values() {
+            if c == 0 || r == 0 {
+                continue;
+            }
+            cols = cols.min(c);
+            rows = rows.min(r);
+        }
+        if cols == u16::MAX || rows == u16::MAX {
+            return None;
+        }
+        let target = (cols, rows);
+        if self.applied.get(&session) == Some(&target) {
+            return None;
+        }
+        self.applied.insert(session, target);
+        Some(target)
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn the_first_report_settles_the_window() {
+        let mut v = Viewports::new();
+        let s = Uuid::new_v4();
+        assert_eq!(v.set(s, 1, 80, 24), Some((80, 24)));
+    }
+
+    #[test]
+    fn a_report_that_changes_nothing_costs_no_resize() {
+        let mut v = Viewports::new();
+        let s = Uuid::new_v4();
+        v.set(s, 1, 80, 24);
+        assert_eq!(v.set(s, 1, 80, 24), None);
+        assert_eq!(v.set(s, 1, 80, 24), None);
+    }
+
+    /// The bug this module exists for: two clients of different sizes used to
+    /// resize the window past each other on every report.
+    #[test]
+    fn two_clients_settle_on_the_smaller_instead_of_fighting() {
+        let mut v = Viewports::new();
+        let s = Uuid::new_v4();
+        assert_eq!(v.set(s, 1, 53, 46), Some((53, 46)));
+        assert_eq!(v.set(s, 2, 53, 20), Some((53, 20)));
+        // Whatever order they re-report in, the answer stays the smaller one.
+        assert_eq!(v.set(s, 1, 53, 46), None);
+        assert_eq!(v.set(s, 2, 53, 20), None);
+        assert_eq!(v.set(s, 1, 53, 46), None);
+    }
+
+    #[test]
+    fn each_axis_is_arbitrated_on_its_own() {
+        let mut v = Viewports::new();
+        let s = Uuid::new_v4();
+        v.set(s, 1, 200, 20);
+        assert_eq!(v.set(s, 2, 53, 46), Some((53, 20)));
+    }
+
+    #[test]
+    fn a_zero_sized_client_does_not_shrink_the_window() {
+        let mut v = Viewports::new();
+        let s = Uuid::new_v4();
+        assert_eq!(v.set(s, 1, 80, 24), Some((80, 24)));
+        assert_eq!(v.set(s, 2, 0, 0), None);
+        assert_eq!(v.set(s, 2, 0, 30), None);
+    }
+
+    #[test]
+    fn releasing_the_small_client_gives_the_window_back() {
+        let mut v = Viewports::new();
+        let s = Uuid::new_v4();
+        v.set(s, 1, 80, 46);
+        v.set(s, 2, 80, 20);
+        assert_eq!(v.release(s, 2), Some((80, 46)));
+    }
+
+    #[test]
+    fn releasing_the_last_client_settles_nothing() {
+        let mut v = Viewports::new();
+        let s = Uuid::new_v4();
+        v.set(s, 1, 80, 24);
+        assert_eq!(v.release(s, 1), None);
+        // ...and the session is forgotten, so a fresh attach settles again.
+        assert_eq!(v.set(s, 2, 80, 24), Some((80, 24)));
+    }
+
+    #[test]
+    fn releasing_an_unknown_viewport_is_harmless() {
+        let mut v = Viewports::new();
+        let s = Uuid::new_v4();
+        assert_eq!(v.release(s, 7), None);
+        v.set(s, 1, 80, 24);
+        assert_eq!(v.release(s, 7), None);
+    }
+
+    #[test]
+    fn sessions_do_not_arbitrate_against_each_other() {
+        let mut v = Viewports::new();
+        let a = Uuid::new_v4();
+        let b = Uuid::new_v4();
+        assert_eq!(v.set(a, 1, 80, 24), Some((80, 24)));
+        assert_eq!(v.set(b, 2, 53, 20), Some((53, 20)));
+        assert_eq!(v.set(a, 1, 80, 24), None);
+    }
+}

crates/maestro-daemon/src/worktree.rs

@@ -111,16 +111,33 @@ impl WorktreeManager {
         // Clear registrations whose directory is gone first, so a
         // previously-leaked entry doesn't push this branch to a suffix.
         prune(base_repo)?;
-        // Anything occupying the target — a tree we left behind, one the
-        // operator made, an unrelated directory — is sidestepped with a
-        // numeric suffix on the directory; the branch stays whatever was
-        // requested (#77). The daemon never adopts what it finds.
-        let mut path = self.target_path(base_repo, branch);
-        let mut n = 1;
-        while path.symlink_metadata().is_ok() {
-            n += 1;
-            path = self.target_path_suffixed(base_repo, branch, n);
-        }
+        let (branch, path) = if create_branch {
+            // Worktrees are commonly abandoned without deleting their branch,
+            // so a random handle can collide with one of its own past runs.
+            // Unlike the `add_existing` arm below, the suffix goes on the
+            // branch name itself — the path is derived from it anyway.
+            let mut candidate = branch.to_string();
+            let mut path = self.target_path(base_repo, &candidate);
+            let mut n = 1;
+            while path.symlink_metadata().is_ok() || branch_exists(base_repo, &candidate) {
+                n += 1;
+                candidate = format!("{branch}-{n}");
+                path = self.target_path(base_repo, &candidate);
+            }
+            (candidate, path)
+        } else {
+            // Existing branch: the name must stay exact, so only the
+            // directory — anything occupying it, ours or the operator's — is
+            // sidestepped with a numeric suffix (#77). The daemon never
+            // adopts what it finds.
+            let mut path = self.target_path(base_repo, branch);
+            let mut n = 1;
+            while path.symlink_metadata().is_ok() {
+                n += 1;
+                path = self.target_path_suffixed(base_repo, branch, n);
+            }
+            (branch.to_string(), path)
+        };
         // The parent (`<repo>/worktrees` or the override root) may not exist
         // yet; the target itself must not.
         if let Some(parent) = path.parent() {
@@ -129,10 +146,10 @@ impl WorktreeManager {
         let mut cmd = Command::new("git");
         cmd.arg("-C").arg(base_repo).args(["worktree", "add"]);
         if create_branch {
-            cmd.arg("-b").arg(branch).arg(&path);
+            cmd.arg("-b").arg(&branch).arg(&path);
         } else {
             // Existing branch: `worktree add <path> <branch>` with no `-b`.
-            cmd.arg(&path).arg(branch);
+            cmd.arg(&path).arg(&branch);
         }
         let out = cmd.output()?;
         check(out)?;
@@ -266,6 +283,17 @@ fn branch_relpath(branch: &str) -> Option<PathBuf> {
     Some(candidate.to_path_buf())
 }
 
+/// Whether `refs/heads/<branch>` already exists in `base_repo`.
+fn branch_exists(base_repo: &Path, branch: &str) -> bool {
+    Command::new("git")
+        .arg("-C")
+        .arg(base_repo)
+        .args(["show-ref", "--verify", "--quiet"])
+        .arg(format!("refs/heads/{branch}"))
+        .status()
+        .is_ok_and(|s| s.success())
+}
+
 /// `git -C <base_repo> worktree prune` — drops registrations whose directory
 /// no longer exists.
 fn prune(base_repo: &Path) -> Result<(), WorktreeError> {

crates/maestro-daemon/tests/activity_report.rs

@@ -42,6 +42,7 @@ async fn fixture(ttl: Duration) -> Fixture {
 async fn spawn_sleeping(manager: &SessionManager) -> Uuid {
     manager
         .create(CreateSessionRequest {
+            view: Default::default(),
             cwd: "/tmp".into(),
             command: "sleep 60".into(),
             env: Default::default(),

crates/maestro-daemon/tests/attach.rs

@@ -38,6 +38,7 @@ async fn spawn_daemon_ws() -> Harness {
         "/home/test",
         Vec::new(),
         std::sync::Arc::new(maestro_daemon::projects::ProjectScanner::disabled()),
+        maestro_config::DEFAULT_LEADER,
     ));
     let listener = TcpListener::bind(SocketAddr::from((Ipv4Addr::LOCALHOST, 0)))
         .await
@@ -74,6 +75,7 @@ async fn create_bash_session(h: &Harness) -> Uuid {
     let s = h
         .manager
         .create(CreateSessionRequest {
+            view: Default::default(),
             cwd: cwd_path,
             command: "bash --noprofile --norc".into(),
             env: HashMap::new(),

crates/maestro-daemon/tests/autoname.rs

@@ -50,6 +50,7 @@ async fn spawn(manager: &SessionManager, name: Option<&str>) -> Uuid {
     };
     manager
         .create(CreateSessionRequest {
+            view: Default::default(),
             cwd: "/tmp".into(),
             command: "sleep 60".into(),
             env: Default::default(),

crates/maestro-daemon/tests/blocked_work_cost.rs

@@ -19,6 +19,7 @@ use tempfile::TempDir;
 
 fn request(cwd: &std::path::Path, repo: &std::path::Path, branch: &str) -> CreateSessionRequest {
     CreateSessionRequest {
+        view: Default::default(),
         cwd: cwd.to_path_buf(),
         command: "sleep 30".into(),
         env: HashMap::new(),

crates/maestro-daemon/tests/branches.rs

@@ -27,6 +27,7 @@ async fn spawn() -> Harness {
         "/home/test",
         presets,
         Arc::new(maestro_daemon::projects::ProjectScanner::disabled()),
+        maestro_config::DEFAULT_LEADER,
     ));
     let listener = TcpListener::bind(SocketAddr::from((Ipv4Addr::LOCALHOST, 0)))
         .await

crates/maestro-daemon/tests/local_api.rs

@@ -4,12 +4,17 @@ mod common;
 
 use std::collections::HashMap;
 use std::net::{Ipv4Addr, SocketAddr};
+use std::path::Path;
 use std::time::Duration;
 
 use common::DaemonFixture;
 use futures_util::{SinkExt, StreamExt};
 use maestro_daemon::local_api;
-use maestro_protocol::{ApiError, CreateSessionRequest, Session, WorktreeSpec};
+use maestro_protocol::{
+    ActivityState, ApiError, CreateSessionRequest, Session, SessionStatus, SessionView,
+    WorktreeSpec,
+};
+use tempfile::TempDir;
 use tokio::net::TcpListener;
 use tokio::sync::oneshot;
 use tokio_tungstenite::tungstenite::Message as WsMessage;
@@ -36,6 +41,14 @@ async fn spawn(hostname: &str) -> Harness {
 async fn spawn_with(
     hostname: &str,
     projects: std::sync::Arc<maestro_daemon::projects::ProjectScanner>,
+) -> Harness {
+    spawn_with_leader(hostname, projects, maestro_config::DEFAULT_LEADER).await
+}
+
+async fn spawn_with_leader(
+    hostname: &str,
+    projects: std::sync::Arc<maestro_daemon::projects::ProjectScanner>,
+    leader: &str,
 ) -> Harness {
     let fx = DaemonFixture::new();
     let manager = fx.manager.clone();
@@ -48,6 +61,7 @@ async fn spawn_with(
         "/home/test",
         presets,
         projects,
+        leader,
     ));
     let listener = TcpListener::bind(SocketAddr::from((Ipv4Addr::LOCALHOST, 0)))
         .await
@@ -77,6 +91,589 @@ fn ws_url(addr: SocketAddr, path: &str) -> String {
     format!("ws://{addr}{path}")
 }
 
+struct FakeAcp {
+    dir: TempDir,
+}
+
+impl FakeAcp {
+    fn new() -> Self {
+        use std::os::unix::fs::PermissionsExt;
+
+        let dir = TempDir::new().unwrap();
+        let bin = dir.path().join("bin");
+        std::fs::create_dir_all(&bin).unwrap();
+        let adapter = bin.join("claude-code-acp");
+        std::fs::copy(
+            Path::new(env!("CARGO_MANIFEST_DIR")).join("../maestro-acp/tests/fake_acp_agent.py"),
+            &adapter,
+        )
+        .unwrap();
+        std::fs::set_permissions(&adapter, std::fs::Permissions::from_mode(0o755)).unwrap();
+        Self { dir }
+    }
+
+    fn env(&self) -> HashMap<String, String> {
+        HashMap::from([
+            (
+                "PATH".into(),
+                format!(
+                    "{}:{}",
+                    self.dir.path().join("bin").display(),
+                    std::env::var("PATH").unwrap()
+                ),
+            ),
+            (
+                "FAKE_ACP_LOG".into(),
+                self.dir.path().join("agent.log").display().to_string(),
+            ),
+        ])
+    }
+
+    fn pid(&self) -> u32 {
+        std::fs::read_to_string(self.dir.path().join("agent.log"))
+            .unwrap_or_default()
+            .lines()
+            .filter_map(|line| {
+                line.strip_prefix("start pid=")?
+                    .split(' ')
+                    .next()?
+                    .parse()
+                    .ok()
+            })
+            .next_back()
+            .expect("fake ACP started")
+    }
+
+    fn log(&self) -> String {
+        std::fs::read_to_string(self.dir.path().join("agent.log")).unwrap_or_default()
+    }
+}
+
+async fn structured_session(h: &Harness, fake: &FakeAcp) -> Uuid {
+    structured_session_with_env(h, fake.env()).await
+}
+
+async fn structured_session_with_env(h: &Harness, env: HashMap<String, String>) -> Uuid {
+    h.manager
+        .create(CreateSessionRequest {
+            view: SessionView::Structured,
+            cwd: "/tmp".into(),
+            command: "claude".into(),
+            env,
+            metadata: HashMap::new(),
+            worktree: None,
+        })
+        .await
+        .unwrap()
+        .id
+}
+
+async fn wait_for_session_activity(h: &Harness, id: Uuid, expected: ActivityState) {
+    tokio::time::timeout(Duration::from_secs(2), async {
+        loop {
+            let sessions: Vec<Session> = reqwest::get(url(h.addr, "/api/sessions"))
+                .await
+                .unwrap()
+                .json()
+                .await
+                .unwrap();
+            if sessions
+                .iter()
+                .find(|session| session.id == id)
+                .is_some_and(|session| session.activity == expected)
+            {
+                return;
+            }
+            tokio::time::sleep(Duration::from_millis(10)).await;
+        }
+    })
+    .await
+    .unwrap_or_else(|_| panic!("session {id} did not reach {expected:?}"));
+}
+
+#[tokio::test]
+async fn structured_ws_sends_snapshot_then_live_projection() {
+    let h = spawn("naps-laptop").await;
+    let fake = FakeAcp::new();
+    let id = structured_session(&h, &fake).await;
+    let (mut ws, _) = connect_async(ws_url(h.addr, &format!("/api/structured/{id}")))
+        .await
+        .unwrap();
+
+    let first = ws.next().await.unwrap().unwrap().into_text().unwrap();
+    let second = ws.next().await.unwrap().unwrap().into_text().unwrap();
+    assert_eq!(
+        serde_json::from_str::<serde_json::Value>(&first).unwrap()["type"],
+        "transcript_snapshot"
+    );
+    assert_eq!(
+        serde_json::from_str::<serde_json::Value>(&second).unwrap()["type"],
+        "reduced_state"
+    );
+
+    let response = reqwest::Client::new()
+        .post(url(
+            h.addr,
+            &format!("/api/sessions/{id}/structured/prompt"),
+        ))
+        .json(&serde_json::json!({"prompt": "hello"}))
+        .send()
+        .await
+        .unwrap();
+    assert_eq!(response.status(), reqwest::StatusCode::NO_CONTENT);
+    let live = tokio::time::timeout(Duration::from_secs(1), ws.next())
+        .await
+        .expect("projection update arrives on the subscribed stream")
+        .unwrap()
+        .unwrap()
+        .into_text()
+        .unwrap();
+    assert_eq!(
+        serde_json::from_str::<serde_json::Value>(&live).unwrap()["type"],
+        "projection_update"
+    );
+}
+
+#[tokio::test]
+async fn structured_prompt_rejects_a_second_in_flight_turn_and_cancel_clears_it() {
+    let h = spawn("naps-laptop").await;
+    let fake = FakeAcp::new();
+    let mut env = fake.env();
+    env.insert("FAKE_ACP_DELAY_PROMPT_MS".into(), "200".into());
+    let id = structured_session_with_env(&h, env).await;
+    let client = reqwest::Client::new();
+    let first = client
+        .post(url(
+            h.addr,
+            &format!("/api/sessions/{id}/structured/prompt"),
+        ))
+        .json(&serde_json::json!({"prompt": "first"}))
+        .send()
+        .await
+        .unwrap();
+    assert_eq!(first.status(), reqwest::StatusCode::NO_CONTENT);
+    let second = client
+        .post(url(
+            h.addr,
+            &format!("/api/sessions/{id}/structured/prompt"),
+        ))
+        .json(&serde_json::json!({"prompt": "second"}))
+        .send()
+        .await
+        .unwrap();
+    assert_eq!(second.status(), reqwest::StatusCode::CONFLICT);
+    let error: ApiError = second.json().await.unwrap();
+    assert_eq!(error.error.code, "turn_in_flight");
+
+    let cancel = client
+        .post(url(
+            h.addr,
+            &format!("/api/sessions/{id}/structured/cancel"),
+        ))
+        .send()
+        .await
+        .unwrap();
+    assert_eq!(cancel.status(), reqwest::StatusCode::NO_CONTENT);
+    let next = client
+        .post(url(
+            h.addr,
+            &format!("/api/sessions/{id}/structured/prompt"),
+        ))
+        .json(&serde_json::json!({"prompt": "next"}))
+        .send()
+        .await
+        .unwrap();
+    assert_eq!(next.status(), reqwest::StatusCode::NO_CONTENT);
+    tokio::time::timeout(Duration::from_secs(2), async {
+        loop {
+            if fake.log().matches("recv session/prompt").count() == 2 {
+                break;
+            }
+            tokio::time::sleep(Duration::from_millis(10)).await;
+        }
+    })
+    .await
+    .expect("both prompt commands reach ACP");
+    let log = fake.log();
+    let first_prompt = log.find("recv session/prompt").unwrap();
+    let cancel = log.find("recv session/cancel").unwrap();
+    let second_prompt = log.rfind("recv session/prompt").unwrap();
+    assert!(first_prompt < cancel && cancel < second_prompt, "{log}");
+}
+
+#[tokio::test]
+async fn structured_approval_is_secret_single_use_and_race_safe() {
+    let h = spawn("naps-laptop").await;
+    let fake = FakeAcp::new();
+    let mut env = fake.env();
+    env.insert("FAKE_ACP_REQUEST_PERMISSION".into(), "1".into());
+    let id = structured_session_with_env(&h, env).await;
+    let client = reqwest::Client::new();
+    let (mut ws, _) = connect_async(ws_url(h.addr, &format!("/api/structured/{id}")))
+        .await
+        .unwrap();
+    ws.next().await.unwrap().unwrap();
+    ws.next().await.unwrap().unwrap();
+    assert_eq!(
+        client
+            .post(url(
+                h.addr,
+                &format!("/api/sessions/{id}/structured/prompt")
+            ))
+            .json(&serde_json::json!({"prompt":"needs permission"}))
+            .send()
+            .await
+            .unwrap()
+            .status(),
+        reqwest::StatusCode::NO_CONTENT
+    );
+
+    let nonce = tokio::time::timeout(Duration::from_secs(2), async {
+        loop {
+            let event: serde_json::Value =
+                serde_json::from_str(&ws.next().await.unwrap().unwrap().into_text().unwrap())
+                    .unwrap();
+            if let Some(nonce) = event["state"]["pending_approval"]["nonce"].as_str() {
+                assert_eq!(event["transcript"]["row"]["kind"], "approval");
+                assert!(event["transcript"]["row"]["data"].get("nonce").is_none());
+                break nonce.to_owned();
+            }
+        }
+    })
+    .await
+    .unwrap();
+    wait_for_session_activity(&h, id, ActivityState::AwaitingInput).await;
+    assert!(
+        !fake.log().contains(&nonce),
+        "daemon nonce leaked to ACP agent"
+    );
+
+    let path = format!("/api/sessions/{id}/structured/approvals/{nonce}");
+    let (a, b) = tokio::join!(
+        client
+            .post(url(h.addr, &path))
+            .json(&serde_json::json!("allow_once"))
+            .send(),
+        client
+            .post(url(h.addr, &path))
+            .json(&serde_json::json!("deny"))
+            .send(),
+    );
+    assert_eq!(a.unwrap().status(), reqwest::StatusCode::NO_CONTENT);
+    assert_eq!(b.unwrap().status(), reqwest::StatusCode::NO_CONTENT);
+    assert_eq!(
+        client
+            .post(url(h.addr, &path))
+            .json(&serde_json::json!("deny"))
+            .send()
+            .await
+            .unwrap()
+            .status(),
+        reqwest::StatusCode::NO_CONTENT
+    );
+    tokio::time::timeout(Duration::from_secs(2), async {
+        loop {
+            if fake.log().contains("permission response") {
+                break;
+            }
+            tokio::time::sleep(Duration::from_millis(10)).await;
+        }
+    })
+    .await
+    .unwrap();
+    let log = fake.log();
+    assert!(
+        log.contains("\"optionId\": \"once\"") || log.contains("\"optionId\": \"deny\""),
+        "{log}"
+    );
+    tokio::time::timeout(Duration::from_secs(1), async {
+        loop {
+            let event: serde_json::Value =
+                serde_json::from_str(&ws.next().await.unwrap().unwrap().into_text().unwrap())
+                    .unwrap();
+            if event["state"]["pending_approval"].is_null() {
+                break;
+            }
+        }
+    })
+    .await
+    .expect("resolved approval clears the reduced state");
+    wait_for_session_activity(&h, id, ActivityState::Idle).await;
+    assert_eq!(
+        client
+            .post(url(
+                h.addr,
+                &format!(
+                    "/api/sessions/{}/structured/approvals/{nonce}",
+                    Uuid::new_v4()
+                )
+            ))
+            .json(&serde_json::json!("deny"))
+            .send()
+            .await
+            .unwrap()
+            .status(),
+        reqwest::StatusCode::NOT_FOUND
+    );
+}
+
+#[tokio::test]
+async fn structured_prompt_failure_clears_the_turn() {
+    let h = spawn("naps-laptop").await;
+    let fake = FakeAcp::new();
+    let mut env = fake.env();
+    env.insert("FAKE_ACP_PROMPT_FAIL_ONCE".into(), "1".into());
+    let id = structured_session_with_env(&h, env).await;
+    let client = reqwest::Client::new();
+    let path = format!("/api/sessions/{id}/structured/prompt");
+    let (mut ws, _) = connect_async(ws_url(h.addr, &format!("/api/structured/{id}")))
+        .await
+        .unwrap();
+    ws.next().await.unwrap().unwrap();
+    ws.next().await.unwrap().unwrap();
+    let first = client
+        .post(url(h.addr, &path))
+        .json(&serde_json::json!({"prompt":"fails"}))
+        .send()
+        .await
+        .unwrap();
+    assert_eq!(first.status(), reqwest::StatusCode::NO_CONTENT);
+    let mut saw_active_turn = false;
+    tokio::time::timeout(Duration::from_secs(1), async {
+        while let Some(Ok(message)) = ws.next().await {
+            let event: serde_json::Value =
+                serde_json::from_str(&message.into_text().unwrap()).unwrap();
+            let turn = &event["state"]["turn"];
+            if turn["responding"] == true {
+                saw_active_turn = true;
+            }
+            if saw_active_turn && turn["responding"] == false && turn["thinking"] == false {
+                return;
+            }
+        }
+        panic!("structured websocket closed before the failed turn cleared");
+    })
+    .await
+    .expect("failed turn clears promptly");
+    wait_for_session_activity(&h, id, ActivityState::Error).await;
+    let second = client
+        .post(url(h.addr, &path))
+        .json(&serde_json::json!({"prompt":"available"}))
+        .send()
+        .await
+        .unwrap();
+    assert_eq!(second.status(), reqwest::StatusCode::NO_CONTENT);
+    assert!(second.bytes().await.unwrap().is_empty());
+}
+
+#[tokio::test]
+async fn structured_prompt_rejects_unknown_and_unavailable_sessions() {
+    let h = spawn("naps-laptop").await;
+    let client = reqwest::Client::new();
+    let prompt = |id| {
+        client
+            .post(url(
+                h.addr,
+                &format!("/api/sessions/{id}/structured/prompt"),
+            ))
+            .json(&serde_json::json!({"prompt": "hello"}))
+    };
+
+    let unknown = prompt(Uuid::new_v4()).send().await.unwrap();
+    assert_eq!(unknown.status(), reqwest::StatusCode::NOT_FOUND);
+    let error: ApiError = unknown.json().await.unwrap();
+    assert_eq!(error.error.code, "not_found");
+
+    let terminal = h
+        .manager
+        .create(CreateSessionRequest {
+            view: SessionView::Terminal,
+            cwd: "/tmp".into(),
+            command: "sh".into(),
+            env: HashMap::new(),
+            metadata: HashMap::new(),
+            worktree: None,
+        })
+        .await
+        .unwrap();
+    let non_structured = prompt(terminal.id).send().await.unwrap();
+    assert_eq!(non_structured.status(), reqwest::StatusCode::CONFLICT);
+    let error: ApiError = non_structured.json().await.unwrap();
+    assert_eq!(error.error.code, "not_structured");
+
+    let fake = FakeAcp::new();
+    let dead = structured_session(&h, &fake).await;
+    h.manager.shutdown().await;
+    assert_eq!(h.manager.status(dead).await, Some(SessionStatus::Dead));
+    let unavailable = prompt(dead).send().await.unwrap();
+    assert_eq!(unavailable.status(), reqwest::StatusCode::CONFLICT);
+    let error: ApiError = unavailable.json().await.unwrap();
+    assert_eq!(error.error.code, "not_structured");
+}
+
+#[tokio::test]
+async fn structured_replay_honors_cursors_and_limit() {
+    let h = spawn("naps-laptop").await;
+    let fake = FakeAcp::new();
+    let id = structured_session(&h, &fake).await;
+    let client = reqwest::Client::new();
+
+    let events: Vec<serde_json::Value> = tokio::time::timeout(Duration::from_secs(2), async {
+        loop {
+            let events: Vec<serde_json::Value> = client
+                .get(url(
+                    h.addr,
+                    &format!("/api/sessions/{id}/structured/replay?since=0&limit=1"),
+                ))
+                .send()
+                .await
+                .unwrap()
+                .json()
+                .await
+                .unwrap();
+            if !events.is_empty() {
+                return events;
+            }
+            tokio::time::sleep(Duration::from_millis(10)).await;
+        }
+    })
+    .await
+    .unwrap();
+    assert_eq!(events.len(), 1);
+    assert_eq!(events[0]["cursor"], 1);
+    assert!(events[0].get("notification").is_none());
+
+    let invalid = client
+        .get(url(
+            h.addr,
+            &format!("/api/sessions/{id}/structured/replay?since=0&before=2"),
+        ))
+        .send()
+        .await
+        .unwrap();
+    assert_eq!(invalid.status(), reqwest::StatusCode::BAD_REQUEST);
+}
+
+#[tokio::test]
+async fn structured_replay_pages_projected_events_in_cursor_order() {
+    let h = spawn("naps-laptop").await;
+    let fake = FakeAcp::new();
+    let id = structured_session(&h, &fake).await;
+    let client = reqwest::Client::new();
+    unsafe { libc::kill(fake.pid() as libc::pid_t, libc::SIGUSR1) };
+    let events: Vec<serde_json::Value> = tokio::time::timeout(Duration::from_secs(2), async {
+        loop {
+            let events: Vec<serde_json::Value> = client
+                .get(url(
+                    h.addr,
+                    &format!("/api/sessions/{id}/structured/replay?before=99&limit=2"),
+                ))
+                .send()
+                .await
+                .unwrap()
+                .json()
+                .await
+                .unwrap();
+            if events.len() == 2 {
+                return events;
+            }
+            tokio::time::sleep(Duration::from_millis(10)).await;
+        }
+    })
+    .await
+    .unwrap();
+    assert_eq!(
+        events
+            .iter()
+            .map(|event| event["cursor"].as_u64().unwrap())
+            .collect::<Vec<_>>(),
+        vec![1, 2]
+    );
+    let boundary: Vec<serde_json::Value> = client
+        .get(url(
+            h.addr,
+            &format!("/api/sessions/{id}/structured/replay?before=2&limit=10"),
+        ))
+        .send()
+        .await
+        .unwrap()
+        .json()
+        .await
+        .unwrap();
+    assert_eq!(boundary.len(), 1);
+    assert_eq!(boundary[0]["cursor"], 1);
+}
+
+#[tokio::test]
+async fn structured_replay_rejects_unknown_terminal_and_dead_sessions() {
+    let h = spawn("naps-laptop").await;
+    let client = reqwest::Client::new();
+    let unknown = client
+        .get(url(
+            h.addr,
+            &format!("/api/sessions/{}/structured/replay", Uuid::new_v4()),
+        ))
+        .send()
+        .await
+        .unwrap();
+    assert_eq!(unknown.status(), reqwest::StatusCode::NOT_FOUND);
+    let terminal = h
+        .manager
+        .create(CreateSessionRequest {
+            view: SessionView::Terminal,
+            cwd: "/tmp".into(),
+            command: "sh".into(),
+            env: HashMap::new(),
+            metadata: HashMap::new(),
+            worktree: None,
+        })
+        .await
+        .unwrap();
+    let response = client
+        .get(url(
+            h.addr,
+            &format!("/api/sessions/{}/structured/replay", terminal.id),
+        ))
+        .send()
+        .await
+        .unwrap();
+    assert_eq!(response.status(), reqwest::StatusCode::CONFLICT);
+
+    let fake = FakeAcp::new();
+    let dead = structured_session(&h, &fake).await;
+    h.manager.shutdown().await;
+    assert_eq!(h.manager.status(dead).await, Some(SessionStatus::Dead));
+    let response = client
+        .get(url(
+            h.addr,
+            &format!("/api/sessions/{dead}/structured/replay"),
+        ))
+        .send()
+        .await
+        .unwrap();
+    assert_eq!(response.status(), reqwest::StatusCode::CONFLICT);
+    let error: ApiError = response.json().await.unwrap();
+    assert_eq!(error.error.code, "not_structured");
+}
+
+#[tokio::test]
+async fn structured_ws_rejects_a_dead_session() {
+    let h = spawn("naps-laptop").await;
+    let fake = FakeAcp::new();
+    let id = structured_session(&h, &fake).await;
+    h.manager.shutdown().await;
+    assert_eq!(h.manager.status(id).await, Some(SessionStatus::Dead));
+
+    let err = connect_async(ws_url(h.addr, &format!("/api/structured/{id}")))
+        .await
+        .expect_err("dead structured session must not upgrade");
+    let message = err.to_string();
+    assert!(
+        message.contains("409") || message.to_lowercase().contains("conflict"),
+        "{message}"
+    );
+}
+
 #[tokio::test]
 async fn info_returns_daemon_identity() {
     let h = spawn("naps-laptop").await;
@@ -91,6 +688,38 @@ async fn info_returns_daemon_identity() {
     assert!(resp["version"].is_string());
 }
 
+/// #159: the web client reads its leader off `/api/info` instead of a
+/// hardcoded constant, so the payload has to carry the configured one — not
+/// the default dressed up as one.
+#[tokio::test]
+async fn info_advertises_the_configured_leader() {
+    let h = spawn_with_leader(
+        "naps-laptop",
+        std::sync::Arc::new(maestro_daemon::projects::ProjectScanner::disabled()),
+        "ctrl-b",
+    )
+    .await;
+    let resp: serde_json::Value = reqwest::get(url(h.addr, "/api/info"))
+        .await
+        .unwrap()
+        .json()
+        .await
+        .unwrap();
+    assert_eq!(resp["leader"], "ctrl-b");
+}
+
+#[tokio::test]
+async fn info_reports_the_default_leader_when_unconfigured() {
+    let h = spawn("naps-laptop").await;
+    let resp: serde_json::Value = reqwest::get(url(h.addr, "/api/info"))
+        .await
+        .unwrap()
+        .json()
+        .await
+        .unwrap();
+    assert_eq!(resp["leader"], "ctrl-a");
+}
+
 #[tokio::test]
 async fn info_reports_build_and_instance() {
     // The status indicator needs a release to name and a process to compare
@@ -133,6 +762,7 @@ async fn list_sessions_starts_empty_and_reflects_creates() {
     assert!(empty.is_empty());
 
     let req = CreateSessionRequest {
+        view: Default::default(),
         cwd: "/tmp".into(),
         command: "sleep 60".into(),
         env: HashMap::new(),
@@ -349,6 +979,7 @@ async fn patch_session_renames_it() {
     let session = h
         .manager
         .create(CreateSessionRequest {
+            view: Default::default(),
             cwd: "/tmp".into(),
             command: "sleep 60".into(),
             env: HashMap::new(),
@@ -383,12 +1014,49 @@ async fn patch_unknown_session_returns_404() {
     assert_eq!(resp.status(), reqwest::StatusCode::NOT_FOUND);
 }
 
+/// #145: `POST /.../focus` with `focused: true` over HTTP stamps
+/// `last_focused_at`, observable on the next `GET /api/sessions`.
+#[tokio::test]
+async fn post_focus_stamps_last_focused_at() {
+    let h = spawn("naps-laptop").await;
+    let session = h
+        .manager
+        .create(CreateSessionRequest {
+            view: Default::default(),
+            cwd: "/tmp".into(),
+            command: "sleep 60".into(),
+            env: HashMap::new(),
+            metadata: HashMap::new(),
+            worktree: None,
+        })
+        .await
+        .unwrap();
+    assert_eq!(session.last_focused_at, None);
+
+    let resp = reqwest::Client::new()
+        .post(url(h.addr, &format!("/api/sessions/{}/focus", session.id)))
+        .json(&serde_json::json!({ "focused": true }))
+        .send()
+        .await
+        .unwrap();
+    assert_eq!(resp.status(), reqwest::StatusCode::NO_CONTENT);
+
+    let sessions: Vec<Session> = reqwest::get(url(h.addr, "/api/sessions"))
+        .await
+        .unwrap()
+        .json()
+        .await
+        .unwrap();
+    assert!(sessions[0].last_focused_at.is_some());
+}
+
 #[tokio::test]
 async fn delete_owned_session_kills_it() {
     let h = spawn("naps-laptop").await;
     let session = h
         .manager
         .create(CreateSessionRequest {
+            view: Default::default(),
             cwd: "/tmp".into(),
             command: "sleep 60".into(),
             env: HashMap::new(),
@@ -410,6 +1078,7 @@ async fn delete_owned_session_kills_it() {
 async fn spawn_via_manager(h: &Harness) -> Uuid {
     h.manager
         .create(CreateSessionRequest {
+            view: Default::default(),
             cwd: "/tmp".into(),
             command: "sleep 60".into(),
             env: HashMap::new(),
@@ -519,6 +1188,7 @@ async fn delete_a_session_whose_worktree_holds_unsaved_work_returns_409_with_the
     let session = h
         .manager
         .create(CreateSessionRequest {
+            view: Default::default(),
             cwd: repo.path().to_path_buf(),
             command: "sleep 60".into(),
             env: HashMap::new(),
@@ -571,6 +1241,7 @@ async fn delete_with_force_ends_the_session_and_keeps_the_worktree() {
     let session = h
         .manager
         .create(CreateSessionRequest {
+            view: Default::default(),
             cwd: repo.path().to_path_buf(),
             command: "sleep 60".into(),
             env: HashMap::new(),
@@ -604,6 +1275,7 @@ async fn attach_ws_streams_pty_bytes() {
     let session = h
         .manager
         .create(CreateSessionRequest {
+            view: Default::default(),
             cwd: "/tmp".into(),
             command: "bash --noprofile --norc".into(),
             env: HashMap::new(),
@@ -639,6 +1311,39 @@ async fn attach_ws_streams_pty_bytes() {
     assert!(saw_hello, "PTY did not echo through the attach WS");
 }
 
+#[tokio::test]
+async fn pty_routes_reject_structured_sessions_as_not_terminal() {
+    let h = spawn("naps-laptop").await;
+    let fake = FakeAcp::new();
+    let id = structured_session(&h, &fake).await;
+
+    let response = reqwest::Client::new()
+        .post(url(h.addr, &format!("/api/sessions/{id}/input")))
+        .json(&maestro_protocol::SendInputRequest {
+            text: "ignored".into(),
+            submit: false,
+        })
+        .send()
+        .await
+        .unwrap();
+    assert_eq!(response.status(), reqwest::StatusCode::CONFLICT);
+    let error: ApiError = response.json().await.unwrap();
+    assert_eq!(error.error.code, "not_terminal");
+    assert_eq!(error.error.message, "session is not a terminal session");
+
+    let error = connect_async(ws_url(h.addr, &format!("/api/attach/{id}")))
+        .await
+        .expect_err("structured session must not upgrade to a PTY socket");
+    let tokio_tungstenite::tungstenite::Error::Http(response) = error else {
+        panic!("expected an HTTP handshake rejection, got {error}");
+    };
+    assert_eq!(response.status(), reqwest::StatusCode::CONFLICT);
+    let body = response.body().as_deref().expect("ApiError response body");
+    let error: ApiError = serde_json::from_slice(body).unwrap();
+    assert_eq!(error.error.code, "not_terminal");
+    assert_eq!(error.error.message, "session is not a terminal session");
+}
+
 #[tokio::test]
 async fn attach_ws_for_unknown_session_returns_404() {
     let h = spawn("naps-laptop").await;
@@ -672,6 +1377,7 @@ async fn events_ws_sends_a_snapshot_then_streams_deltas() {
     let created = h
         .manager
         .create(CreateSessionRequest {
+            view: Default::default(),
             cwd: cwd.path().to_path_buf(),
             command: "sleep 30".into(),
             env: HashMap::new(),
@@ -704,6 +1410,73 @@ async fn events_ws_sends_a_snapshot_then_streams_deltas() {
     }
 }
 
+#[tokio::test]
+async fn events_ws_streams_structured_activity_without_hook_overrides() {
+    let h = spawn("konishi").await;
+    let fake = FakeAcp::new();
+    let mut env = fake.env();
+    env.insert("FAKE_ACP_DELAY_PROMPT_MS".into(), "500".into());
+    let (mut ws, _) = connect_async(ws_url(h.addr, "/api/events"))
+        .await
+        .expect("events ws");
+    assert!(matches!(
+        next_event(&mut ws).await,
+        maestro_protocol::CatalogEvent::Snapshot { .. }
+    ));
+
+    let id = structured_session_with_env(&h, env).await;
+    let maestro_protocol::CatalogEvent::SessionAdded { session } = next_event(&mut ws).await else {
+        panic!("expected structured SessionAdded")
+    };
+    assert_eq!(session.activity, ActivityState::Idle);
+
+    let client = reqwest::Client::new();
+    let prompt = client
+        .post(url(
+            h.addr,
+            &format!("/api/sessions/{id}/structured/prompt"),
+        ))
+        .json(&serde_json::json!({"prompt": "hello"}))
+        .send()
+        .await
+        .unwrap();
+    assert_eq!(prompt.status(), reqwest::StatusCode::NO_CONTENT);
+    let report = client
+        .post(url(h.addr, &format!("/api/sessions/{id}/activity")))
+        .json(&serde_json::json!({"state": "Error"}))
+        .send()
+        .await
+        .unwrap();
+    assert_eq!(report.status(), reqwest::StatusCode::NO_CONTENT);
+    wait_for_session_activity(&h, id, ActivityState::Active).await;
+
+    let mut activities = Vec::new();
+    tokio::time::timeout(Duration::from_secs(2), async {
+        loop {
+            if let maestro_protocol::CatalogEvent::SessionUpdated { session } =
+                next_event(&mut ws).await
+            {
+                activities.push(session.activity);
+                if session.activity == ActivityState::Idle {
+                    return;
+                }
+            }
+        }
+    })
+    .await
+    .expect("structured turn returns to idle");
+    assert!(
+        activities.contains(&ActivityState::Active),
+        "{activities:?}"
+    );
+    assert!(
+        !activities.contains(&ActivityState::Error),
+        "{activities:?}"
+    );
+
+    h.manager.kill(id, false).await.unwrap();
+}
+
 /// Each subscriber has its own lag domain now that the publisher task is gone:
 /// two clients connected at different times both get their own Snapshot.
 #[tokio::test]
@@ -716,6 +1489,7 @@ async fn every_events_subscriber_gets_its_own_snapshot() {
 
     h.manager
         .create(CreateSessionRequest {
+            view: Default::default(),
             cwd: cwd.path().to_path_buf(),
             command: "sleep 30".into(),
             env: HashMap::new(),

crates/maestro-daemon/tests/rename.rs

@@ -51,6 +51,7 @@ async fn spawn_named(manager: &SessionManager, name: Option<&str>) -> Uuid {
     };
     manager
         .create(CreateSessionRequest {
+            view: Default::default(),
             cwd: "/tmp".into(),
             command: "sleep 60".into(),
             env: Default::default(),

crates/maestro-daemon/tests/session_decisions.rs

@@ -64,6 +64,7 @@ impl Fx {
 
     fn request(&self, command: &str) -> CreateSessionRequest {
         CreateSessionRequest {
+            view: Default::default(),
             cwd: self.tmp.path().to_path_buf(),
             command: command.into(),
             env: HashMap::new(),
@@ -555,3 +556,63 @@ async fn spawn_overrides_client_supplied_maestro_variables() {
         Some(&"http://127.0.0.1:7070".to_string())
     );
 }
+
+/// Two clients attached to one session used to resize the shared window past
+/// each other on every report they made. Every flip repaints a full-screen
+/// agent at a new height and orphans the rows it drew at the old one, which
+/// reads to the operator as a pane that has stopped taking input.
+#[tokio::test]
+async fn clients_of_different_sizes_do_not_resize_the_window_past_each_other() {
+    let fx = Fx::new();
+    let s = fx.manager.create(fx.request("bash")).await.expect("create");
+    let web = fx.manager.attach_viewport();
+    let tui = fx.manager.attach_viewport();
+
+    fx.manager.set_viewport(s.id, web, 53, 46).await.unwrap();
+    fx.manager.set_viewport(s.id, tui, 53, 20).await.unwrap();
+    // Both keep reporting, as a browser's ResizeObserver and the TUI's own
+    // redraw loop do. Neither report changes the arbitrated size.
+    for _ in 0..5 {
+        fx.manager.set_viewport(s.id, web, 53, 46).await.unwrap();
+        fx.manager.set_viewport(s.id, tui, 53, 20).await.unwrap();
+    }
+
+    let resizes: Vec<_> = fx
+        .fake
+        .calls()
+        .into_iter()
+        .filter_map(|c| match c {
+            Call::ResizeWindow { cols, rows, .. } => Some((cols, rows)),
+            _ => None,
+        })
+        .collect();
+    assert_eq!(
+        resizes,
+        vec![(53, 46), (53, 20)],
+        "the window was resized more than the arbitrated size actually changed"
+    );
+}
+
+/// The smaller client leaving hands the window back to the one still attached.
+#[tokio::test]
+async fn releasing_a_client_resizes_to_what_is_left() {
+    let fx = Fx::new();
+    let s = fx.manager.create(fx.request("bash")).await.expect("create");
+    let web = fx.manager.attach_viewport();
+    let tui = fx.manager.attach_viewport();
+    fx.manager.set_viewport(s.id, web, 80, 46).await.unwrap();
+    fx.manager.set_viewport(s.id, tui, 80, 20).await.unwrap();
+
+    fx.manager.release_viewport(s.id, tui).await;
+
+    let resizes: Vec<_> = fx
+        .fake
+        .calls()
+        .into_iter()
+        .filter_map(|c| match c {
+            Call::ResizeWindow { cols, rows, .. } => Some((cols, rows)),
+            _ => None,
+        })
+        .collect();
+    assert_eq!(resizes, vec![(80, 46), (80, 20), (80, 46)]);
+}

crates/maestro-daemon/tests/session_manager.rs

@@ -22,6 +22,7 @@ async fn create_then_kill_round_trip() {
     let session = fx
         .manager
         .create(CreateSessionRequest {
+            view: Default::default(),
             cwd: cwd.path().to_path_buf(),
             command: "sleep 30".into(),
             env: HashMap::new(),
@@ -63,6 +64,7 @@ async fn create_appends_to_spawn_history() {
     let session = fx
         .manager
         .create(CreateSessionRequest {
+            view: Default::default(),
             cwd: cwd.path().to_path_buf(),
             command: "sleep 30".into(),
             env: HashMap::new(),
@@ -92,6 +94,7 @@ async fn create_without_history_logs_nothing() {
     let cwd = TempDir::new().unwrap();
     fx.manager
         .create(CreateSessionRequest {
+            view: Default::default(),
             cwd: cwd.path().to_path_buf(),
             command: "sleep 30".into(),
             env: HashMap::new(),
@@ -114,6 +117,7 @@ async fn recover_adopts_existing_tmux_sessions() {
     let s = fx
         .manager
         .create(CreateSessionRequest {
+            view: Default::default(),
             cwd: cwd.path().to_path_buf(),
             command: "sleep 30".into(),
             env: HashMap::new(),
@@ -153,6 +157,7 @@ async fn create_captures_initial_output_in_replay_buffer() {
     let s = fx
         .manager
         .create(CreateSessionRequest {
+            view: Default::default(),
             cwd: cwd.path().to_path_buf(),
             // The shell prints the marker before doing anything else and
             // then sleeps so the session stays alive. Before NAP-253 this
@@ -200,6 +205,7 @@ async fn attach_replay_is_the_current_screen_not_the_byte_tail() {
     let s = fx
         .manager
         .create(CreateSessionRequest {
+        view: Default::default(),
             cwd: cwd.path().to_path_buf(),
             // Print a line, then switch to the alternate screen the way a
             // full-screen program does on startup. Only the second marker is
@@ -258,6 +264,7 @@ async fn attach_replay_carries_the_panes_mouse_modes() {
     let s = fx
         .manager
         .create(CreateSessionRequest {
+        view: Default::default(),
             cwd: cwd.path().to_path_buf(),
             // Alternate screen, then button-event tracking (?1002) with SGR
             // coordinates (?1006) — what tmux and agent TUIs actually request.
@@ -311,6 +318,7 @@ async fn recover_re_pipes_pane_so_output_reaches_subscribers() {
     let s = fx
         .manager
         .create(CreateSessionRequest {
+            view: Default::default(),
             cwd: cwd.path().to_path_buf(),
             command: "bash --noprofile --norc".into(),
             env: HashMap::new(),
@@ -373,6 +381,7 @@ async fn pty_broadcast_delivers_bytes_to_subscribers() {
     let s = fx
         .manager
         .create(CreateSessionRequest {
+            view: Default::default(),
             cwd: cwd.path().to_path_buf(),
             command: "bash --noprofile --norc".into(),
             env: HashMap::new(),
@@ -423,6 +432,7 @@ async fn liveness_watcher_marks_dead_sessions_and_keeps_them_until_dismissed() {
     let s = fx
         .manager
         .create(CreateSessionRequest {
+            view: Default::default(),
             cwd: cwd.path().to_path_buf(),
             command: "sleep 30".into(),
             env: HashMap::new(),
@@ -488,6 +498,7 @@ async fn watcher_refreshes_the_blocked_work_indicator() {
 
     fx.manager
         .create(CreateSessionRequest {
+            view: Default::default(),
             cwd: repo.path().to_path_buf(),
             command: "sleep 30".into(),
             env: HashMap::new(),
@@ -580,6 +591,7 @@ async fn kill_removes_worktree_even_when_spec_says_keep() {
     let s = fx
         .manager
         .create(CreateSessionRequest {
+            view: Default::default(),
             cwd: repo.path().to_path_buf(),
             command: "sleep 30".into(),
             env: HashMap::new(),
@@ -617,6 +629,7 @@ async fn killing_refuses_a_worktree_with_unsaved_work_and_keeps_the_session() {
     let s = fx
         .manager
         .create(CreateSessionRequest {
+            view: Default::default(),
             cwd: repo.path().to_path_buf(),
             command: "sleep 30".into(),
             env: HashMap::new(),
@@ -680,6 +693,7 @@ async fn killing_refuses_until_the_branch_is_pushed() {
     let s = fx
         .manager
         .create(CreateSessionRequest {
+            view: Default::default(),
             cwd: repo.path().to_path_buf(),
             command: "sleep 30".into(),
             env: HashMap::new(),
@@ -729,6 +743,7 @@ async fn force_killing_a_guarded_worktree_leaves_it_on_disk() {
     let s = fx
         .manager
         .create(CreateSessionRequest {
+            view: Default::default(),
             cwd: repo.path().to_path_buf(),
             command: "sleep 30".into(),
             env: HashMap::new(),
@@ -774,6 +789,7 @@ async fn force_on_a_clear_worktree_removes_it_as_usual() {
     let s = fx
         .manager
         .create(CreateSessionRequest {
+            view: Default::default(),
             cwd: repo.path().to_path_buf(),
             command: "sleep 30".into(),
             env: HashMap::new(),
@@ -814,6 +830,7 @@ async fn killing_an_ignored_only_worktree_succeeds() {
     let s = fx
         .manager
         .create(CreateSessionRequest {
+            view: Default::default(),
             cwd: repo.path().to_path_buf(),
             command: "sleep 30".into(),
             env: HashMap::new(),
@@ -855,6 +872,7 @@ async fn natural_exit_of_a_guarded_worktree_leaves_it_on_disk() {
     let s = fx
         .manager
         .create(CreateSessionRequest {
+            view: Default::default(),
             cwd: repo.path().to_path_buf(),
             command: "sleep 30".into(),
             env: HashMap::new(),
@@ -916,6 +934,7 @@ async fn natural_exit_of_a_pristine_worktree_removes_it() {
     let s = fx
         .manager
         .create(CreateSessionRequest {
+            view: Default::default(),
             cwd: repo.path().to_path_buf(),
             command: "sleep 30".into(),
             env: HashMap::new(),
@@ -976,6 +995,7 @@ async fn liveness_watcher_leaves_running_sessions_alone() {
     let s = fx
         .manager
         .create(CreateSessionRequest {
+            view: Default::default(),
             cwd: cwd.path().to_path_buf(),
             command: "sleep 30".into(),
             env: HashMap::new(),
@@ -1010,6 +1030,7 @@ async fn worktree_base_repo_records_the_main_checkout_not_the_request() {
     let first = fx
         .manager
         .create(CreateSessionRequest {
+            view: Default::default(),
             cwd: repo.path().to_path_buf(),
             command: "sleep 30".into(),
             env: HashMap::new(),
@@ -1027,6 +1048,7 @@ async fn worktree_base_repo_records_the_main_checkout_not_the_request() {
     let second = fx
         .manager
         .create(CreateSessionRequest {
+            view: Default::default(),
             cwd: inner_worktree.clone(),
             command: "sleep 30".into(),
             env: HashMap::new(),
@@ -1065,6 +1087,7 @@ async fn spawned_sessions_export_maestro_session_id_and_url() {
     let s = fx
         .manager
         .create(CreateSessionRequest {
+            view: Default::default(),
             cwd: cwd.path().to_path_buf(),
             command: "sleep 30".into(),
             env: HashMap::new(),
@@ -1091,3 +1114,112 @@ async fn spawned_sessions_export_maestro_session_id_and_url() {
 
     fx.manager.kill(s.id, false).await.expect("kill");
 }
+
+/// docs/COMMAND-BAR.md, empty-query ordering: a session that has never been
+/// focused carries no `last_focused_at` at all, which is what lets a client
+/// sort it after every session that has one (#145).
+#[tokio::test]
+async fn a_freshly_created_session_has_never_been_focused() {
+    let fx = DaemonFixture::new();
+    let cwd = TempDir::new().unwrap();
+
+    let s = fx
+        .manager
+        .create(CreateSessionRequest {
+            view: Default::default(),
+            cwd: cwd.path().to_path_buf(),
+            command: "sleep 30".into(),
+            env: HashMap::new(),
+            metadata: HashMap::new(),
+            worktree: None,
+        })
+        .await
+        .expect("create");
+
+    assert_eq!(s.last_focused_at, None);
+    assert_eq!(fx.manager.snapshot().await[0].last_focused_at, None);
+}
+
+/// #145: `POST /.../focus` reporting `focused: true` stamps
+/// `last_focused_at` and announces it on the event stream; reporting
+/// `focused: false` (losing focus) leaves the stamp alone, since the bar
+/// orders by when the operator last arrived, not when they left.
+#[tokio::test]
+async fn set_focused_true_stamps_last_focused_at() {
+    let fx = DaemonFixture::new();
+    let cwd = TempDir::new().unwrap();
+
+    let s = fx
+        .manager
+        .create(CreateSessionRequest {
+            view: Default::default(),
+            cwd: cwd.path().to_path_buf(),
+            command: "sleep 30".into(),
+            env: HashMap::new(),
+            metadata: HashMap::new(),
+            worktree: None,
+        })
+        .await
+        .expect("create");
+
+    let mut events = fx.manager.events();
+    let before = chrono::Utc::now();
+    fx.manager.set_focused(s.id, true).await.expect("focus");
+
+    let updated = fx.manager.snapshot().await[0].clone();
+    let stamp = updated.last_focused_at.expect("stamped on focus");
+    assert!(stamp >= before);
+
+    let mut saw_update = false;
+    while let Ok(event) = tokio::time::timeout(Duration::from_millis(200), events.recv()).await {
+        if let Ok(CatalogEvent::SessionUpdated { session }) = event {
+            if session.id == s.id && session.last_focused_at == Some(stamp) {
+                saw_update = true;
+                break;
+            }
+        }
+    }
+    assert!(saw_update, "expected a SessionUpdated carrying the stamp");
+
+    fx.manager.set_focused(s.id, false).await.expect("unfocus");
+    let after_unfocus = fx.manager.snapshot().await[0].clone();
+    assert_eq!(
+        after_unfocus.last_focused_at,
+        Some(stamp),
+        "losing focus must not clear the last-focused stamp"
+    );
+}
+
+/// #145: opening `/api/attach/:id` is focusing too — it must stamp the same
+/// field `set_focused` does, so a client that only ever attaches sorts
+/// identically to one that reports focus explicitly.
+#[tokio::test]
+async fn attaching_stamps_last_focused_at() {
+    let fx = DaemonFixture::new();
+    let cwd = TempDir::new().unwrap();
+
+    let s = fx
+        .manager
+        .create(CreateSessionRequest {
+            view: Default::default(),
+            cwd: cwd.path().to_path_buf(),
+            command: "sleep 30".into(),
+            env: HashMap::new(),
+            metadata: HashMap::new(),
+            worktree: None,
+        })
+        .await
+        .expect("create");
+    assert_eq!(s.last_focused_at, None);
+
+    let before = chrono::Utc::now();
+    let (_replay, _rx) = fx
+        .manager
+        .subscribe_pty_with_replay(s.id)
+        .await
+        .expect("known session");
+
+    let updated = fx.manager.snapshot().await[0].clone();
+    let stamp = updated.last_focused_at.expect("attach stamps focus");
+    assert!(stamp >= before);
+}

crates/maestro-daemon/tests/sidecar.rs

@@ -6,8 +6,8 @@ use std::collections::HashMap;
 use std::path::PathBuf;
 
 use chrono::{DateTime, Utc};
-use maestro_daemon::sidecar::SidecarStore;
-use maestro_protocol::{Session, SessionStatus};
+use maestro_daemon::sidecar::{PersistedEvent, SidecarStore};
+use maestro_protocol::{Session, SessionStatus, SessionView, TranscriptRow, TranscriptRowKind};
 use serde_json::Value;
 use tempfile::TempDir;
 use uuid::Uuid;
@@ -31,6 +31,9 @@ fn sample(id: Uuid) -> Session {
         activity_since: chrono::Utc::now(),
         current_cwd: Some(PathBuf::from("/tmp/work/crates")),
         blocked_work: None,
+        last_focused_at: None,
+        acp_session_id: None,
+        view: SessionView::Terminal,
     }
 }
 
@@ -65,15 +68,30 @@ fn delete_removes_file_and_is_idempotent() {
     let s = sample(id);
 
     store.write(&s).unwrap();
+    store.mark_for_recovery(id).unwrap();
     assert!(store.path_for(id).exists());
+    assert!(store.recovery_path_for(id).exists());
 
     store.delete(id).unwrap();
     assert!(!store.path_for(id).exists());
+    assert!(!store.recovery_path_for(id).exists());
 
     // second delete is a no-op
     store.delete(id).unwrap();
 }
 
+#[test]
+fn recovery_marker_is_consumed_once() {
+    let dir = TempDir::new().unwrap();
+    let store = SidecarStore::new(dir.path());
+    let id = Uuid::new_v4();
+
+    assert!(!store.take_recovery_marker(id).unwrap());
+    store.mark_for_recovery(id).unwrap();
+    assert!(store.take_recovery_marker(id).unwrap());
+    assert!(!store.take_recovery_marker(id).unwrap());
+}
+
 #[test]
 fn load_all_recovers_every_sidecar_and_skips_garbage() {
     let dir = TempDir::new().unwrap();
@@ -102,6 +120,37 @@ fn load_all_returns_empty_when_directory_missing() {
     assert!(store.load_all().unwrap().is_empty());
 }
 
+#[test]
+fn sidecar_missing_view_key_reads_as_terminal() {
+    // A pre-#133 sidecar on disk has no `view` field at all.
+    let dir = TempDir::new().unwrap();
+    let store = SidecarStore::new(dir.path());
+    let id = Uuid::new_v4();
+
+    let mut value = serde_json::to_value(sample(id)).unwrap();
+    value.as_object_mut().unwrap().remove("view");
+    std::fs::write(store.path_for(id), serde_json::to_vec(&value).unwrap()).unwrap();
+
+    let loaded = store.read(id).expect("read").expect("present");
+    assert_eq!(loaded.view, SessionView::Terminal);
+}
+
+#[test]
+fn sidecar_structured_view_round_trips() {
+    let dir = TempDir::new().unwrap();
+    let store = SidecarStore::new(dir.path());
+    let id = Uuid::new_v4();
+    let mut s = sample(id);
+    s.view = SessionView::Structured;
+
+    store.write(&s).expect("write");
+    let loaded = store.read(id).expect("read");
+    assert_eq!(
+        loaded.as_ref().map(|s| s.view),
+        Some(SessionView::Structured)
+    );
+}
+
 #[test]
 fn write_creates_parent_directory() {
     let dir = TempDir::new().unwrap();
@@ -112,3 +161,237 @@ fn write_creates_parent_directory() {
     assert!(nested.exists());
     assert!(store.path_for(s.id).exists());
 }
+
+// ---- per-session event log (#135) ----
+
+use maestro_acp::schema::{ContentBlock, SessionNotification, SessionUpdate, TextContent};
+use maestro_daemon::sidecar::EventCursor;
+
+fn note(text: &str) -> SessionNotification {
+    SessionNotification::new(
+        "acp-1",
+        SessionUpdate::AgentMessageChunk(maestro_acp::schema::ContentChunk::new(
+            ContentBlock::Text(TextContent::new(text)),
+        )),
+    )
+}
+
+fn text_of(n: &SessionNotification) -> &str {
+    match &n.update {
+        SessionUpdate::AgentMessageChunk(chunk) => match &chunk.content {
+            ContentBlock::Text(t) => &t.text,
+            other => panic!("unexpected content {other:?}"),
+        },
+        other => panic!("unexpected update {other:?}"),
+    }
+}
+
+fn event_text(event: &maestro_daemon::sidecar::LoggedEvent) -> &str {
+    let maestro_daemon::sidecar::PersistedEvent::Notification(notification) = &event.event else {
+        panic!("expected ACP notification")
+    };
+    text_of(notification)
+}
+
+#[test]
+fn append_assigns_line_position_as_seq_and_reads_back() {
+    let dir = TempDir::new().unwrap();
+    let store = SidecarStore::new(dir.path());
+    let id = Uuid::new_v4();
+
+    let mut log = store.open_events(id).expect("open");
+    assert_eq!(log.last_seq(), 0);
+    assert_eq!(log.append(note("a")).unwrap(), 1);
+    assert_eq!(log.append(note("b")).unwrap(), 2);
+    assert_eq!(log.append(note("c")).unwrap(), 3);
+    assert_eq!(log.last_seq(), 3);
+
+    let path = store.events_path_for(id);
+    assert!(path.ends_with(format!("{id}.events.jsonl")), "{path:?}");
+    let raw = std::fs::read_to_string(&path).unwrap();
+    assert_eq!(raw.lines().count(), 3, "one object per line:\n{raw}");
+    for line in raw.lines() {
+        let v: Value = serde_json::from_str(line).expect("each line is one JSON object");
+        assert_eq!(v["sessionId"], "acp-1");
+    }
+
+    let all = store.read_events(id, EventCursor::Since(0), 100).unwrap();
+    assert_eq!(all.iter().map(|e| e.seq).collect::<Vec<_>>(), vec![1, 2, 3]);
+    assert_eq!(
+        all.iter().map(event_text).collect::<Vec<_>>(),
+        vec!["a", "b", "c"]
+    );
+}
+
+#[test]
+fn since_reads_forward_and_before_reads_backward_with_limit() {
+    let dir = TempDir::new().unwrap();
+    let store = SidecarStore::new(dir.path());
+    let id = Uuid::new_v4();
+    let mut log = store.open_events(id).unwrap();
+    for i in 1..=6 {
+        log.append(note(&format!("n{i}"))).unwrap();
+    }
+
+    // `since` is exclusive: what a client that already holds seq 2 needs.
+    let fwd = store.read_events(id, EventCursor::Since(2), 3).unwrap();
+    assert_eq!(fwd.iter().map(|e| e.seq).collect::<Vec<_>>(), vec![3, 4, 5]);
+    // Past the end: nothing, not an error.
+    assert!(store
+        .read_events(id, EventCursor::Since(6), 3)
+        .unwrap()
+        .is_empty());
+
+    // `before` is exclusive and pages backward: the `limit` events closest
+    // to the cursor, still in ascending seq order.
+    let back = store
+        .read_events(id, EventCursor::Before(Some(5)), 2)
+        .unwrap();
+    assert_eq!(back.iter().map(|e| e.seq).collect::<Vec<_>>(), vec![3, 4]);
+    // No cursor: the tail of the log, for a first paint.
+    let tail = store.read_events(id, EventCursor::Before(None), 2).unwrap();
+    assert_eq!(tail.iter().map(|e| e.seq).collect::<Vec<_>>(), vec![5, 6]);
+    // Paging past the start runs out cleanly.
+    let start = store
+        .read_events(id, EventCursor::Before(Some(2)), 10)
+        .unwrap();
+    assert_eq!(start.iter().map(|e| e.seq).collect::<Vec<_>>(), vec![1]);
+    assert!(store
+        .read_events(id, EventCursor::Before(Some(1)), 10)
+        .unwrap()
+        .is_empty());
+}
+
+#[test]
+fn missing_log_reads_as_empty() {
+    let dir = TempDir::new().unwrap();
+    let store = SidecarStore::new(dir.path());
+    let id = Uuid::new_v4();
+    assert!(store
+        .read_events(id, EventCursor::Since(0), 10)
+        .unwrap()
+        .is_empty());
+    assert!(store
+        .read_events(id, EventCursor::Before(None), 10)
+        .unwrap()
+        .is_empty());
+}
+
+#[test]
+fn malformed_lines_are_skipped_but_keep_their_seq() {
+    let dir = TempDir::new().unwrap();
+    let store = SidecarStore::new(dir.path());
+    let id = Uuid::new_v4();
+    let mut log = store.open_events(id).unwrap();
+    log.append(note("first")).unwrap();
+    drop(log);
+
+    // Garbage in the middle and a line that is JSON but not a notification.
+    let path = store.events_path_for(id);
+    let mut raw = std::fs::read_to_string(&path).unwrap();
+    raw.push_str("{not json\n");
+    raw.push_str("{\"unrelated\": true}\n");
+    std::fs::write(&path, raw).unwrap();
+    let mut log = store.open_events(id).unwrap();
+    assert_eq!(log.last_seq(), 3);
+    assert_eq!(log.append(note("fourth")).unwrap(), 4);
+
+    let all = store.read_events(id, EventCursor::Since(0), 10).unwrap();
+    assert_eq!(all.iter().map(|e| e.seq).collect::<Vec<_>>(), vec![1, 4]);
+    assert_eq!(event_text(&all[1]), "fourth");
+}
+
+#[test]
+fn truncated_last_line_still_opens_and_the_next_append_starts_a_fresh_line() {
+    // A hard kill mid-write leaves a partial line with no newline.
+    let dir = TempDir::new().unwrap();
+    let store = SidecarStore::new(dir.path());
+    let id = Uuid::new_v4();
+    let mut log = store.open_events(id).unwrap();
+    log.append(note("whole")).unwrap();
+    drop(log);
+
+    let path = store.events_path_for(id);
+    let mut raw = std::fs::read(&path).unwrap();
+    raw.extend_from_slice(br#"{"sessionId":"acp-1","update":{"sessionUpd"#);
+    std::fs::write(&path, &raw).unwrap();
+
+    // Reads: the partial line is skipped, nothing else is lost.
+    let all = store.read_events(id, EventCursor::Since(0), 10).unwrap();
+    assert_eq!(all.iter().map(|e| e.seq).collect::<Vec<_>>(), vec![1]);
+
+    // Reopening terminates the partial line so the next append does not
+    // glue onto it; the partial keeps a seq of its own.
+    let mut log = store.open_events(id).unwrap();
+    assert_eq!(log.last_seq(), 2);
+    assert_eq!(log.append(note("after")).unwrap(), 3);
+    let all = store.read_events(id, EventCursor::Since(0), 10).unwrap();
+    assert_eq!(all.iter().map(|e| e.seq).collect::<Vec<_>>(), vec![1, 3]);
+    assert_eq!(event_text(&all[1]), "after");
+    let raw = std::fs::read_to_string(&path).unwrap();
+    assert_eq!(raw.lines().count(), 3, "{raw}");
+}
+
+#[test]
+fn delete_removes_the_event_log_and_load_all_ignores_it() {
+    let dir = TempDir::new().unwrap();
+    let store = SidecarStore::new(dir.path());
+    let id = Uuid::new_v4();
+    store.write(&sample(id)).unwrap();
+    let mut log = store.open_events(id).unwrap();
+    log.append(note("x")).unwrap();
+    drop(log);
+    let legacy_approvals = dir.path().join(format!("{id}.approvals.jsonl"));
+    std::fs::write(&legacy_approvals, b"obsolete").unwrap();
+    assert!(store.events_path_for(id).exists());
+
+    let loaded = store.load_all().unwrap();
+    assert_eq!(loaded.len(), 1, "the .jsonl must not be read as a sidecar");
+
+    store.delete(id).unwrap();
+    assert!(!store.path_for(id).exists());
+    assert!(!store.events_path_for(id).exists());
+    assert!(!legacy_approvals.exists());
+    // Idempotent with the log already gone.
+    store.delete(id).unwrap();
+}
+
+#[test]
+fn approval_rows_share_event_cursors_with_legacy_acp_lines() {
+    let dir = TempDir::new().unwrap();
+    let store = SidecarStore::new(dir.path());
+    let id = Uuid::new_v4();
+    let legacy = serde_json::to_vec(&note("before")).unwrap();
+    std::fs::create_dir_all(dir.path()).unwrap();
+    std::fs::write(store.events_path_for(id), [legacy, b"\n".to_vec()].concat()).unwrap();
+
+    let mut log = store.open_events(id).unwrap();
+    assert_eq!(
+        log.append(PersistedEvent::Approval {
+            row: TranscriptRow {
+                id: "approval:secret".into(),
+                kind: TranscriptRowKind::Approval,
+                data: serde_json::json!({"tool": "bash"}),
+            },
+        })
+        .unwrap(),
+        2
+    );
+    assert_eq!(log.append(note("after")).unwrap(), 3);
+
+    let all = store.read_events(id, EventCursor::Since(0), 10).unwrap();
+    assert_eq!(
+        all.iter().map(|event| event.seq).collect::<Vec<_>>(),
+        [1, 2, 3]
+    );
+    assert!(matches!(all[1].event, PersistedEvent::Approval { .. }));
+    assert_eq!(event_text(&all[0]), "before");
+    assert_eq!(event_text(&all[2]), "after");
+
+    let since = store.read_events(id, EventCursor::Since(1), 1).unwrap();
+    assert_eq!(since[0].seq, 2);
+    let before = store
+        .read_events(id, EventCursor::Before(Some(3)), 1)
+        .unwrap();
+    assert_eq!(before[0].seq, 2);
+}

crates/maestro-daemon/tests/web_ui.rs

@@ -26,6 +26,7 @@ async fn spawn() -> Harness {
         "/home/test",
         maestro_config::SpawnSection::default().resolve().unwrap(),
         std::sync::Arc::new(maestro_daemon::projects::ProjectScanner::disabled()),
+        maestro_config::DEFAULT_LEADER,
     ));
     let listener = TcpListener::bind(SocketAddr::from((Ipv4Addr::LOCALHOST, 0)))
         .await

crates/maestro-daemon/tests/worktree.rs

@@ -405,8 +405,10 @@ fn run_git(dir: &std::path::Path, args: &[&str]) {
     );
 }
 
+/// 49ab7e9: a new-branch add onto a name that already exists suffixes the
+/// branch (and so the directory) instead of failing, per docs/WORKTREES.md.
 #[test]
-fn add_fails_when_branch_already_exists() {
+fn add_new_suffixes_when_branch_already_exists() {
     let repo_dir = TempDir::new().unwrap();
     let repo = repo_dir.path().to_path_buf();
     init_repo(&repo);
@@ -423,9 +425,9 @@ fn add_fails_when_branch_already_exists() {
     let wt_root = TempDir::new().unwrap();
     let mgr = WorktreeManager::new(Some(wt_root.path().to_path_buf()));
 
-    let err = mgr.add_new(&repo, "feat/dup").unwrap_err();
-    let msg = format!("{err}");
-    assert!(msg.contains("git exited"), "{msg}");
+    let path = mgr.add_new(&repo, "feat/dup").unwrap();
+    assert!(path.ends_with("feat/dup-2"), "{}", path.display());
+    assert!(path.is_dir());
 }
 
 /// The project picker lists linked worktrees as pickable rows, so `base_repo`

crates/maestro-e2e/Cargo.toml

@@ -13,6 +13,7 @@ path = "src/lib.rs"
 [dependencies]
 chrono.workspace = true
 futures-util.workspace = true
+libc.workspace = true
 maestro-protocol = { workspace = true, features = ["client"] }
 maestro-testing.workspace = true
 serde.workspace = true

crates/maestro-e2e/src/daemon.rs

@@ -87,6 +87,14 @@ impl Daemon {
         }
     }
 
+    /// Send the daemon the same SIGTERM systemd uses, without waiting for its
+    /// graceful HTTP shutdown to finish.
+    pub fn send_sigterm(&self) {
+        let child = self.child.as_ref().expect("daemon is running");
+        let result = unsafe { libc::kill(child.id() as libc::pid_t, libc::SIGTERM) };
+        assert_eq!(result, 0, "send SIGTERM to daemon");
+    }
+
     /// Re-spawn the daemon on the same port + state. The previous tmux
     /// server (under `TMUX_TMPDIR`) is left running so `recover()` can adopt
     /// its sessions.

crates/maestro-e2e/tests/e2e.rs

@@ -15,7 +15,7 @@ use std::time::{Duration, Instant};
 use futures_util::{SinkExt, StreamExt};
 use maestro_e2e::util::wait_for_async;
 use maestro_e2e::{Daemon, TestClient};
-use maestro_protocol::{CreateSessionRequest, WorktreeSpec};
+use maestro_protocol::{CreateSessionRequest, SessionStatus, SessionView, WorktreeSpec};
 use tempfile::TempDir;
 use tokio_tungstenite::tungstenite::Message as WsMessage;
 
@@ -27,6 +27,7 @@ async fn bring_up() -> (Daemon, TestClient) {
 
 fn create_req(cwd: &std::path::Path, command: &str) -> CreateSessionRequest {
     CreateSessionRequest {
+        view: Default::default(),
         cwd: cwd.to_path_buf(),
         command: command.into(),
         env: HashMap::new(),
@@ -35,6 +36,61 @@ fn create_req(cwd: &std::path::Path, command: &str) -> CreateSessionRequest {
     }
 }
 
+struct FakeAcp {
+    _dir: TempDir,
+    env: HashMap<String, String>,
+}
+
+fn fake_acp(log: &std::path::Path) -> FakeAcp {
+    let dir = tempfile::tempdir().expect("fake adapter dir");
+    let adapter = dir.path().join("claude-code-acp");
+    std::fs::copy(
+        concat!(
+            env!("CARGO_MANIFEST_DIR"),
+            "/../maestro-acp/tests/fake_acp_agent.py"
+        ),
+        &adapter,
+    )
+    .expect("copy fake adapter");
+    let mut permissions = std::fs::metadata(&adapter)
+        .expect("adapter metadata")
+        .permissions();
+    #[cfg(unix)]
+    {
+        use std::os::unix::fs::PermissionsExt;
+        permissions.set_mode(0o755);
+    }
+    std::fs::set_permissions(&adapter, permissions).expect("make fake adapter executable");
+    let env = HashMap::from([
+        (
+            "PATH".into(),
+            format!(
+                "{}:{}",
+                dir.path().display(),
+                std::env::var("PATH").unwrap_or_default()
+            ),
+        ),
+        ("FAKE_ACP_LOG".into(), log.to_string_lossy().into_owned()),
+    ]);
+    FakeAcp { _dir: dir, env }
+}
+
+fn fake_acp_pid(log: &std::path::Path) -> Option<u32> {
+    std::fs::read_to_string(log).ok()?.lines().find_map(|line| {
+        line.strip_prefix("start pid=")?
+            .split(' ')
+            .next()?
+            .parse()
+            .ok()
+    })
+}
+
+fn pid_alive(pid: u32) -> bool {
+    std::fs::read_to_string(format!("/proc/{pid}/stat"))
+        .map(|stat| !stat.contains(") Z "))
+        .unwrap_or(false)
+}
+
 /// A worktree spec built through its wire shape. The daemon and clients ship
 /// together (#87 dropped `cleanup_on_kill` from the struct), so the JSON
 /// object carries only the fields the lifecycle actually honours.
@@ -49,6 +105,7 @@ fn worktree_spec(base_repo: &std::path::Path, branch: &str, create_branch: bool)
 /// Spawn request carrying a worktree spec against `base`.
 fn worktree_req(base: &std::path::Path, branch: &str, create_branch: bool) -> CreateSessionRequest {
     CreateSessionRequest {
+        view: Default::default(),
         cwd: base.to_path_buf(),
         command: "sleep 30".into(),
         env: HashMap::new(),
@@ -143,6 +200,7 @@ async fn kill_removes_clean_worktree() {
     init_repo(base.path());
 
     let req = CreateSessionRequest {
+        view: Default::default(),
         cwd: base.path().to_path_buf(),
         command: "sleep 30".into(),
         env: HashMap::new(),
@@ -196,6 +254,7 @@ async fn kill_refuses_worktree_with_uncommitted_changes() {
         .join("unsaved");
 
     let req = CreateSessionRequest {
+        view: Default::default(),
         cwd: base.path().to_path_buf(),
         command: "sleep 30".into(),
         env: HashMap::new(),
@@ -254,6 +313,7 @@ async fn spawn_on_existing_branch_checks_it_out() {
     run_git(&["branch", "feature/existing"], base.path());
 
     let req = CreateSessionRequest {
+        view: Default::default(),
         cwd: base.path().to_path_buf(),
         command: "sleep 30".into(),
         env: HashMap::new(),
@@ -323,8 +383,11 @@ async fn spawn_new_branch_creates_worktree_and_runs_in_it() {
     client.kill_session(s.id).await.expect("kill");
 }
 
-/// #66: a second spawn onto a branch that already has a worktree is rejected
-/// with a structured worktree error; the first worktree stays intact.
+/// #66: a second spawn onto an *existing* branch that already has a worktree
+/// is rejected with a structured worktree error; the first worktree stays
+/// intact. (A second `create_branch: true` spawn is a different case: 49ab7e9
+/// suffixes the new branch name instead, see
+/// `colliding_branch_name_gets_suffixed_too`.)
 #[tokio::test(flavor = "multi_thread")]
 async fn second_spawn_on_same_branch_is_rejected() {
     let (_daemon, client) = bring_up().await;
@@ -337,7 +400,7 @@ async fn second_spawn_on_same_branch_is_rejected() {
         .await
         .expect("first spawn");
     let dup = client
-        .spawn_session(&worktree_req(base.path(), "feature/dup", true))
+        .spawn_session(&worktree_req(base.path(), "feature/dup", false))
         .await;
     match dup {
         Err(maestro_e2e::ClientError::Api(maestro_protocol::ClientError::Api { info, .. })) => {
@@ -497,6 +560,57 @@ async fn occupied_path_gets_suffixed_directory_and_both_worktrees_work() {
     );
 }
 
+/// A random handle can reuse the name of a branch left behind by an earlier,
+/// already-removed worktree — `git worktree add -b` refuses outright in that
+/// case, even though the directory is free. The daemon suffixes the branch
+/// itself (not just the directory) and both land on `-2`.
+#[tokio::test(flavor = "multi_thread")]
+async fn colliding_branch_name_gets_suffixed_too() {
+    let (_daemon, client) = bring_up().await;
+
+    let base = TempDir::new().unwrap();
+    init_repo(base.path());
+
+    // No worktree directory in the way, but the branch already exists.
+    run_git(&["branch", "handle"], base.path());
+
+    let s = client
+        .spawn_session(&worktree_req(base.path(), "handle", true))
+        .await
+        .expect("spawn onto a taken branch name");
+
+    let suffixed = base.path().join("worktrees").join("handle-2");
+    assert_eq!(
+        s.cwd, suffixed,
+        "the directory must follow the suffixed branch name"
+    );
+    assert!(suffixed.is_dir());
+
+    let registrations = git_worktree_list(base.path());
+    assert!(
+        registrations.iter().any(|l| l.contains("handle-2")),
+        "the -2 branch's worktree must be registered: {registrations:?}"
+    );
+
+    let branches = String::from_utf8(
+        std::process::Command::new("git")
+            .arg("-C")
+            .arg(base.path())
+            .args(["branch", "--list"])
+            .output()
+            .unwrap()
+            .stdout,
+    )
+    .unwrap();
+    assert!(
+        branches.contains("handle-2"),
+        "the branch itself must be named handle-2: {branches}"
+    );
+
+    let _origin = throwaway_origin(base.path());
+    client.kill_session(s.id).await.expect("kill");
+}
+
 /// #77/#88: the target path holds a plain directory the daemon never made and
 /// git has never heard of. The daemon neither adopts it nor errors — it builds
 /// beside it and leaves every byte of it alone.
@@ -703,6 +817,7 @@ async fn natural_exit_settles_dirty_and_pristine_worktrees_differently() {
 
     let _dirty = client
         .spawn_session(&CreateSessionRequest {
+            view: Default::default(),
             cwd: dirty_repo.path().to_path_buf(),
             command: "sh -c 'echo unsaved > scratch.txt'".into(),
             env: HashMap::new(),
@@ -751,6 +866,7 @@ async fn natural_exit_settles_dirty_and_pristine_worktrees_differently() {
 
 fn create_req_cmd(cwd: &std::path::Path, command: &str, branch: &str) -> CreateSessionRequest {
     CreateSessionRequest {
+        view: Default::default(),
         cwd: cwd.to_path_buf(),
         command: command.into(),
         env: HashMap::new(),
@@ -934,6 +1050,66 @@ async fn daemon_restart_recovers_session() {
     client.kill_session(s.id).await.expect("kill");
 }
 
+#[tokio::test(flavor = "multi_thread")]
+async fn sigterm_stops_structured_child_before_events_ws_drains() {
+    let (mut daemon, client) = bring_up().await;
+    let cwd = TempDir::new().unwrap();
+    let log = cwd.path().join("fake-acp.log");
+    let fake = fake_acp(&log);
+    let session = client
+        .spawn_session(&CreateSessionRequest {
+            view: SessionView::Structured,
+            cwd: cwd.path().to_path_buf(),
+            command: "claude".into(),
+            env: fake.env.clone(),
+            metadata: HashMap::new(),
+            worktree: None,
+        })
+        .await
+        .expect("spawn structured session");
+    let ws_url = daemon.client().events_url().expect("events URL");
+    let (_events_ws, _) = tokio_tungstenite::connect_async(ws_url)
+        .await
+        .expect("events WS handshake");
+    wait_for_async("fake ACP starts", Duration::from_secs(5), || {
+        let log = log.clone();
+        async move { fake_acp_pid(&log).is_some() }
+    })
+    .await;
+    let pid = fake_acp_pid(&log).expect("fake ACP pid");
+
+    daemon.send_sigterm();
+
+    wait_for_async(
+        "fake ACP exits after SIGTERM",
+        Duration::from_secs(5),
+        || async { !pid_alive(pid) },
+    )
+    .await;
+    let sidecar_path = daemon
+        .state_dir()
+        .join("sessions")
+        .join(format!("{}.json", session.id));
+    wait_for_async(
+        "dead structured session sidecar",
+        Duration::from_secs(5),
+        || {
+            let sidecar_path = sidecar_path.clone();
+            async move {
+                std::fs::read(&sidecar_path)
+                    .ok()
+                    .and_then(|json| {
+                        serde_json::from_slice::<maestro_protocol::Session>(&json).ok()
+                    })
+                    .is_some_and(|saved| saved.status == SessionStatus::Dead)
+            }
+        },
+    )
+    .await;
+
+    daemon.stop();
+}
+
 #[tokio::test(flavor = "multi_thread")]
 async fn concurrent_spawns_each_get_unique_ids() {
     let (_daemon, client) = bring_up().await;

crates/maestro-hooks/src/lib.rs

@@ -1,4 +1,4 @@
-//! Claude Code activity hook (#106).
+//! Agent activity hook (#106).
 //!
 //! Two halves, both shared by the `maestro hooks install` CLI subcommand and
 //! the daemon's first-start auto-install:
@@ -6,28 +6,40 @@
 //! * [`HOOK_SCRIPT`] — the hook itself, written to disk at install time. It
 //!   posts an [`ActivityState`](maestro-protocol) to
 //!   `$MAESTRO_URL/api/sessions/$MAESTRO_SESSION_ID/activity` (#105). The same
-//!   global hook runs in every Claude Code session on the machine, so it exits
+//!   global hook runs in every agent session on the machine, so it exits
 //!   0 and silently when either #103 env var is unset, and it never lets a
 //!   daemon failure escape (short curl timeout, status ignored).
-//! * [`install`] — idempotent registration of that script in
-//!   `~/.claude/settings.json`. Only entries maestro itself wrote (identified
-//!   by [`HOOK_MARKER`]) are touched; every other hook and every other field
-//!   in the file is preserved verbatim.
+//! * [`install`] — idempotent registration of that script in one [`Target`]'s
+//!   hook file. Only entries maestro itself wrote (identified by
+//!   [`HOOK_MARKER`]) are touched; every other hook and every other field in
+//!   the file is preserved verbatim.
+//!
+//! One script serves every [`Target`]: Claude Code and Codex read the same
+//! `{"hooks": {Event: [{"hooks": [{"type": "command", "command": …}]}]}}`
+//! shape and hand the hook the same JSON on stdin. Only the file's location
+//! and the event set differ.
 
 use std::path::Path;
 
 /// Marker substring every maestro-installed hook command carries. The
 /// installer rewrites or removes exactly these entries — nothing else in the
 /// user's settings file.
+///
+/// It still says `claude` although the script now serves every [`Target`]:
+/// the marker is how an install from an older maestro is recognised, and
+/// renaming it would orphan every entry already on disk.
 pub const HOOK_MARKER: &str = "maestro-claude-hook";
 
-/// File name of the installed script (carries [`HOOK_MARKER`]).
+/// File name of the installed script (carries [`HOOK_MARKER`]). One script
+/// for every [`Target`] — see the note on [`HOOK_MARKER`] for the name.
 pub const SCRIPT_FILE_NAME: &str = "maestro-claude-hook.sh";
 
-/// Hook events installed only with the `haiku-autoname` feature (#131).
-/// `UserPromptSubmit` carries the prompt the user just submitted; the script
-/// forwards the whole payload to `/api/sessions/:id/prompt`, which names a
-/// still-provisionally-named session after its first one.
+/// Hook events installed only with the `haiku-autoname` feature (#131), for
+/// every [`Target`] — Claude Code and Codex both spell the event
+/// `UserPromptSubmit` and both put the submitted text in the payload's
+/// `prompt`. The script forwards the whole payload to
+/// `/api/sessions/:id/prompt`, which names a still-provisionally-named
+/// session after its first one.
 #[cfg(feature = "haiku-autoname")]
 pub const PROMPT_EVENTS: [(&str, &str); 1] = [("UserPromptSubmit", "Prompt")];
 
@@ -43,7 +55,7 @@ pub const PROMPT_EVENTS: [(&str, &str); 0] = [];
 /// Claude Code's own name for "the turn ended on an API error"; there is no
 /// failure signal in `Stop` or `SessionEnd` payloads, so those never report
 /// `Error`.
-pub const HOOK_EVENTS: [(&str, &str); 5] = [
+pub const CLAUDE_EVENTS: [(&str, &str); 5] = [
     // Tool starting: the agent is demonstrably producing work, even if the
     // tool itself runs for minutes.
     ("PreToolUse", "Active"),
@@ -58,17 +70,86 @@ pub const HOOK_EVENTS: [(&str, &str); 5] = [
     ("StopFailure", "Error"),
 ];
 
+/// Codex hook event → `ActivityState` spelling posted to the daemon.
+///
+/// Codex's event set is close to Claude Code's but not identical: a pending
+/// approval arrives as `PermissionRequest` rather than `Notification`, and
+/// there is no `StopFailure`, so a codex session never reports `Error`.
+pub const CODEX_EVENTS: [(&str, &str); 4] = [
+    ("PreToolUse", "Active"),
+    ("PostToolUse", "Active"),
+    // Codex is blocked on the operator approving a tool call.
+    ("PermissionRequest", "AwaitingInput"),
+    ("Stop", "AwaitingInput"),
+];
+
+/// An agent whose hook file maestro writes into.
+#[derive(Debug, Clone, Copy, PartialEq, Eq)]
+pub enum Target {
+    /// `~/.claude/settings.json`.
+    ClaudeCode,
+    /// `~/.codex/hooks.json`. Codex asks the operator to trust a hook it has
+    /// not seen before, so an install here does nothing until they approve it
+    /// once inside codex — maestro never writes that approval itself.
+    Codex,
+}
+
+impl Target {
+    /// Every target an install covers. Both files are written whether or not
+    /// the agent is on the machine: an unused hook file costs nothing, and
+    /// the alternative is a session spawned after the daemon started missing
+    /// the hook because its agent arrived later.
+    pub const ALL: [Target; 2] = [Target::ClaudeCode, Target::Codex];
+
+    /// How the target is named in logs and CLI output.
+    pub fn label(self) -> &'static str {
+        match self {
+            Target::ClaudeCode => "claude-code",
+            Target::Codex => "codex",
+        }
+    }
+
+    /// The file this target's hook entries are registered in, under `home`.
+    pub fn settings_path(self, home: &Path) -> std::path::PathBuf {
+        match self {
+            Target::ClaudeCode => home.join(".claude/settings.json"),
+            Target::Codex => home.join(".codex/hooks.json"),
+        }
+    }
+
+    /// The activity events this target emits.
+    pub fn activity_events(self) -> &'static [(&'static str, &'static str)] {
+        match self {
+            Target::ClaudeCode => &CLAUDE_EVENTS,
+            Target::Codex => &CODEX_EVENTS,
+        }
+    }
+
+    /// Every event installed for this target: its activity events plus, with
+    /// `haiku-autoname` on, the prompt event both agents spell the same way.
+    pub fn events(self) -> impl Iterator<Item = (&'static str, &'static str)> {
+        self.activity_events()
+            .iter()
+            .chain(PROMPT_EVENTS.iter())
+            .copied()
+    }
+}
+
 /// The shipped hook script. POSIX sh so any `/bin/sh` works.
 pub const HOOK_SCRIPT: &str = r#"#!/bin/sh
-# Installed by maestro (#106): report Claude Code activity to its daemon.
-# Exits silently unless running inside a session maestro spawned (#103 env).
+# Installed by maestro (#106): report agent activity to its daemon.
+# One script for every agent maestro installs hooks into; the state to post
+# is chosen by the caller, so the two event sets differ only in what is
+# registered where. Exits silently unless running inside a session maestro
+# spawned (#103 env).
 # Event -> ActivityState mapping:
-#   PreToolUse    -> Active         (tool started; agent is working)
-#   PostToolUse   -> Active         (tool finished)
-#   Notification  -> AwaitingInput  (permission / idle notice)
-#   Stop          -> AwaitingInput  (turn ended; waiting on the user)
-#   StopFailure   -> Error          (turn ended on an API error)
-#   Prompt        -> the payload is forwarded to the prompt route (#131)
+#   PreToolUse         -> Active         (tool started; agent is working)
+#   PostToolUse        -> Active         (tool finished)
+#   Notification       -> AwaitingInput  (claude code: permission / idle)
+#   PermissionRequest  -> AwaitingInput  (codex: waiting on an approval)
+#   Stop               -> AwaitingInput  (turn ended; waiting on the user)
+#   StopFailure        -> Error          (claude code: turn ended on an error)
+#   Prompt             -> the payload is forwarded to the prompt route (#131)
 state="$1"
 [ -n "$MAESTRO_SESSION_ID" ] || exit 0
 [ -n "$MAESTRO_URL" ] || exit 0
@@ -115,34 +196,29 @@ pub fn script_path(home: &Path) -> std::path::PathBuf {
     home.join(".local/share/maestro").join(SCRIPT_FILE_NAME)
 }
 
-/// The user-level Claude Code settings file for a given home directory.
-pub fn settings_path(home: &Path) -> std::path::PathBuf {
-    home.join(".claude/settings.json")
-}
-
-/// Whether `settings_path` already carries a maestro hook (#106). Presence
-/// only: an install from an older release answers `true` even when it is
-/// missing events this build ships — see [`is_current`].
+/// Whether the file at `settings_path` already carries a maestro hook
+/// (#106). Presence only: an install from an older release answers `true`
+/// even when it is missing events this build ships — see [`is_current`].
 pub fn is_installed(settings_path: &Path) -> bool {
     settings_json(settings_path)
         .map(|root| find_maestro_commands(&root).next().is_some())
         .unwrap_or(false)
 }
 
-/// Whether what is on disk is what this build ships: the script at
-/// `script_path` byte-for-byte, and exactly one settings entry per event in
-/// [`HOOK_EVENTS`] and [`PROMPT_EVENTS`], pointing at that script.
+/// Whether what is on disk is what this build ships for `target`: the script
+/// at `script_path` byte-for-byte, and exactly one settings entry per one of
+/// the target's [`Target::events`], pointing at that script.
 ///
-/// This is the upgrade question. A maestro that gains an event — #131 added
-/// `UserPromptSubmit` long after #106 had installed itself — leaves every
-/// existing user with a present but incomplete install, which
-/// [`is_installed`] cannot tell apart from a current one.
-pub fn is_current(settings_path: &Path, script_path: &Path) -> bool {
+/// This is the upgrade question, asked per [`Target`]. A maestro that gains
+/// an event — #131 added `UserPromptSubmit` long after #106 had installed
+/// itself — leaves every existing user with a present but incomplete
+/// install, which [`is_installed`] cannot tell apart from a current one.
+pub fn is_current(target: Target, settings_path: &Path, script_path: &Path) -> bool {
     if std::fs::read_to_string(script_path).ok().as_deref() != Some(HOOK_SCRIPT) {
         return false;
     }
     settings_json(settings_path)
-        .map(|root| maestro_entries(&root) == expected_entries(script_path))
+        .map(|root| maestro_entries(&root) == expected_entries(target, script_path))
         .unwrap_or(false)
 }
 
@@ -173,14 +249,13 @@ fn maestro_entries(root: &serde_json::Value) -> Vec<(String, String)> {
     found
 }
 
-/// What [`install`] writes for `script_path`, in the same shape.
-fn expected_entries(script_path: &Path) -> Vec<(String, String)> {
-    let mut want: Vec<(String, String)> = HOOK_EVENTS
-        .iter()
-        .chain(PROMPT_EVENTS.iter())
+/// What [`install`] writes for `target` and `script_path`, in the same shape.
+fn expected_entries(target: Target, script_path: &Path) -> Vec<(String, String)> {
+    let mut want: Vec<(String, String)> = target
+        .events()
         .map(|(event, state)| {
             (
-                (*event).to_string(),
+                event.to_string(),
                 format!("{} {state}", script_path.display()),
             )
         })
@@ -207,28 +282,40 @@ pub fn write_script(path: &Path) -> Result<(), HooksError> {
     Ok(())
 }
 
-/// Install the full hook setup for `home`: write the script under
-/// `.local/share/maestro/` and register it in `.claude/settings.json`.
+/// Install the full hook setup for one target under `home`: write the script
+/// under `.local/share/maestro/` and register it in the target's hook file.
 /// Idempotent; returns whether anything changed on disk.
-pub fn install_for_home(home: &Path) -> Result<bool, HooksError> {
+pub fn install_target(target: Target, home: &Path) -> Result<bool, HooksError> {
     let script = script_path(home);
-    let settings = settings_path(home);
+    let settings = target.settings_path(home);
     // A script left over from an older release counts as a change even when
     // the settings entries pointing at it are already right.
-    let changed = !is_current(&settings, &script);
+    let changed = !is_current(target, &settings, &script);
     write_script(&script)?;
-    install(&settings, &script)?;
+    install(target, &settings, &script)?;
     Ok(changed)
 }
 
-/// Register the hook command for every event in [`HOOK_EVENTS`] in the
-/// settings file at `settings_path`. Idempotent: existing maestro entries are
-/// updated in place wherever they sit, stale ones removed, duplicates folded;
-/// every non-maestro entry and every unrelated top-level field survives.
+/// Install for every [`Target::ALL`], reporting each one separately. One
+/// target failing — an unwritable file, unparseable JSON — never stops the
+/// others: an agent whose hook could not be written is one agent without
+/// activity reporting, not a failed install.
+pub fn install_for_home(home: &Path) -> Vec<(Target, Result<bool, HooksError>)> {
+    Target::ALL
+        .iter()
+        .map(|&target| (target, install_target(target, home)))
+        .collect()
+}
+
+/// Register the hook command for every one of `target`'s [`Target::events`]
+/// in the settings file at `settings_path`. Idempotent: existing maestro
+/// entries are updated in place wherever they sit, stale ones removed,
+/// duplicates folded; every non-maestro entry and every unrelated top-level
+/// field survives.
 ///
 /// Never inspects or writes anywhere but `settings_path` — callers pass the
 /// user's real home or a temp one in tests, never a repository.
-pub fn install(settings_path: &Path, script_path: &Path) -> Result<(), HooksError> {
+pub fn install(target: Target, settings_path: &Path, script_path: &Path) -> Result<(), HooksError> {
     let mut root = settings_json(settings_path)?;
 
     // Strip every maestro entry wherever it currently sits, so an older
@@ -236,7 +323,7 @@ pub fn install(settings_path: &Path, script_path: &Path) -> Result<(), HooksErro
     strip_maestro_entries(&mut root);
 
     let hooks = ensure_object(&mut root, "hooks");
-    for (event, state) in HOOK_EVENTS.iter().chain(PROMPT_EVENTS.iter()).copied() {
+    for (event, state) in target.events() {
         let groups = ensure_array(hooks, event);
         let mut group = serde_json::Map::new();
         group.insert(

crates/maestro-hooks/src/tests.rs

@@ -1,15 +1,24 @@
 //! Tests for the shipped hook script (run as a real `/bin/sh` subprocess)
 //! and the settings-file installer. Everything happens under a temp `$HOME`;
-//! the developer's own `~/.claude/settings.json` is never touched.
+//! the developer's own `~/.claude/settings.json` and `~/.codex/hooks.json`
+//! are never touched.
 
 use std::io::{Read, Write};
 use std::process::{Command, Stdio};
 
 use super::*;
 
-/// How many commands one install writes: every activity event, plus the
-/// prompt event when `haiku-autoname` is on (#131).
-const INSTALLED_EVENTS: usize = HOOK_EVENTS.len() + PROMPT_EVENTS.len();
+/// How many commands one install writes for a target: its activity events,
+/// plus the prompt event when `haiku-autoname` is on (#131).
+fn installed_events(target: Target) -> usize {
+    target.events().count()
+}
+
+/// The Claude Code hook file under a temp home. Most installer tests only
+/// need one target, and this is the one they were written against.
+fn settings_path(home: &Path) -> std::path::PathBuf {
+    Target::ClaudeCode.settings_path(home)
+}
 
 fn sh(script: &str, args: &[&str], envs: &[(&str, &str)], payload: &[u8]) -> std::process::Output {
     let mut cmd = Command::new("/bin/sh");
@@ -70,7 +79,7 @@ fn owned_envs<'a>(envs: &'a [(&'static str, String)]) -> Vec<(&'static str, &'a
 /// exit 0, no output, stdin drained.
 #[test]
 fn script_exits_silently_without_maestro_env() {
-    for (event, _) in HOOK_EVENTS {
+    for (event, _) in CLAUDE_EVENTS {
         let out = sh(HOOK_SCRIPT, &[event], &[], br#"{"session_id":"x"}"#);
         assert!(out.status.success(), "{event:?}: {:?}", out.stderr);
         assert!(out.stdout.is_empty(), "{event:?}: {:?}", out.stdout);
@@ -103,7 +112,7 @@ fn script_posts_mapped_state_to_the_activity_endpoint() {
 /// Every event maps to the state the contract specifies.
 #[test]
 fn event_state_mapping_matches_the_contract() {
-    let map: std::collections::HashMap<&str, &str> = HOOK_EVENTS.into_iter().collect();
+    let map: std::collections::HashMap<&str, &str> = CLAUDE_EVENTS.into_iter().collect();
     assert_eq!(map["PreToolUse"], "Active");
     assert_eq!(map["PostToolUse"], "Active");
     assert_eq!(map["Notification"], "AwaitingInput");
@@ -203,10 +212,10 @@ fn fresh_install_registers_every_event() {
     let dir = tempfile::tempdir().unwrap();
     let home = dir.path();
     write_script(&script_path(home)).unwrap();
-    install(&settings_path(home), &script_path(home)).unwrap();
+    install(Target::ClaudeCode, &settings_path(home), &script_path(home)).unwrap();
 
     let cmds = installed_commands(&settings_path(home));
-    assert_eq!(cmds.len(), INSTALLED_EVENTS);
+    assert_eq!(cmds.len(), installed_events(Target::ClaudeCode));
     let joined = cmds.join("\n");
     assert_eq!(joined.matches("Active").count(), 2);
     assert!(joined.contains("Error"));
@@ -221,15 +230,15 @@ fn fresh_install_registers_every_event() {
 fn install_is_idempotent() {
     let dir = tempfile::tempdir().unwrap();
     let home = dir.path();
-    install(&settings_path(home), &script_path(home)).unwrap();
+    install(Target::ClaudeCode, &settings_path(home), &script_path(home)).unwrap();
     let once = std::fs::read_to_string(settings_path(home)).unwrap();
 
-    install(&settings_path(home), &script_path(home)).unwrap();
+    install(Target::ClaudeCode, &settings_path(home), &script_path(home)).unwrap();
     let twice = std::fs::read_to_string(settings_path(home)).unwrap();
     assert_eq!(once, twice);
     assert_eq!(
         installed_commands(&settings_path(home)).len(),
-        INSTALLED_EVENTS
+        installed_events(Target::ClaudeCode)
     );
 }
 
@@ -257,12 +266,12 @@ fn install_updates_an_older_maestro_hook_in_place() {
         .path()
         .join(".local/share/maestro")
         .join(SCRIPT_FILE_NAME);
-    install(&settings, &new_script).unwrap();
+    install(Target::ClaudeCode, &settings, &new_script).unwrap();
 
     let cmds = installed_commands(&settings);
     assert_eq!(
         cmds.len(),
-        INSTALLED_EVENTS,
+        installed_events(Target::ClaudeCode),
         "old entry replaced, not kept: {cmds:?}"
     );
     assert!(!cmds.iter().any(|c| c == old_script));
@@ -298,7 +307,7 @@ fn install_preserves_foreign_hooks_and_removes_stale_maestro_ones() {
         .path()
         .join(".local/share/maestro")
         .join(SCRIPT_FILE_NAME);
-    install(&settings, &new_script).unwrap();
+    install(Target::ClaudeCode, &settings, &new_script).unwrap();
 
     let root: serde_json::Value =
         serde_json::from_str(&std::fs::read_to_string(&settings).unwrap()).unwrap();
@@ -311,7 +320,7 @@ fn install_preserves_foreign_hooks_and_removes_stale_maestro_ones() {
     let cmds = installed_commands(&settings);
     assert_eq!(
         cmds.iter().filter(|c| c.contains(HOOK_MARKER)).count(),
-        INSTALLED_EVENTS,
+        installed_events(Target::ClaudeCode),
         "{cmds:?}"
     );
 }
@@ -321,9 +330,15 @@ fn install_preserves_foreign_hooks_and_removes_stale_maestro_ones() {
 fn is_installed_tracks_reality() {
     let dir = tempfile::tempdir().unwrap();
     let home = dir.path();
-    assert!(!is_installed(&settings_path(home)));
-    install_for_home(home).unwrap();
-    assert!(is_installed(&settings_path(home)));
+    for target in Target::ALL {
+        assert!(!is_installed(&target.settings_path(home)));
+    }
+    for (_, result) in install_for_home(home) {
+        result.unwrap();
+    }
+    for target in Target::ALL {
+        assert!(is_installed(&target.settings_path(home)));
+    }
 }
 
 /// The full home-level install leaves the script executable.
@@ -331,7 +346,9 @@ fn is_installed_tracks_reality() {
 fn install_for_home_writes_an_executable_script() {
     let dir = tempfile::tempdir().unwrap();
     let home = dir.path();
-    install_for_home(home).unwrap();
+    for (_, result) in install_for_home(home) {
+        result.unwrap();
+    }
     #[cfg(unix)]
     {
         use std::os::unix::fs::PermissionsExt;
@@ -350,7 +367,7 @@ fn install_for_home_writes_an_executable_script() {
 fn install_registers_the_prompt_event() {
     let dir = tempfile::tempdir().unwrap();
     let home = dir.path();
-    install(&settings_path(home), &script_path(home)).unwrap();
+    install(Target::ClaudeCode, &settings_path(home), &script_path(home)).unwrap();
 
     let root: serde_json::Value =
         serde_json::from_str(&std::fs::read_to_string(settings_path(home)).unwrap()).unwrap();
@@ -367,7 +384,7 @@ fn install_registers_the_prompt_event() {
 fn install_registers_no_prompt_event_without_the_feature() {
     let dir = tempfile::tempdir().unwrap();
     let home = dir.path();
-    install(&settings_path(home), &script_path(home)).unwrap();
+    install(Target::ClaudeCode, &settings_path(home), &script_path(home)).unwrap();
 
     let root: serde_json::Value =
         serde_json::from_str(&std::fs::read_to_string(settings_path(home)).unwrap()).unwrap();
@@ -436,8 +453,12 @@ fn the_script_posts_a_prompt_payload_unchanged() {
 fn is_current_rejects_an_install_missing_an_event() {
     let dir = tempfile::tempdir().unwrap();
     let home = dir.path();
-    install_for_home(home).unwrap();
-    assert!(is_current(&settings_path(home), &script_path(home)));
+    install_target(Target::ClaudeCode, home).unwrap();
+    assert!(is_current(
+        Target::ClaudeCode,
+        &settings_path(home),
+        &script_path(home)
+    ));
 
     // Drop one event, as an older install would have left the file.
     let mut root: serde_json::Value =
@@ -450,7 +471,11 @@ fn is_current_rejects_an_install_missing_an_event() {
     .unwrap();
 
     assert!(is_installed(&settings_path(home)));
-    assert!(!is_current(&settings_path(home), &script_path(home)));
+    assert!(!is_current(
+        Target::ClaudeCode,
+        &settings_path(home),
+        &script_path(home)
+    ));
 }
 
 /// A settings file that is complete but points at a script from an older
@@ -459,9 +484,13 @@ fn is_current_rejects_an_install_missing_an_event() {
 fn is_current_rejects_a_stale_script() {
     let dir = tempfile::tempdir().unwrap();
     let home = dir.path();
-    install_for_home(home).unwrap();
+    install_target(Target::ClaudeCode, home).unwrap();
     std::fs::write(script_path(home), "#!/bin/sh\nexit 0\n").unwrap();
-    assert!(!is_current(&settings_path(home), &script_path(home)));
+    assert!(!is_current(
+        Target::ClaudeCode,
+        &settings_path(home),
+        &script_path(home)
+    ));
 }
 
 /// Nothing installed at all is not current.
@@ -469,18 +498,93 @@ fn is_current_rejects_a_stale_script() {
 fn is_current_rejects_a_missing_install() {
     let dir = tempfile::tempdir().unwrap();
     let home = dir.path();
-    assert!(!is_current(&settings_path(home), &script_path(home)));
+    assert!(!is_current(
+        Target::ClaudeCode,
+        &settings_path(home),
+        &script_path(home)
+    ));
 }
 
-/// `install_for_home` reports a stale script as a change, even when the
+/// `install_target` reports a stale script as a change, even when the
 /// settings entries pointing at it already read correctly.
 #[test]
-fn install_for_home_reports_a_stale_script_as_a_change() {
+fn install_target_reports_a_stale_script_as_a_change() {
     let dir = tempfile::tempdir().unwrap();
     let home = dir.path();
-    assert!(install_for_home(home).unwrap());
-    assert!(!install_for_home(home).unwrap());
+    assert!(install_target(Target::ClaudeCode, home).unwrap());
+    assert!(!install_target(Target::ClaudeCode, home).unwrap());
 
     std::fs::write(script_path(home), "#!/bin/sh\nexit 0\n").unwrap();
-    assert!(install_for_home(home).unwrap());
+    assert!(install_target(Target::ClaudeCode, home).unwrap());
+}
+
+/// Codex is hooked in its own file, with its own event set: the two agents
+/// share the script but not the events, so neither file carries the other's
+/// spellings (#131 follow-up — a codex session was never named because
+/// nothing installed its `UserPromptSubmit` hook).
+#[test]
+fn each_target_gets_its_own_file_and_events() {
+    let dir = tempfile::tempdir().unwrap();
+    let home = dir.path();
+    for (_, result) in install_for_home(home) {
+        result.unwrap();
+    }
+
+    let claude = events_in(&Target::ClaudeCode.settings_path(home));
+    let codex = events_in(&Target::Codex.settings_path(home));
+    assert_eq!(
+        Target::Codex.settings_path(home),
+        home.join(".codex/hooks.json")
+    );
+
+    // Claude Code's failure signal has no codex equivalent, and codex's
+    // approval notice is spelled differently.
+    assert!(claude.contains(&"StopFailure".to_string()));
+    assert!(claude.contains(&"Notification".to_string()));
+    assert!(!codex.contains(&"StopFailure".to_string()));
+    assert!(!codex.contains(&"Notification".to_string()));
+    assert!(codex.contains(&"PermissionRequest".to_string()));
+
+    // Both report work and both report a finished turn.
+    for event in ["PreToolUse", "PostToolUse", "Stop"] {
+        assert!(claude.contains(&event.to_string()), "claude {event}");
+        assert!(codex.contains(&event.to_string()), "codex {event}");
+    }
+
+    assert_eq!(
+        installed_commands(&Target::Codex.settings_path(home)).len(),
+        installed_events(Target::Codex)
+    );
+}
+
+/// #131: a codex session names itself the same way a Claude Code one does —
+/// same event spelling, same script, same `Prompt` argument.
+#[cfg(feature = "haiku-autoname")]
+#[test]
+fn codex_reports_its_first_prompt_too() {
+    let dir = tempfile::tempdir().unwrap();
+    let home = dir.path();
+    install_target(Target::Codex, home).unwrap();
+
+    let root: serde_json::Value =
+        serde_json::from_str(&std::fs::read_to_string(Target::Codex.settings_path(home)).unwrap())
+            .unwrap();
+    let cmd = root["hooks"]["UserPromptSubmit"][0]["hooks"][0]["command"]
+        .as_str()
+        .unwrap()
+        .to_string();
+    assert!(cmd.ends_with(" Prompt"), "{cmd}");
+    assert!(cmd.contains(SCRIPT_FILE_NAME));
+}
+
+/// Every event name a settings file registers a maestro hook under.
+fn events_in(settings: &Path) -> Vec<String> {
+    serde_json::from_str::<serde_json::Value>(&std::fs::read_to_string(settings).unwrap())
+        .unwrap()
+        .get("hooks")
+        .and_then(|h| h.as_object())
+        .into_iter()
+        .flatten()
+        .map(|(event, _)| event.clone())
+        .collect()
 }

crates/maestro-protocol/src/client.rs

@@ -17,7 +17,7 @@ use crate::routes::{self, UrlError};
 use crate::{
     ApiError, BranchInfo, CreateSessionRequest, DaemonInfo, DirListing, ErrorInfo, GitRoot,
     Project, RecentDirs, RenameSessionRequest, ReportActivityRequest, SendInputRequest, Session,
-    SetFocusRequest,
+    SetFocusRequest, StructuredApprovalDecision, StructuredPromptRequest,
 };
 
 /// Time budget for establishing a TCP connection to the daemon.
@@ -105,6 +105,11 @@ impl DaemonClient {
         Ok(routes::attach_url(&self.base, id)?)
     }
 
+    /// `WS /api/structured/:id` URL for this daemon.
+    pub fn structured_url(&self, id: Uuid) -> Result<String, ClientError> {
+        Ok(routes::structured_url(&self.base, id)?)
+    }
+
     // -- typed calls --------------------------------------------------------
 
     pub async fn list_sessions(&self) -> Result<Vec<Session>, ClientError> {
@@ -179,6 +184,57 @@ impl DaemonClient {
         Ok(())
     }
 
+    /// Send one prompt to a structured session. The daemon rejects a second
+    /// prompt while the preceding ACP turn is still active.
+    pub async fn send_structured_prompt(&self, id: Uuid, prompt: &str) -> Result<(), ClientError> {
+        let req = StructuredPromptRequest {
+            prompt: prompt.to_string(),
+        };
+        let resp = self
+            .send(
+                Method::POST,
+                &routes::structured_prompt(id),
+                &[],
+                Some(&req),
+            )
+            .await?;
+        check(resp).await?;
+        Ok(())
+    }
+
+    /// Cancel the structured session's active ACP turn.
+    pub async fn cancel_structured_turn(&self, id: Uuid) -> Result<(), ClientError> {
+        let resp = self
+            .send(
+                Method::POST,
+                &routes::structured_cancel(id),
+                &[],
+                None::<&()>,
+            )
+            .await?;
+        check(resp).await?;
+        Ok(())
+    }
+
+    /// Resolve the currently pending structured-session permission request.
+    pub async fn resolve_structured_approval(
+        &self,
+        id: Uuid,
+        nonce: &str,
+        decision: StructuredApprovalDecision,
+    ) -> Result<(), ClientError> {
+        let resp = self
+            .send(
+                Method::POST,
+                &routes::structured_approval(id, nonce),
+                &[],
+                Some(&decision),
+            )
+            .await?;
+        check(resp).await?;
+        Ok(())
+    }
+
     pub async fn daemon_info(&self) -> Result<DaemonInfo, ClientError> {
         self.get(routes::INFO, &[]).await
     }

crates/maestro-protocol/src/display.rs

@@ -202,6 +202,41 @@ pub fn command_program(command: &str) -> String {
     }
 }
 
+/// Program name (already basenamed and lowercased) -> the tool id its mark
+/// stands for. Mirrors the web's `BY_PROGRAM` in `web/src/toolIcon.ts`;
+/// recognition is deliberately narrow, so an unrecognised program has no tool.
+const BY_PROGRAM: [(&str, &str); 17] = [
+    ("claude", "claude"),
+    ("claude-code", "claude"),
+    ("codex", "codex"),
+    ("opencode", "opencode"),
+    ("gemini", "gemini"),
+    ("aider", "aider"),
+    ("cursor", "cursor"),
+    ("cursor-agent", "cursor"),
+    ("pi", "pi"),
+    ("bash", "shell"),
+    ("zsh", "shell"),
+    ("sh", "shell"),
+    ("fish", "shell"),
+    ("dash", "shell"),
+    ("ksh", "shell"),
+    ("nu", "shell"),
+    ("xonsh", "shell"),
+];
+
+/// The tool id a command line's icon stands for (`claude`, `codex`,
+/// `opencode`, ...), or `None` when the program is not one we have a mark for.
+/// The command bar matches this field (`docs/COMMAND-BAR.md`), so it must name
+/// the same tools the web's `splitCommand().tool` does.
+pub fn command_tool(command: &str) -> Option<&'static str> {
+    let program = command_program(command).to_lowercase();
+    BY_PROGRAM
+        .iter()
+        .find(|(name, _)| *name == program)
+        .map(|(_, tool)| *tool)
+}
+
 /// `FOO=bar`, the shell's own prefix for one command's environment.
 fn is_env_assignment(word: &str) -> bool {
     let mut chars = word.chars();
@@ -233,6 +268,7 @@ mod tests {
 
     fn session(cwd: &str) -> Session {
         Session {
+            view: Default::default(),
             id: Uuid::from_u128(1),
             cwd: PathBuf::from(cwd),
             command: "bash".into(),
@@ -248,6 +284,8 @@ mod tests {
             activity_since: Utc::now(),
             current_cwd: None,
             blocked_work: None,
+            last_focused_at: None,
+            acp_session_id: None,
         }
     }
 
@@ -475,4 +513,22 @@ mod tests {
         assert_eq!(command_program("sudo"), "sudo");
         assert_eq!(command_program(""), "");
     }
+
+    /// The command bar's `tool` field (docs/COMMAND-BAR.md) names the same
+    /// tools the web's `splitCommand().tool` does.
+    #[test]
+    fn command_tool_names_the_mark_the_card_shows() {
+        assert_eq!(command_tool("claude --resume"), Some("claude"));
+        assert_eq!(command_tool("npx opencode"), Some("opencode"));
+        assert_eq!(command_tool("/bin/zsh -l"), Some("shell"));
+        assert_eq!(command_tool("CLAUDE"), Some("claude"));
+    }
+
+    /// Narrow on purpose: an unrecognised program has no mark, so the
+    /// candidate has no `tool` field to match rather than a wrong one.
+    #[test]
+    fn command_tool_is_absent_for_an_unrecognised_program() {
+        assert_eq!(command_tool("hx src/main.rs"), None);
+        assert_eq!(command_tool(""), None);
+    }
 }

crates/maestro-protocol/src/lib.rs

@@ -108,6 +108,41 @@ pub struct Session {
     /// from daemons that predate the field stay forward-compatible.
     #[serde(default)]
     pub blocked_work: Option<InTheWay>,
+    /// Wall-clock time this session last became the pane a client was
+    /// showing (#145) — stamped by both `POST /.../focus` and opening
+    /// `/api/attach/:id`, since either one is the operator moving there.
+    /// `None` until the session has been focused at least once, which is
+    /// also how the command bar's empty-query ordering (`docs/COMMAND-BAR.md`)
+    /// sorts a never-focused session after every session that has one.
+    #[serde(default)]
+    pub last_focused_at: Option<DateTime<Utc>>,
+    /// Whether this session's process is a plain terminal (PTY bytes through
+    /// tmux) or a structured agent driven over ACP rows (#133). Fixed at
+    /// spawn time and never changes for the life of the session. Defaults to
+    /// `Terminal` on the wire so every existing client and payload from a
+    /// daemon that predates the field keeps working untouched.
+    #[serde(default)]
+    pub view: SessionView,
+    /// The ACP session id the `claude-code-acp` adapter handed back from
+    /// `session/new` (#134). Only a [`SessionView::Structured`] session has
+    /// one, and only once its handshake succeeded; a later respawn passes it
+    /// to `session/load` so the conversation continues (#135). Distinct from
+    /// the hook-reported Claude Code conversation id (#161): that one is what
+    /// `claude --resume` takes, this one is what the ACP adapter takes, and
+    /// the two are minted by different processes with different lifetimes.
+    #[serde(default, skip_serializing_if = "Option::is_none")]
+    pub acp_session_id: Option<String>,
+}
+
+/// A session's process shape (#133): a plain terminal, or a structured agent
+/// driven over ACP rows. Chosen at spawn and immutable for the session's
+/// life. `Terminal` is the default — every sidecar and `CreateSessionRequest`
+/// written before this field existed meant a terminal session.
+#[derive(Debug, Clone, Copy, PartialEq, Eq, Serialize, Deserialize, Default)]
+pub enum SessionView {
+    #[default]
+    Terminal,
+    Structured,
 }
 
 /// Default for [`Session::last_activity_at`] when an older payload omits it.
@@ -121,9 +156,9 @@ pub enum SessionStatus {
     Dead,
 }
 
-/// Inferred session activity, orthogonal to [`SessionStatus`] (NAP-340). The
-/// daemon derives this from tmux pane state, PTY quiescence, and `/proc`
-/// inspection — never by parsing the terminal byte stream.
+/// Session activity, orthogonal to [`SessionStatus`] (NAP-340). Terminal
+/// sessions use pane/process inference and agent reports; structured sessions
+/// use their ACP turn lifecycle (docs/SIDEBAR.md).
 ///
 /// Deserializes leniently (#110, SIDEBAR.md Precedence): an unknown variant
 /// from a newer daemon becomes [`ActivityState::Idle`] instead of failing the
@@ -131,15 +166,14 @@ pub enum SessionStatus {
 /// forgiven.
 #[derive(Debug, Clone, Copy, PartialEq, Eq, Serialize, Default)]
 pub enum ActivityState {
-    /// Producing output, or the foreground process is busy.
+    /// Producing output, the foreground process is busy, or an ACP turn is active.
     Active,
     /// Foreground process alive but quiescent. The forward-compatible default.
     #[default]
     Idle,
-    /// Blocked on a `read()` from the pty — waiting on the user.
+    /// Blocked on terminal input or waiting for an ACP approval.
     AwaitingInput,
-    /// The agent running in the session reported a failure (#102). Never
-    /// inferred by the daemon; only set when an agent reports it (#105).
+    /// An agent reported a failure, or a structured session/turn failed.
     Error,
 }
 
@@ -344,6 +378,11 @@ pub struct CreateSessionRequest {
     pub metadata: HashMap<String, Value>,
     #[serde(default)]
     pub worktree: Option<WorktreeSpec>,
+    /// The process shape to spawn (#133). Defaulted so every existing client
+    /// and `curl` against the API keeps requesting a `Terminal` session
+    /// untouched.
+    #[serde(default)]
+    pub view: SessionView,
 }
 
 /// Result of `GET /api/dirs`: the immediate subdirectories of one directory.
@@ -546,6 +585,12 @@ pub struct DaemonInfo {
     /// network blip, even when the build did not change.
     #[serde(default)]
     pub instance: String,
+    /// Canonical leader key the operator configured (`[tui].leader`, default
+    /// `ctrl-a`), served so the web client binds the same chord the TUI does
+    /// instead of its own hardcoded constant (#159). Empty from a daemon too
+    /// old to serve it, which clients read as "use your default".
+    #[serde(default)]
+    pub leader: String,
 }
 
 /// Payload of `GET /api/names?count=N` (#53) — a batch of fresh
@@ -709,6 +754,132 @@ pub enum CatalogEvent {
     },
 }
 
+// ---------------------------------------------------------------------------
+// Structured-session projections
+// ---------------------------------------------------------------------------
+
+/// One client-neutral item in a structured session transcript.
+///
+/// `data` preserves the ACP payload without committing clients to an ACP
+/// dependency. Rendering choices, including markdown and tool-card treatment,
+/// stay with the client.
+#[derive(Debug, Clone, PartialEq, Serialize, Deserialize)]
+pub struct TranscriptRow {
+    /// Stable within one session, so later deltas can address this row.
+    pub id: String,
+    pub kind: TranscriptRowKind,
+    pub data: Value,
+}
+
+/// The semantic shape of a [`TranscriptRow`].
+#[derive(Debug, Clone, Copy, PartialEq, Eq, Serialize, Deserialize)]
+#[serde(rename_all = "snake_case")]
+pub enum TranscriptRowKind {
+    User,
+    AgentText,
+    AgentThought,
+    ToolCall,
+    ToolDiff,
+    Approval,
+    Plan,
+    Notice,
+}
+
+/// A complete transcript at a durable event-log position.
+#[derive(Debug, Clone, PartialEq, Serialize, Deserialize)]
+pub struct TranscriptSnapshot {
+    pub cursor: u64,
+    #[serde(default)]
+    pub rows: Vec<TranscriptRow>,
+}
+
+/// One durable, client-neutral replay step from a structured session.
+///
+/// Results are ordered by increasing `cursor`. `since` returns the first
+/// matching steps; `before` returns the final matching steps, still increasing.
+#[derive(Debug, Clone, PartialEq, Serialize, Deserialize)]
+pub struct StructuredReplayEvent {
+    /// Durable ACP-log position represented by this projected step.
+    pub cursor: u64,
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub transcript: Option<TranscriptDelta>,
+    pub state: ReducedState,
+}
+
+/// A change to a transcript row.
+#[derive(Debug, Clone, PartialEq, Serialize, Deserialize)]
+#[serde(tag = "type", rename_all = "snake_case")]
+pub enum TranscriptDelta {
+    Append { row: TranscriptRow },
+    Patch { row: TranscriptRow },
+    Remove { id: String },
+}
+
+/// Per-turn indicators derived from the ACP stream.
+#[derive(Debug, Clone, Default, PartialEq, Eq, Serialize, Deserialize)]
+pub struct TurnState {
+    #[serde(default)]
+    pub responding: bool,
+    #[serde(default)]
+    pub thinking: bool,
+    #[serde(default)]
+    pub active_tool_calls: Vec<String>,
+}
+
+/// A whole-session view derived from ACP notifications.
+///
+/// Values whose shape ACP owns are carried as JSON so this wire protocol stays
+/// forward-compatible when ACP adds fields or variants.
+#[derive(Debug, Clone, Default, PartialEq, Serialize, Deserialize)]
+pub struct ReducedState {
+    #[serde(default)]
+    pub turn: TurnState,
+    #[serde(default, skip_serializing_if = "Option::is_none")]
+    pub pending_approval: Option<Value>,
+    #[serde(default, skip_serializing_if = "Option::is_none")]
+    pub plan: Option<Value>,
+    #[serde(default, skip_serializing_if = "Option::is_none")]
+    pub usage: Option<Value>,
+    #[serde(default, skip_serializing_if = "Option::is_none")]
+    pub context: Option<Value>,
+    #[serde(default, skip_serializing_if = "Option::is_none")]
+    pub model: Option<String>,
+    #[serde(default, skip_serializing_if = "Option::is_none")]
+    pub mode: Option<String>,
+}
+
+/// Server messages sent over a structured-session WebSocket.
+#[derive(Debug, Clone, PartialEq, Serialize, Deserialize)]
+#[serde(tag = "type", rename_all = "snake_case")]
+pub enum StructuredEvent {
+    TranscriptSnapshot {
+        snapshot: TranscriptSnapshot,
+    },
+    ReducedState {
+        state: ReducedState,
+    },
+    ProjectionUpdate {
+        #[serde(skip_serializing_if = "Option::is_none")]
+        transcript: Option<TranscriptDelta>,
+        state: ReducedState,
+    },
+}
+
+/// HTTP body for `POST /api/sessions/:id/structured/prompt`.
+#[derive(Debug, Clone, PartialEq, Eq, Serialize, Deserialize)]
+pub struct StructuredPromptRequest {
+    pub prompt: String,
+}
+
+/// Operator decision for a pending ACP permission request.
+#[derive(Debug, Clone, Copy, PartialEq, Eq, Serialize, Deserialize)]
+#[serde(rename_all = "snake_case")]
+pub enum StructuredApprovalDecision {
+    AllowOnce,
+    AllowForSession,
+    Deny,
+}
+
 // ---------------------------------------------------------------------------
 // Client ↔ Daemon control messages (text frames on the attach WS)
 // ---------------------------------------------------------------------------
@@ -847,6 +1018,9 @@ mod tests {
                 .with_timezone(&Utc),
             current_cwd: Some(PathBuf::from("/home/naps62/projects/maestro/crates")),
             blocked_work: None,
+            last_focused_at: None,
+            view: SessionView::Terminal,
+            acp_session_id: None,
         }
     }
 
@@ -896,6 +1070,28 @@ mod tests {
         );
     }
 
+    #[test]
+    fn last_focused_at_defaults_to_none_on_legacy_payload() {
+        // Pre-#145 payload omits the field; `None` means never-focused.
+        let json = serde_json::json!({
+            "id": Uuid::from_u128(1),
+            "cwd": "/tmp",
+            "command": "bash",
+            "status": "Running",
+            "created_at": "2026-05-24T12:00:00Z"
+        });
+        let s: Session = serde_json::from_value(json).unwrap();
+        assert_eq!(s.last_focused_at, None);
+
+        let mut focused = sample_session();
+        focused.last_focused_at = Some(
+            DateTime::parse_from_rfc3339("2026-05-24T12:06:00Z")
+                .unwrap()
+                .with_timezone(&Utc),
+        );
+        assert_eq!(focused, round_trip(&focused));
+    }
+
     #[test]
     fn activity_since_defaults_to_epoch_on_legacy_payload() {
         // A daemon predating #102 omits `activity_since`; it must deserialize
@@ -1036,6 +1232,7 @@ mod tests {
                 branch: "feat/foo".into(),
                 create_branch: true,
             }),
+            view: SessionView::Terminal,
         };
         assert_eq!(req, round_trip(&req));
     }
@@ -1050,6 +1247,74 @@ mod tests {
         assert!(req.worktree.is_none());
         assert!(req.env.is_empty());
         assert!(req.metadata.is_empty());
+        assert_eq!(req.view, SessionView::Terminal);
+    }
+
+    #[test]
+    fn session_view_defaults_to_terminal_on_legacy_payload() {
+        // A pre-#133 daemon or client omits `view`; it must deserialize to
+        // `Terminal` rather than failing, and `Structured` round-trips.
+        let json = serde_json::json!({
+            "id": Uuid::from_u128(1),
+            "cwd": "/tmp",
+            "command": "bash",
+            "status": "Running",
+            "created_at": "2026-05-24T12:00:00Z"
+        });
+        let s: Session = serde_json::from_value(json).unwrap();
+        assert_eq!(s.view, SessionView::Terminal);
+
+        let mut structured = sample_session();
+        structured.view = SessionView::Structured;
+        assert_eq!(structured, round_trip(&structured));
+    }
+
+    #[test]
+    fn structured_projection_types_round_trip_and_default() {
+        let row = TranscriptRow {
+            id: "tool:read-1".into(),
+            kind: TranscriptRowKind::ToolCall,
+            data: serde_json::json!({"name": "vendor.read", "title": "Read"}),
+        };
+        let snapshot = TranscriptSnapshot {
+            cursor: 7,
+            rows: vec![row.clone()],
+        };
+        assert_eq!(snapshot, round_trip(&snapshot));
+        assert_eq!(
+            TranscriptDelta::Patch { row: row.clone() },
+            round_trip(&TranscriptDelta::Patch { row })
+        );
+
+        let state: ReducedState = serde_json::from_value(serde_json::json!({})).unwrap();
+        assert_eq!(state, ReducedState::default());
+        assert_eq!(
+            serde_json::to_value(TranscriptRowKind::AgentThought).unwrap(),
+            serde_json::json!("agent_thought")
+        );
+    }
+
+    #[test]
+    fn acp_session_id_defaults_to_none_and_round_trips() {
+        // A payload from before #134 carries no `acp_session_id`; it must
+        // read as `None`, stay off the wire while unset, and round-trip
+        // once the adapter has handed one back.
+        let json = serde_json::json!({
+            "id": Uuid::from_u128(1),
+            "cwd": "/tmp",
+            "command": "bash",
+            "status": "Running",
+            "created_at": "2026-05-24T12:00:00Z"
+        });
+        let s: Session = serde_json::from_value(json).unwrap();
+        assert_eq!(s.acp_session_id, None);
+        let serialized = serde_json::to_value(&s).unwrap();
+        assert!(serialized.get("acp_session_id").is_none());
+
+        let mut structured = sample_session();
+        structured.view = SessionView::Structured;
+        structured.acp_session_id = Some("sess_01HZX".into());
+        assert_eq!(structured, round_trip(&structured));
     }
 
     /// A client that predates the new/existing discriminator sends no

crates/maestro-protocol/src/routes.rs

@@ -71,6 +71,31 @@ pub fn attach(id: Uuid) -> String {
     format!("{API_PREFIX}/attach/{id}")
 }
 
+/// `WS /api/structured/:id` — transcript/state snapshots and live deltas.
+pub fn structured(id: Uuid) -> String {
+    format!("{API_PREFIX}/structured/{id}")
+}
+
+/// `GET /api/sessions/:id/structured/replay` — cursor-bounded ACP history.
+pub fn structured_replay(id: Uuid) -> String {
+    format!("{SESSIONS}/{id}/structured/replay")
+}
+
+/// `POST /api/sessions/:id/structured/prompt` — send an ACP prompt.
+pub fn structured_prompt(id: Uuid) -> String {
+    format!("{SESSIONS}/{id}/structured/prompt")
+}
+
+/// `POST /api/sessions/:id/structured/cancel` — cancel an ACP turn.
+pub fn structured_cancel(id: Uuid) -> String {
+    format!("{SESSIONS}/{id}/structured/cancel")
+}
+
+/// `POST /api/sessions/:id/structured/approvals/:nonce` — answer ACP permission.
+pub fn structured_approval(id: Uuid, nonce: &str) -> String {
+    format!("{SESSIONS}/{id}/structured/approvals/{nonce}")
+}
+
 /// Axum-style patterns for the two parameterised routes, so the server
 /// registers the same paths [`session`] and [`attach`] build.
 pub mod patterns {
@@ -80,6 +105,11 @@ pub mod patterns {
     pub const SESSION_PROMPT: &str = "/api/sessions/:id/prompt";
     pub const SESSION_FOCUS: &str = "/api/sessions/:id/focus";
     pub const ATTACH: &str = "/api/attach/:id";
+    pub const STRUCTURED: &str = "/api/structured/:id";
+    pub const STRUCTURED_REPLAY: &str = "/api/sessions/:id/structured/replay";
+    pub const STRUCTURED_PROMPT: &str = "/api/sessions/:id/structured/prompt";
+    pub const STRUCTURED_CANCEL: &str = "/api/sessions/:id/structured/cancel";
+    pub const STRUCTURED_APPROVAL: &str = "/api/sessions/:id/structured/approvals/:nonce";
 }
 
 /// A daemon base URL that could not be turned into a WebSocket base.
@@ -129,6 +159,11 @@ pub fn attach_url(http_base: &str, id: Uuid) -> Result<String, UrlError> {
     Ok(format!("{}{}", ws_base(http_base)?, attach(id)))
 }
 
+/// Full `WS /api/structured/:id` URL for a daemon reachable at `http_base`.
+pub fn structured_url(http_base: &str, id: Uuid) -> Result<String, UrlError> {
+    Ok(format!("{}{}", ws_base(http_base)?, structured(id)))
+}
+
 #[cfg(test)]
 mod tests {
     use super::*;
@@ -178,6 +213,10 @@ mod tests {
             events_url("http://host:7070/").unwrap(),
             "ws://host:7070/api/events"
         );
+        assert_eq!(
+            structured_url("http://host:7070/", id()).unwrap(),
+            "ws://host:7070/api/structured/6f1a7c0e-0f5e-4a2b-9a3d-6b1c2d3e4f50"
+        );
     }
 
     #[test]
@@ -206,6 +245,22 @@ mod tests {
             attach(id()),
             "/api/attach/6f1a7c0e-0f5e-4a2b-9a3d-6b1c2d3e4f50"
         );
+        assert_eq!(
+            structured(id()),
+            "/api/structured/6f1a7c0e-0f5e-4a2b-9a3d-6b1c2d3e4f50"
+        );
+        assert_eq!(
+            structured_replay(id()),
+            "/api/sessions/6f1a7c0e-0f5e-4a2b-9a3d-6b1c2d3e4f50/structured/replay"
+        );
+        assert_eq!(
+            structured_prompt(id()),
+            "/api/sessions/6f1a7c0e-0f5e-4a2b-9a3d-6b1c2d3e4f50/structured/prompt"
+        );
+        assert_eq!(
+            structured_cancel(id()),
+            "/api/sessions/6f1a7c0e-0f5e-4a2b-9a3d-6b1c2d3e4f50/structured/cancel"
+        );
         assert_eq!(
             attach_url("https://laptop.lan:7070", id()).unwrap(),
             "wss://laptop.lan:7070/api/attach/6f1a7c0e-0f5e-4a2b-9a3d-6b1c2d3e4f50"
@@ -240,6 +295,22 @@ mod tests {
             patterns::ATTACH.trim_end_matches(":id"),
             attach(id()).trim_end_matches(&id().to_string())
         );
+        assert_eq!(
+            patterns::STRUCTURED.trim_end_matches(":id"),
+            structured(id()).trim_end_matches(&id().to_string())
+        );
+        assert_eq!(
+            patterns::STRUCTURED_REPLAY.trim_end_matches(":id/structured/replay"),
+            session(id()).trim_end_matches(&id().to_string())
+        );
+        assert_eq!(
+            patterns::STRUCTURED_PROMPT.trim_end_matches(":id/structured/prompt"),
+            session(id()).trim_end_matches(&id().to_string())
+        );
+        assert_eq!(
+            patterns::STRUCTURED_CANCEL.trim_end_matches(":id/structured/cancel"),
+            session(id()).trim_end_matches(&id().to_string())
+        );
     }
 
     #[test]
@@ -258,5 +329,9 @@ mod tests {
             assert!(path.starts_with(API_PREFIX), "{path} escapes {API_PREFIX}");
         }
         assert!(attach(id()).starts_with(API_PREFIX));
+        assert!(structured(id()).starts_with(API_PREFIX));
+        assert!(structured_replay(id()).starts_with(API_PREFIX));
+        assert!(structured_prompt(id()).starts_with(API_PREFIX));
+        assert!(structured_cancel(id()).starts_with(API_PREFIX));
     }
 }

crates/maestro-testing/src/lib.rs

@@ -31,6 +31,7 @@ use uuid::Uuid;
 /// Build a plausible `Session` for a test to hand to [`MockDaemon::add_session`].
 pub fn session(id: Uuid, cwd: &str, command: &str) -> Session {
     Session {
+        view: Default::default(),
         id,
         cwd: cwd.into(),
         command: command.into(),
@@ -46,6 +47,8 @@ pub fn session(id: Uuid, cwd: &str, command: &str) -> Session {
         activity_since: chrono::Utc::now(),
         current_cwd: None,
         blocked_work: None,
+        last_focused_at: None,
+        acp_session_id: None,
     }
 }
 

crates/maestro-tui/Cargo.toml

@@ -21,6 +21,7 @@ thiserror.workspace = true
 tokio = { workspace = true, features = ["sync", "time", "macros", "rt"] }
 tokio-tungstenite.workspace = true
 tracing.workspace = true
+unicode-width.workspace = true
 uuid.workspace = true
 vt100.workspace = true
 

crates/maestro-tui/src/action.rs

@@ -53,6 +53,17 @@ pub enum Action {
     RenameHighlighted,
 
     // Chrome
+    /// Open the `ctrl-k` command bar (`docs/COMMAND-BAR.md`) — a query line
+    /// over the sessions, ranked by the shared matcher.
+    OpenCommandBar,
+    /// Escape hatch (#156): leader then `ctrl-k` sends the literal `0x0B`
+    /// byte to the focused pane instead of opening the command bar, giving
+    /// readline's kill-to-end-of-line back.
+    SendLiteralCtrlK,
+    /// Escape hatch (#158): the leader pressed twice sends one literal
+    /// leader byte to the focused pane and drops the pending chord, the way
+    /// tmux resolves a doubled prefix key.
+    SendLiteralLeader,
     ToggleSidebar,
     ShowHelp,
     Quit,
@@ -94,6 +105,9 @@ impl Action {
             Action::FastForwardSpawn => "Create session with defaults".into(),
             Action::KillHighlighted => "Kill selected session".into(),
             Action::RenameHighlighted => "Rename selected session".into(),
+            Action::OpenCommandBar => "Go to a session".into(),
+            Action::SendLiteralCtrlK => "Send literal Ctrl-K to session".into(),
+            Action::SendLiteralLeader => "Send literal leader key to session".into(),
             Action::ToggleSidebar => "Show or hide sidebar".into(),
             Action::ShowHelp => "Show help".into(),
             Action::Quit => "Quit Maestro".into(),
@@ -120,6 +134,9 @@ impl Action {
             "FastForwardSpawn" => return Ok(Action::FastForwardSpawn),
             "KillHighlighted" => return Ok(Action::KillHighlighted),
             "RenameHighlighted" => return Ok(Action::RenameHighlighted),
+            "OpenCommandBar" => return Ok(Action::OpenCommandBar),
+            "SendLiteralCtrlK" => return Ok(Action::SendLiteralCtrlK),
+            "SendLiteralLeader" => return Ok(Action::SendLiteralLeader),
             "ToggleSidebar" => return Ok(Action::ToggleSidebar),
             "ShowHelp" => return Ok(Action::ShowHelp),
             "Quit" => return Ok(Action::Quit),
@@ -239,10 +256,38 @@ mod tests {
         );
     }
 
+    /// The command bar is an ordinary keymap entry, so it must round-trip
+    /// like every other action (#153).
+    #[test]
+    fn open_command_bar_round_trips() {
+        assert_eq!(
+            Action::parse("OpenCommandBar").unwrap(),
+            Action::OpenCommandBar
+        );
+        assert_eq!(Action::OpenCommandBar.to_string(), "OpenCommandBar");
+        assert_eq!(Action::OpenCommandBar.help_label(), "Go to a session");
+    }
+
+    /// The escape hatch (#156) is an ordinary action like any other.
+    #[test]
+    fn send_literal_ctrl_k_round_trips() {
+        assert_eq!(
+            Action::parse("SendLiteralCtrlK").unwrap(),
+            Action::SendLiteralCtrlK
+        );
+        assert_eq!(Action::SendLiteralCtrlK.to_string(), "SendLiteralCtrlK");
+        assert_eq!(
+            Action::SendLiteralCtrlK.help_label(),
+            "Send literal Ctrl-K to session"
+        );
+    }
+
     #[test]
     fn display_round_trips() {
         for a in [
             Action::EnterInsert,
+            Action::OpenCommandBar,
+            Action::SendLiteralCtrlK,
             Action::RenameHighlighted,
             Action::Quit,
             Action::OpenSpawnModal,

crates/maestro-tui/src/catalog.rs

@@ -207,6 +207,7 @@ mod tests {
 
     fn session(id: u128, command: &str) -> Session {
         Session {
+            view: Default::default(),
             id: Uuid::from_u128(id),
             command: command.into(),
             cwd: std::path::PathBuf::from("/tmp"),
@@ -222,6 +223,8 @@ mod tests {
             activity_since: chrono::Utc::now(),
             current_cwd: None,
             blocked_work: None,
+            last_focused_at: None,
+            acp_session_id: None,
         }
     }
 

crates/maestro-tui/src/config.rs

@@ -52,10 +52,11 @@ const DEFAULT_NORMAL: &[(&str, &str)] = &[
     // because Normal mode only exists while the sidebar is focused, so
     // nothing forwards it to a pty.
     ("tab", "AttachHighlighted"),
-    ("s", "OpenSpawnModal"),
-    // Fast-forward spawn (#67): the spawn key's neighbour does the same
+    // `n`/`N`, the same pair the web client binds.
+    ("n", "OpenSpawnModal"),
+    // Fast-forward spawn (#67): the spawn key's shifted twin does the same
     // thing with every default resolved and no form.
-    ("S", "FastForwardSpawn"),
+    ("N", "FastForwardSpawn"),
     ("x", "KillHighlighted"),
     ("r", "RenameHighlighted"),
     // Focus
@@ -64,6 +65,9 @@ const DEFAULT_NORMAL: &[(&str, &str)] = &[
     ("pageup", "ScrollPanePageUp"),
     ("pagedown", "ScrollPanePageDown"),
     // Chrome
+    // The command bar (#153). An ordinary entry, so it is rebindable and the
+    // help overlay picks it up from the live keymap.
+    ("ctrl-k", "OpenCommandBar"),
     ("ctrl-w b", "ToggleSidebar"),
     ("?", "ShowHelp"),
     ("ctrl-w q", "Quit"),
@@ -74,10 +78,17 @@ const DEFAULT_NORMAL: &[(&str, &str)] = &[
     ("mouse:dblclick(sidebar-row)", "AttachHighlighted"),
 ];
 
-/// Default Insert-mode bindings. The leader (`LeaveInsert`) is inserted
-/// dynamically by [`TuiConfig::load`] so rebinding it rebinds its Insert
-/// escape automatically; `esc` is a second, fixed way back to the sidebar.
-const DEFAULT_INSERT: &[(&str, &str)] = &[("esc", "LeaveInsert")];
+/// Default Insert-mode bindings — almost empty on purpose. Every key typed in
+/// Insert mode belongs to the session, `esc` included: full-screen apps read
+/// it constantly, so binding it here would make it unreachable. The only way
+/// back to the sidebar is the leader (`LeaveInsert`), which
+/// [`TuiConfig::load`] inserts dynamically so rebinding the leader rebinds
+/// the Insert escape with it.
+///
+/// The one exception is the command bar (#153): `ctrl-k` opens it from inside
+/// a pane too, so `docs/COMMAND-BAR.md`'s "from anywhere" holds. Readline's
+/// kill-to-end-of-line is given back through the leader (#156).
+const DEFAULT_INSERT: &[(&str, &str)] = &[("ctrl-k", "OpenCommandBar")];
 
 impl TuiConfig {
     /// Build a runtime config from a [`TuiSection`] (typically the `tui`
@@ -103,7 +114,7 @@ impl TuiConfig {
             TuiTheme::Nord => Palette::NORD,
             TuiTheme::Dracula => Palette::DRACULA,
         };
-        let leader_str = section.leader.as_deref().unwrap_or("ctrl-a");
+        let leader_str = section.leader();
         let leader = InputKey::parse(leader_str)
             .map_err(|_| TuiConfigError::BadLeader(leader_str.to_string()))?;
         let chord_timeout = Duration::from_millis(section.chord_timeout_ms.unwrap_or(1000));
@@ -135,6 +146,25 @@ impl TuiConfig {
         keymap
             .set(Mode::Insert, &leader.canonical(), "LeaveInsert")
             .expect("leader canonical form is valid by construction");
+        // Leader, ctrl-k → the literal-Ctrl-K escape hatch (#156), built from
+        // the same leader spec so rebinding leader rebinds this chord too.
+        keymap
+            .set(
+                Mode::Insert,
+                &format!("{} ctrl-k", leader.canonical()),
+                "SendLiteralCtrlK",
+            )
+            .expect("leader canonical form is valid by construction");
+        // Leader, leader → the literal-leader escape hatch (#158), tmux-style:
+        // pressing it twice sends the leader byte itself. Built from the same
+        // leader spec, so rebinding leader rebinds this chord too.
+        keymap
+            .set(
+                Mode::Insert,
+                &format!("{} {}", leader.canonical(), leader.canonical()),
+                "SendLiteralLeader",
+            )
+            .expect("leader canonical form is valid by construction");
 
         for (input, action) in &section.keymap_normal {
             keymap.set(Mode::Normal, input, action).map_err(|source| {
@@ -220,18 +250,18 @@ mod tests {
             Some(Action::AttachHighlighted),
         );
         assert_eq!(
-            cfg.keymap.resolve(Mode::Normal, "s"),
+            cfg.keymap.resolve(Mode::Normal, "n"),
             Some(Action::OpenSpawnModal),
         );
         assert_eq!(
-            cfg.keymap.resolve(Mode::Normal, "S"),
+            cfg.keymap.resolve(Mode::Normal, "N"),
             Some(Action::FastForwardSpawn),
         );
     }
 
     /// AoE-style defaults (#shortcuts): `q` and `tab` are bare because Normal
     /// mode only exists while the sidebar is focused, so neither can leak
-    /// into a pty; `esc` is a second way out of Insert alongside the leader.
+    /// into a pty; `esc` stays unbound in Insert so it reaches the session.
     #[test]
     fn aoe_style_defaults_are_bound() {
         let cfg = TuiConfig::load(&TuiSection::default()).unwrap();
@@ -240,10 +270,7 @@ mod tests {
             cfg.keymap.resolve(Mode::Normal, "tab"),
             Some(Action::AttachHighlighted),
         );
-        assert_eq!(
-            cfg.keymap.resolve(Mode::Insert, "esc"),
-            Some(Action::LeaveInsert),
-        );
+        assert_eq!(cfg.keymap.resolve(Mode::Insert, "esc"), None);
     }
 
     #[test]
@@ -270,6 +297,60 @@ mod tests {
         assert_eq!(cfg.keymap.resolve(Mode::Insert, "ctrl-a"), None);
     }
 
+    /// The literal-Ctrl-K escape hatch (#156) is chorded off the default
+    /// leader, `ctrl-a ctrl-k` — not the command bar.
+    #[test]
+    fn default_leader_escapes_a_literal_ctrl_k() {
+        let cfg = TuiConfig::load(&TuiSection::default()).unwrap();
+        assert_eq!(
+            cfg.keymap.resolve(Mode::Insert, "ctrl-a ctrl-k"),
+            Some(Action::SendLiteralCtrlK),
+        );
+    }
+
+    /// Rebinding the leader must rebind the literal-Ctrl-K chord with it, not
+    /// just the Insert escape — proving the chord is built from the
+    /// configured leader rather than a hardcoded `ctrl-a`.
+    #[test]
+    fn rebinding_leader_moves_the_literal_ctrl_k_chord() {
+        let mut section = TuiSection::default();
+        section.leader = Some("ctrl-b".into());
+        let cfg = TuiConfig::load(&section).unwrap();
+        assert_eq!(
+            cfg.keymap.resolve(Mode::Insert, "ctrl-b ctrl-k"),
+            Some(Action::SendLiteralCtrlK),
+        );
+        // The old leader's chord is gone along with its Insert escape.
+        assert_eq!(cfg.keymap.resolve(Mode::Insert, "ctrl-a ctrl-k"), None);
+    }
+
+    /// The literal-leader escape hatch (#158) is chorded off the leader
+    /// doubled: `ctrl-a ctrl-a` — tmux's doubled-prefix resolution.
+    #[test]
+    fn default_leader_escapes_a_literal_leader() {
+        let cfg = TuiConfig::load(&TuiSection::default()).unwrap();
+        assert_eq!(
+            cfg.keymap.resolve(Mode::Insert, "ctrl-a ctrl-a"),
+            Some(Action::SendLiteralLeader),
+        );
+    }
+
+    /// Rebinding the leader must rebind the literal-leader chord with it,
+    /// not just the Insert escape and the Ctrl-K chord — proving it too is
+    /// built from the configured leader rather than a hardcoded `ctrl-a`.
+    #[test]
+    fn rebinding_leader_moves_the_literal_leader_chord() {
+        let mut section = TuiSection::default();
+        section.leader = Some("ctrl-b".into());
+        let cfg = TuiConfig::load(&section).unwrap();
+        assert_eq!(
+            cfg.keymap.resolve(Mode::Insert, "ctrl-b ctrl-b"),
+            Some(Action::SendLiteralLeader),
+        );
+        // The old leader's chord is gone along with the rest of its bindings.
+        assert_eq!(cfg.keymap.resolve(Mode::Insert, "ctrl-a ctrl-a"), None);
+    }
+
     #[test]
     fn user_normal_override_replaces_default() {
         let mut section = TuiSection::default();
@@ -311,18 +392,18 @@ mod tests {
         assert!(s.contains("ctrl-glorb"), "diagnostic: {s}");
     }
 
-    /// Regression for #70: the previous canonical form of a real Shift+S
-    /// keypress was `"shift-S"`, which the default `"S"` binding never
+    /// Regression for #70: the previous canonical form of a real Shift+N
+    /// keypress was `"shift-N"`, which the default `"N"` binding never
     /// matched. Drive the actual crossterm event, not the binding string,
     /// so the dead-key bug can't come back unnoticed.
     #[test]
-    fn real_shift_s_keypress_resolves_to_fast_forward_spawn() {
+    fn real_shift_n_keypress_resolves_to_fast_forward_spawn() {
         use crossterm::event::{Event as CtEvent, KeyCode, KeyEvent, KeyModifiers};
 
         use crate::input::{canonicalise, Region};
 
         let cfg = TuiConfig::load(&TuiSection::default()).unwrap();
-        let ev = CtEvent::Key(KeyEvent::new(KeyCode::Char('S'), KeyModifiers::SHIFT));
+        let ev = CtEvent::Key(KeyEvent::new(KeyCode::Char('N'), KeyModifiers::SHIFT));
         let key = canonicalise(&ev, |_, _| Region::Unknown).expect("key event canonicalises");
 
         assert_eq!(

crates/maestro-tui/src/daemon_link.rs

@@ -250,6 +250,7 @@ mod tests {
                 dirty: false,
             },
             instance: instance.into(),
+            leader: maestro_config::DEFAULT_LEADER.into(),
         }
     }
 

crates/maestro-tui/src/draft.rs

@@ -41,8 +41,10 @@ use std::time::{Duration, Instant};
 
 use chrono::{DateTime, Utc};
 use maestro_config::{builtin_presets, custom_preset};
-use maestro_protocol::display::abbreviate_dir;
-use maestro_protocol::{BranchInfo, CreateSessionRequest, Project, SpawnPreset, WorktreeSpec};
+use maestro_protocol::display::{abbreviate_dir, command_tool};
+use maestro_protocol::{
+    BranchInfo, CreateSessionRequest, Project, SessionView, SpawnPreset, WorktreeSpec,
+};
 use ratatui::layout::{Constraint, Layout, Rect};
 use ratatui::style::{Modifier, Style};
 use ratatui::text::{Line, Span};
@@ -86,9 +88,11 @@ pub enum DraftField {
     /// apply immediately, mirroring the web form's per-click choice.
     WorktreeChoice,
     Name,
-    /// Disclosure collapsing the worktree/branch controls below (#93).
+    /// Disclosure collapsing the optional view and worktree controls below.
     /// Closed by default; Enter / Space toggles.
     Advanced,
+    /// ACP-backed transcript instead of a terminal. Claude Code only.
+    StructuredToggle,
     /// Worktree on/off for this session (#65). Enter / Space toggles.
     WorktreeToggle,
     /// New-vs-existing branch source; Left / Right switches.
@@ -228,6 +232,10 @@ pub struct DraftPane {
     /// respawns there without touching the picker. Consumed by the first
     /// [`Self::set_projects`]; `None` once applied or when nothing seeded it.
     pub seed_cwd: Option<PathBuf>,
+    /// Command to preselect once the preset list lands — "spawn similar"'s
+    /// half of the clone (#155). Consumed by the first [`Self::set_presets`];
+    /// `None` once applied or when nothing seeded it.
+    pub seed_command: Option<String>,
     /// The repository picked in step one ([`group_key`] of its main box),
     /// `None` until a box is picked. Looked up fresh in `groups` rather than
     /// cached, so a project-list refresh can't leave it stale.
@@ -247,6 +255,9 @@ pub struct DraftPane {
     /// "Advanced options" disclosure (#93). Closed by default — most spawns
     /// take the default target.
     pub advanced_collapsed: bool,
+    /// ACP-backed structured transcript. Off by default and supported only
+    /// when the resolved command is Claude Code.
+    pub structured_view: bool,
     /// Enclosing repository of the chosen target — from the project scan for
     /// picked rows, `/api/gitroot` for raw paths. `None` until known.
     pub base_repo: Option<PathBuf>,
@@ -291,6 +302,7 @@ impl Default for DraftPane {
             id: NEXT_DRAFT_ID.fetch_add(1, std::sync::atomic::Ordering::Relaxed),
             presets,
             selected_preset: 0,
+            seed_command: None,
             custom_command: crate::text_input::TextInput::default(),
             groups: Vec::new(),
             filter: crate::text_input::TextInput::default(),
@@ -306,6 +318,7 @@ impl Default for DraftPane {
             name_touched: false,
             worktree_enabled: true,
             advanced_collapsed: true,
+            structured_view: false,
             base_repo: None,
             probed_cwd: None,
             probe_seq: 0,
@@ -342,6 +355,28 @@ impl DraftPane {
             .iter()
             .position(|p| !p.command.is_empty())
             .unwrap_or(0);
+        self.apply_seed_command();
+        self.clear_unsupported_structured_view();
+    }
+
+    /// Land a seeded command on the tile that runs it: its own preset when the
+    /// daemon offers one, otherwise the custom escape hatch with the command
+    /// typed in.
+    fn apply_seed_command(&mut self) {
+        let Some(command) = self.seed_command.take() else {
+            return;
+        };
+        match self.presets.iter().position(|p| p.command == command) {
+            Some(index) => self.selected_preset = index,
+            None => {
+                self.selected_preset = self
+                    .presets
+                    .iter()
+                    .position(|p| p.command.is_empty())
+                    .unwrap_or(self.selected_preset);
+                self.custom_command = crate::text_input::TextInput::with_value(command);
+            }
+        }
     }
 
     /// Replace the project snapshot: sort fresh-first (#54), group by
@@ -637,6 +672,22 @@ impl DraftPane {
         }
     }
 
+    fn supports_structured_view(&self) -> bool {
+        command_tool(self.command()) == Some("claude")
+    }
+
+    fn clear_unsupported_structured_view(&mut self) {
+        if !self.supports_structured_view() {
+            self.structured_view = false;
+        }
+    }
+
+    pub fn toggle_structured_view(&mut self) {
+        if self.supports_structured_view() {
+            self.structured_view = !self.structured_view;
+        }
+    }
+
     /// The chosen working directory: a picked project row, else the raw path
     /// input when it holds something.
     pub fn cwd(&self) -> Option<PathBuf> {
@@ -668,6 +719,11 @@ impl DraftPane {
         }
         let worktree = self.build_worktree()?;
         Ok(CreateSessionRequest {
+            view: if self.structured_view && self.supports_structured_view() {
+                SessionView::Structured
+            } else {
+                SessionView::Terminal
+            },
             cwd,
             command: command.to_string(),
             env: Default::default(),
@@ -727,6 +783,9 @@ impl DraftPane {
         order.push(DraftField::Name);
         order.push(DraftField::Advanced);
         if !self.advanced_collapsed {
+            if self.supports_structured_view() {
+                order.push(DraftField::StructuredToggle);
+            }
             if !self.cwd_raw_visible && self.selected_group_key.is_some() {
                 order.push(DraftField::WorktreeChoice);
             }
@@ -768,6 +827,7 @@ impl DraftPane {
         }
         self.selected_preset =
             ((self.selected_preset as i32) + delta).rem_euclid(len as i32) as usize;
+        self.clear_unsupported_structured_view();
     }
 
     /// Step-one boxes surviving the type-to-filter, in display order. A
@@ -974,9 +1034,9 @@ impl DraftPane {
             // Two fields keep their own Enter instead: `DirPicker`, whose
             // highlighted row isn't the picked one until a first Enter chooses
             // it (the next Enter, now that it's active, falls through to
-            // submit); and the disclosure/toggle pair (`Advanced`,
-            // `WorktreeToggle`), which activate on Enter like a button rather
-            // than submitting, same as the web form's own `<button>` controls.
+            // submit); and the disclosure/checkbox fields, which activate on
+            // Enter like buttons rather than submitting, matching the web
+            // form controls.
             InputKey::Enter if self.focused_field == DraftField::DirPicker => {
                 let is_other_row = self.selection() >= self.visible_groups().len();
                 let choose_only =
@@ -996,6 +1056,10 @@ impl DraftPane {
                 self.toggle_worktree();
                 DraftInputResult::Consumed
             }
+            InputKey::Enter if self.focused_field == DraftField::StructuredToggle => {
+                self.toggle_structured_view();
+                DraftInputResult::Consumed
+            }
             InputKey::Enter => DraftInputResult::Submit,
             InputKey::Char {
                 c: ' ',
@@ -1013,6 +1077,14 @@ impl DraftPane {
                 self.toggle_worktree();
                 DraftInputResult::Consumed
             }
+            InputKey::Char {
+                c: ' ',
+                ctrl: false,
+                ..
+            } if self.focused_field == DraftField::StructuredToggle => {
+                self.toggle_structured_view();
+                DraftInputResult::Consumed
+            }
             InputKey::Up if self.focused_field == DraftField::DirPicker => {
                 self.move_selection(-1);
                 DraftInputResult::Consumed
@@ -1056,7 +1128,10 @@ impl DraftPane {
             other => {
                 match self.focused_field {
                     DraftField::Preset | DraftField::Submit => {}
-                    DraftField::CustomCommand => self.custom_command.handle_key(other),
+                    DraftField::CustomCommand => {
+                        self.custom_command.handle_key(other);
+                        self.clear_unsupported_structured_view();
+                    }
                     // Typing filters the list; the highlight resets to the top
                     // so a narrowed search always starts at its best match.
                     DraftField::DirPicker => {
@@ -1094,9 +1169,9 @@ impl DraftPane {
 
         let show_custom = self.is_custom();
         let show_raw = self.cwd_raw_visible;
-        // The worktree choice step, the worktree toggle and its body all stay
-        // behind the "Advanced options" disclosure (#93): collapsed hides
-        // them, regardless of what they'd otherwise show.
+        let show_structured = !self.advanced_collapsed && self.supports_structured_view();
+        // Optional view and worktree controls stay behind the "Advanced
+        // options" disclosure (#93), regardless of what they'd otherwise show.
         let show_wt_toggle = !self.advanced_collapsed;
         let show_wt_body = show_wt_toggle && self.worktree_body_visible();
         let show_wt_choice =
@@ -1115,6 +1190,7 @@ impl DraftPane {
         let fixed: u16 = 3 /* tiles + dir + name */ + 1 /* advanced header */ + 1 /* spawn */
             + u16::from(show_custom)
             + u16::from(show_raw)
+            + u16::from(show_structured)
             + u16::from(show_wt_toggle)
             + u16::from(show_wt_choice) * wt_choice_capacity
             + u16::from(show_wt_body) * (1 + if self.branch_mode == WorktreeBranchMode::New { 1 } else { branch_rows })
@@ -1134,6 +1210,9 @@ impl DraftPane {
         }
         constraints.push(Constraint::Length(1)); // name
         constraints.push(Constraint::Length(1)); // advanced header
+        if show_structured {
+            constraints.push(Constraint::Length(1));
+        }
         if show_wt_choice {
             constraints.push(Constraint::Length(wt_choice_capacity));
         }
@@ -1332,6 +1411,24 @@ impl DraftPane {
             advanced_row,
         );
 
+        if show_structured {
+            let row = next_row();
+            f.render_widget(
+                Paragraph::new(Line::from(vec![
+                    Span::raw(format!("{:<GUTTER$}", "view:")),
+                    Span::styled(
+                        if self.structured_view {
+                            "[x] structured view"
+                        } else {
+                            "[ ] structured view"
+                        },
+                        field_style(DraftField::StructuredToggle),
+                    ),
+                ])),
+                row,
+            );
+        }
+
         if show_wt_choice {
             // Step two (#96 rule 3): "+ new" first, then the repository's
             // worktrees newest-first.
@@ -1688,6 +1785,48 @@ mod tests {
         assert_eq!(draft.presets.last().unwrap().id, "custom");
     }
 
+    /// "Spawn similar" (#155) seeds the cloned session's command: it lands on
+    /// the tile that runs it when the daemon offers one.
+    #[test]
+    fn a_seeded_command_selects_its_own_preset() {
+        let mut draft = DraftPane {
+            seed_command: Some("aider".into()),
+            ..DraftPane::default()
+        };
+        draft.set_presets(vec![
+            SpawnPreset {
+                id: "claude".into(),
+                label: "Claude".into(),
+                command: "claude".into(),
+            },
+            SpawnPreset {
+                id: "aider".into(),
+                label: "Aider".into(),
+                command: "aider".into(),
+            },
+        ]);
+        assert_eq!(draft.command(), "aider");
+        assert!(!draft.is_custom());
+        assert_eq!(draft.seed_command, None, "consumed by the first load");
+    }
+
+    /// A command no preset runs falls back to the custom tile with the command
+    /// typed in, so the clone still spawns what it cloned.
+    #[test]
+    fn a_seeded_command_with_no_preset_fills_the_custom_tile() {
+        let mut draft = DraftPane {
+            seed_command: Some("bash -l".into()),
+            ..DraftPane::default()
+        };
+        draft.set_presets(vec![SpawnPreset {
+            id: "claude".into(),
+            label: "Claude".into(),
+            command: "claude".into(),
+        }]);
+        assert!(draft.is_custom());
+        assert_eq!(draft.command(), "bash -l");
+    }
+
     #[test]
     fn left_right_cycles_presets_wrapping_into_custom() {
         let mut draft = DraftPane {
@@ -1748,6 +1887,45 @@ mod tests {
         assert_eq!(req.cwd, PathBuf::from("/srv/work"));
     }
 
+    #[test]
+    fn structured_view_is_default_off_and_only_visible_for_claude_code() {
+        let mut draft = DraftPane {
+            advanced_collapsed: false,
+            ..DraftPane::default()
+        };
+        assert!(!draft.structured_view);
+        assert!(draft.field_order().contains(&DraftField::StructuredToggle));
+        let rendered = render_to_string(100, 24, |f| draft.render(f, f.area(), true));
+        assert!(rendered.contains("[ ] structured view"), "{rendered}");
+
+        draft.toggle_structured_view();
+        assert!(draft.structured_view);
+        draft.cycle_preset(1);
+        assert_eq!(draft.command(), "opencode");
+        assert!(
+            !draft.structured_view,
+            "a hidden value must not stay checked"
+        );
+        assert!(!draft.field_order().contains(&DraftField::StructuredToggle));
+        let rendered = render_to_string(100, 24, |f| draft.render(f, f.area(), true));
+        assert!(!rendered.contains("structured view"), "{rendered}");
+    }
+
+    #[test]
+    fn structured_view_request_is_guarded_against_a_stale_command() {
+        let mut draft = DraftPane {
+            picked_cwd: Some(PathBuf::from("/srv/work")),
+            worktree_enabled: false,
+            structured_view: true,
+            ..DraftPane::default()
+        };
+        assert_eq!(draft.build_request().unwrap().view, SessionView::Structured);
+
+        draft.selected_preset = 1;
+        assert_eq!(draft.command(), "opencode");
+        assert_eq!(draft.build_request().unwrap().view, SessionView::Terminal);
+    }
+
     #[test]
     fn projects_render_sorted_with_stale_dimmed_and_other_directory_last() {
         let mut draft = DraftPane {

crates/maestro-tui/src/fast_forward.rs

@@ -49,6 +49,33 @@ pub fn resolve(
                 .into_iter()
                 .next()
         });
+    defaults(project, presets, handle)
+}
+
+/// Resolve the defaults for a spawn pinned to one directory — the command
+/// bar's `~` (#154), where the operator named the directory and nothing may
+/// override it. Unlike [`resolve`] there is no recency fallback: a directory
+/// the project scan does not know leaves `project` `None`, which is an
+/// unresolvable default, so the keystroke opens the pre-filled form instead of
+/// spawning somewhere else.
+pub fn resolve_at(
+    dir: &std::path::Path,
+    projects: &[Project],
+    presets: &[SpawnPreset],
+    handle: Option<String>,
+) -> FastForwardDefaults {
+    let project = projects.iter().find(|p| p.path == dir).cloned();
+    defaults(project, presets, handle)
+}
+
+/// The project's last command, or the first non-custom preset, wrapped up with
+/// the rest of the defaults. Shared by both resolvers so the two entry points
+/// can never settle on different commands.
+fn defaults(
+    project: Option<Project>,
+    presets: &[SpawnPreset],
+    handle: Option<String>,
+) -> FastForwardDefaults {
     let command = project
         .as_ref()
         .and_then(|p| p.last_command.clone())
@@ -81,6 +108,7 @@ impl FastForwardDefaults {
             return None;
         }
         Some(CreateSessionRequest {
+            view: Default::default(),
             cwd: project.path.clone(),
             command: command.to_string(),
             env: Default::default(),
@@ -159,6 +187,46 @@ mod tests {
         }
     }
 
+    /// The command bar's `~` names the directory; nothing may override it.
+    #[test]
+    fn resolve_at_pins_the_directory_over_the_recency_ranking() {
+        let projects = vec![
+            project("/repos/fresh", 0, Some("aider")),
+            project("/repos/pinned", 30, Some("zsh")),
+        ];
+        let resolved = resolve_at(
+            std::path::Path::new("/repos/pinned"),
+            &projects,
+            &[preset("claude", "claude")],
+            Some("otter".into()),
+        );
+        assert_eq!(
+            resolved.project.as_ref().map(|p| p.path.clone()),
+            Some(PathBuf::from("/repos/pinned"))
+        );
+        assert_eq!(resolved.command.as_deref(), Some("zsh"));
+        let req = resolved.build_request().expect("every default resolved");
+        assert_eq!(req.cwd, PathBuf::from("/repos/pinned"));
+    }
+
+    /// A directory the scan does not know resolves no project, so there is no
+    /// request to build — the caller opens the pre-filled form instead of
+    /// spawning somewhere else.
+    #[test]
+    fn resolve_at_takes_no_fallback_for_an_unknown_directory() {
+        let projects = vec![project("/repos/fresh", 0, Some("aider"))];
+        let resolved = resolve_at(
+            std::path::Path::new("/elsewhere"),
+            &projects,
+            &[preset("claude", "claude")],
+            Some("otter".into()),
+        );
+        assert_eq!(resolved.project, None);
+        // The preset still resolves; the missing project is what blocks it.
+        assert_eq!(resolved.command.as_deref(), Some("claude"));
+        assert_eq!(resolved.build_request(), None);
+    }
+
     #[test]
     fn resolves_every_default_from_the_most_recent_project() {
         let projects = vec![

crates/maestro-tui/src/input.rs

@@ -387,6 +387,9 @@ pub struct ChordState {
     held: Vec<String>,
     last_press: Option<Instant>,
     timeout: Duration,
+    /// A key bumped out of an abandoned chord (see [`Self::feed`]), waiting
+    /// to be replayed as a fresh keystroke by the caller.
+    replay: Option<InputKey>,
 }
 
 impl ChordState {
@@ -395,6 +398,7 @@ impl ChordState {
             held: Vec::new(),
             last_press: None,
             timeout,
+            replay: None,
         }
     }
 
@@ -404,6 +408,13 @@ impl ChordState {
     ///   binding; wait for the next key.
     /// * `Resolved(s)` — `s` is the canonical chord (or single key) to look
     ///   up in the keymap. The held buffer is cleared.
+    ///
+    /// A held prefix that is itself directly bound (e.g. a leader key bound
+    /// alone as well as chorded, like `ctrl-a` and `ctrl-a ctrl-k`) resolves
+    /// to that binding the moment the next key fails to extend it, rather
+    /// than swallowing the held key and losing its meaning — the new key
+    /// never belonged to the chord and is handed back via [`Self::take_replay`]
+    /// so the caller can process it as its own keystroke.
     pub fn feed(&mut self, key: &InputKey, known_bindings: &HashSet<String>) -> ChordResult {
         if let Some(t) = self.last_press {
             if t.elapsed() > self.timeout {
@@ -428,11 +439,31 @@ impl ChordState {
 
         if is_prefix {
             self.held.push(key_s);
-            ChordResult::Pending
-        } else {
-            self.held.clear();
-            ChordResult::Resolved(candidate)
+            return ChordResult::Pending;
         }
+
+        if known_bindings.contains(&candidate) {
+            self.held.clear();
+            return ChordResult::Resolved(candidate);
+        }
+
+        if !self.held.is_empty() {
+            let held_str = self.held.join(" ");
+            self.held.clear();
+            if known_bindings.contains(&held_str) {
+                self.replay = Some(key.clone());
+                return ChordResult::Resolved(held_str);
+            }
+        }
+
+        ChordResult::Resolved(candidate)
+    }
+
+    /// Take the key bumped out of an abandoned chord by the last [`Self::feed`]
+    /// call, if any. The caller feeds it through again as a brand new
+    /// keystroke.
+    pub fn take_replay(&mut self) -> Option<InputKey> {
+        self.replay.take()
     }
 }
 
@@ -597,7 +628,8 @@ mod tests {
     /// so a real Shift+S delivers `Char { c: 'S', shift: true }`. Its
     /// canonical form must be the bare `"S"` a keymap binds, not `"shift-S"` —
     /// the uppercase letter already says "shifted"; a redundant prefix would
-    /// make the default `S` binding unreachable from the keyboard (#70).
+    /// make every uppercase binding (the default `N`) unreachable from the
+    /// keyboard (#70).
     #[test]
     fn shift_flag_is_redundant_for_an_already_uppercase_char() {
         let k = InputKey::Char {
@@ -732,6 +764,41 @@ mod tests {
         assert_eq!(r, ChordResult::Resolved("g x".into()));
     }
 
+    /// A key bound both alone and as a chord prefix (the leader: `ctrl-a` and
+    /// `ctrl-a ctrl-k`) must still fire its own binding when the next key
+    /// doesn't complete the chord — the held key's meaning isn't lost, and
+    /// the new key comes back via `take_replay` for the caller to process on
+    /// its own (#156).
+    #[test]
+    fn a_bound_prefix_resolves_itself_and_replays_the_breaking_key() {
+        let mut chord = ChordState::new(Duration::from_secs(10));
+        let known: HashSet<String> = ["ctrl-a".into(), "ctrl-a ctrl-k".into()]
+            .into_iter()
+            .collect();
+
+        let r = chord.feed(&InputKey::ctrl_char('a'), &known);
+        assert_eq!(r, ChordResult::Pending);
+
+        let r = chord.feed(&InputKey::char('j'), &known);
+        assert_eq!(r, ChordResult::Resolved("ctrl-a".into()));
+        assert_eq!(chord.take_replay(), Some(InputKey::char('j')));
+    }
+
+    /// The full chord still resolves normally when the next key completes
+    /// it — no replay, no early fire of the shorter binding.
+    #[test]
+    fn a_completed_chord_off_a_bound_prefix_has_no_replay() {
+        let mut chord = ChordState::new(Duration::from_secs(10));
+        let known: HashSet<String> = ["ctrl-a".into(), "ctrl-a ctrl-k".into()]
+            .into_iter()
+            .collect();
+
+        chord.feed(&InputKey::ctrl_char('a'), &known);
+        let r = chord.feed(&InputKey::ctrl_char('k'), &known);
+        assert_eq!(r, ChordResult::Resolved("ctrl-a ctrl-k".into()));
+        assert_eq!(chord.take_replay(), None);
+    }
+
     #[test]
     fn chord_state_lone_key_resolves_immediately() {
         let mut chord = ChordState::new(Duration::from_secs(10));

crates/maestro-tui/src/lib.rs

@@ -6,6 +6,7 @@ pub mod action;
 pub mod app;
 pub mod catalog;
 pub mod cli;
+pub mod command_bar;
 pub mod config;
 pub mod daemon_link;
 pub mod draft;
@@ -13,6 +14,7 @@ pub mod emulators;
 pub mod fast_forward;
 pub mod input;
 pub mod keymap;
+pub mod matcher;
 pub mod overlays;
 pub mod palette;
 pub mod pane;
@@ -21,6 +23,8 @@ pub mod render;
 pub mod session_task;
 pub mod sidebar;
 pub mod state;
+pub mod structured_pane;
+pub mod structured_task;
 pub mod terminal;
 pub mod text_input;
 

crates/maestro-tui/src/matcher.rs

@@ -0,0 +1,750 @@
+//! Pure match-and-rank function for the `ctrl-k` command bar.
+//!
+//! Implements exactly the algorithm in `docs/COMMAND-BAR.md` ("What a
+//! candidate is", "Match and rank", "Fixtures"). Must produce the same order
+//! and scores as `web/src/matcher.ts` for the same input.
+
+use std::collections::HashMap;
+
+#[derive(Debug, Clone, Copy, PartialEq, Eq)]
+pub enum CandidateKind {
+    Session,
+    Command,
+    Directory,
+}
+
+#[derive(Debug, Clone, Copy, PartialEq, Eq, Hash)]
+pub enum MatchFieldName {
+    Name,
+    Directory,
+    Command,
+    Tool,
+    Label,
+    Path,
+}
+
+#[derive(Debug, Clone, PartialEq, Eq)]
+pub struct SessionCandidate {
+    pub name: String,
+    pub directory: Option<String>,
+    pub command: Option<String>,
+    pub tool: Option<String>,
+}
+
+#[derive(Debug, Clone, PartialEq, Eq)]
+pub struct CommandCandidate {
+    pub label: String,
+}
+
+#[derive(Debug, Clone, PartialEq, Eq)]
+pub struct DirectoryCandidate {
+    pub path: String,
+}
+
+#[derive(Debug, Clone, PartialEq, Eq)]
+pub enum MatchCandidate {
+    Session(SessionCandidate),
+    Command(CommandCandidate),
+    Directory(DirectoryCandidate),
+}
+
+pub type MatchRange = (usize, usize);
+
+#[derive(Debug, PartialEq, Eq)]
+pub struct MatchResult<'c> {
+    pub candidate: &'c MatchCandidate,
+    pub score: i32,
+    pub field: Option<MatchFieldName>,
+    pub ranges: Vec<MatchRange>,
+}
+
+struct Field<'c> {
+    name: MatchFieldName,
+    text: &'c str,
+    weight: i32,
+}
+
+impl MatchCandidate {
+    fn kind(&self) -> CandidateKind {
+        match self {
+            MatchCandidate::Session(_) => CandidateKind::Session,
+            MatchCandidate::Command(_) => CandidateKind::Command,
+            MatchCandidate::Directory(_) => CandidateKind::Directory,
+        }
+    }
+
+    fn fields(&self) -> Vec<Field<'_>> {
+        match self {
+            MatchCandidate::Session(session) => {
+                let mut fields = vec![Field {
+                    name: MatchFieldName::Name,
+                    text: &session.name,
+                    weight: 0,
+                }];
+                if let Some(directory) = &session.directory {
+                    fields.push(Field {
+                        name: MatchFieldName::Directory,
+                        text: directory,
+                        weight: -24,
+                    });
+                }
+                if let Some(command) = &session.command {
+                    fields.push(Field {
+                        name: MatchFieldName::Command,
+                        text: command,
+                        weight: -32,
+                    });
+                }
+                if let Some(tool) = &session.tool {
+                    fields.push(Field {
+                        name: MatchFieldName::Tool,
+                        text: tool,
+                        weight: -40,
+                    });
+                }
+                fields
+            }
+            MatchCandidate::Command(command) => vec![Field {
+                name: MatchFieldName::Label,
+                text: &command.label,
+                weight: 0,
+            }],
+            MatchCandidate::Directory(directory) => vec![Field {
+                name: MatchFieldName::Path,
+                text: &directory.path,
+                weight: 0,
+            }],
+        }
+    }
+}
+
+fn kind_order(kind: CandidateKind) -> u8 {
+    match kind {
+        CandidateKind::Session => 0,
+        CandidateKind::Command => 1,
+        CandidateKind::Directory => 2,
+    }
+}
+
+fn lower_char(c: char) -> char {
+    c.to_lowercase().next().unwrap_or(c)
+}
+
+fn lower_chars(chars: &[char]) -> Vec<char> {
+    chars.iter().copied().map(lower_char).collect()
+}
+
+fn normalize_query(query: &str) -> Vec<char> {
+    query
+        .chars()
+        .filter(|c| !c.is_whitespace())
+        .map(lower_char)
+        .collect()
+}
+
+const SEPARATORS: [char; 6] = ['/', '\\', '-', '_', '.', ':'];
+
+fn boundary_bonus(text: &[char], position: usize) -> i32 {
+    if position == 0 {
+        return 18;
+    }
+
+    let previous = text[position - 1];
+    if previous == ' ' || SEPARATORS.contains(&previous) {
+        return 16;
+    }
+
+    let current = text[position];
+    if current.is_uppercase() && previous.is_lowercase() {
+        return 12;
+    }
+
+    let is_digit = current.is_ascii_digit();
+    let previous_is_digit = previous.is_ascii_digit();
+    if is_digit && !previous_is_digit {
+        return 12;
+    }
+
+    0
+}
+
+fn contribution(text: &[char], position: usize, previous_position: isize) -> i32 {
+    let gap = position as isize - previous_position - 1;
+    16 + boundary_bonus(text, position) + if gap == 0 { 8 } else { -gap.min(12) as i32 }
+}
+
+#[derive(Clone)]
+struct Embedding {
+    score: i32,
+    positions: Vec<usize>,
+}
+
+fn is_better_embedding(candidate: &Embedding, incumbent: Option<&Embedding>) -> bool {
+    let Some(incumbent) = incumbent else {
+        return true;
+    };
+    if candidate.score != incumbent.score {
+        return candidate.score > incumbent.score;
+    }
+    for (c, i) in candidate.positions.iter().zip(incumbent.positions.iter()) {
+        if c != i {
+            return c < i;
+        }
+    }
+    false
+}
+
+/// The dynamic program over `(query index, text position)` described in
+/// "Which embedding": greedy leftmost-first matching is insufficient (e.g.
+/// `mtu` against `maestro-tui`), so every reachable position at each query
+/// index carries its best score and position vector forward.
+fn best_embedding(query: &[char], text: &[char]) -> Option<Embedding> {
+    let lower_text = lower_chars(text);
+    let mut previous_states: HashMap<usize, Embedding> = HashMap::new();
+
+    for (query_index, &qc) in query.iter().enumerate() {
+        let mut states: HashMap<usize, Embedding> = HashMap::new();
+
+        for (position, &text_char) in lower_text.iter().enumerate() {
+            if text_char != qc {
+                continue;
+            }
+
+            if query_index == 0 {
+                states.insert(
+                    position,
+                    Embedding {
+                        score: contribution(text, position, -1),
+                        positions: vec![position],
+                    },
+                );
+                continue;
+            }
+
+            for (&previous_position, previous) in previous_states.iter() {
+                if previous_position >= position {
+                    continue;
+                }
+                let mut positions = previous.positions.clone();
+                positions.push(position);
+                let candidate = Embedding {
+                    score: previous.score
+                        + contribution(text, position, previous_position as isize),
+                    positions,
+                };
+                if is_better_embedding(&candidate, states.get(&position)) {
+                    states.insert(position, candidate);
+                }
+            }
+        }
+
+        if states.is_empty() {
+            return None;
+        }
+        previous_states = states;
+    }
+
+    let mut best: Option<Embedding> = None;
+    for embedding in previous_states.into_values() {
+        if is_better_embedding(&embedding, best.as_ref()) {
+            best = Some(embedding);
+        }
+    }
+    best
+}
+
+fn to_ranges(positions: &[usize]) -> Vec<MatchRange> {
+    let mut ranges: Vec<MatchRange> = Vec::new();
+    for &position in positions {
+        if let Some(last) = ranges.last_mut() {
+            if last.1 == position {
+                last.1 = position + 1;
+                continue;
+            }
+        }
+        ranges.push((position, position + 1));
+    }
+    ranges
+}
+
+fn compact(text: &str) -> String {
+    text.chars()
+        .filter(|c| !c.is_whitespace())
+        .map(lower_char)
+        .collect()
+}
+
+struct Ranked<'c> {
+    candidate: &'c MatchCandidate,
+    score: i32,
+    field: Option<MatchFieldName>,
+    ranges: Vec<MatchRange>,
+    matched_text: String,
+    input_index: usize,
+}
+
+/// `(query, candidates) -> ranked subset with matched ranges`. Knows nothing
+/// about sessions, panes or the network — see docs/COMMAND-BAR.md.
+pub fn match_and_rank<'c>(query: &str, candidates: &'c [MatchCandidate]) -> Vec<MatchResult<'c>> {
+    let normalized_query = normalize_query(query);
+
+    if normalized_query.is_empty() {
+        return candidates
+            .iter()
+            .map(|candidate| MatchResult {
+                candidate,
+                score: 0,
+                field: None,
+                ranges: Vec::new(),
+            })
+            .collect();
+    }
+
+    let mut results: Vec<Ranked<'c>> = Vec::new();
+
+    for (input_index, candidate) in candidates.iter().enumerate() {
+        let mut best: Option<(MatchFieldName, &str, i32, Vec<usize>)> = None;
+
+        for field in candidate.fields() {
+            let text_chars: Vec<char> = field.text.chars().collect();
+            let Some(embedding) = best_embedding(&normalized_query, &text_chars) else {
+                continue;
+            };
+
+            let compact_text = compact(field.text);
+            let normalized_query_str: String = normalized_query.iter().collect();
+            let adjustment = if compact_text == normalized_query_str {
+                64
+            } else if compact_text.starts_with(&normalized_query_str) {
+                32
+            } else {
+                0
+            };
+            let score = embedding.score + adjustment + field.weight;
+
+            let is_better = match &best {
+                None => true,
+                Some((_, _, best_score, _)) => score > *best_score,
+            };
+            if is_better {
+                best = Some((field.name, field.text, score, embedding.positions));
+            }
+        }
+
+        if let Some((field_name, field_text, score, positions)) = best {
+            results.push(Ranked {
+                candidate,
+                score,
+                field: Some(field_name),
+                ranges: to_ranges(&positions),
+                matched_text: field_text.to_string(),
+                input_index,
+            });
+        }
+    }
+
+    results.sort_by(|a, b| {
+        b.score
+            .cmp(&a.score)
+            .then_with(|| kind_order(a.candidate.kind()).cmp(&kind_order(b.candidate.kind())))
+            .then_with(|| {
+                a.matched_text
+                    .chars()
+                    .count()
+                    .cmp(&b.matched_text.chars().count())
+            })
+            .then_with(|| a.matched_text.cmp(&b.matched_text))
+            .then_with(|| a.input_index.cmp(&b.input_index))
+    });
+
+    results
+        .into_iter()
+        .map(|ranked| MatchResult {
+            candidate: ranked.candidate,
+            score: ranked.score,
+            field: ranked.field,
+            ranges: ranked.ranges,
+        })
+        .collect()
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    fn session(
+        name: &str,
+        directory: Option<&str>,
+        command: Option<&str>,
+        tool: Option<&str>,
+    ) -> MatchCandidate {
+        MatchCandidate::Session(SessionCandidate {
+            name: name.to_string(),
+            directory: directory.map(str::to_string),
+            command: command.map(str::to_string),
+            tool: tool.map(str::to_string),
+        })
+    }
+
+    fn command(label: &str) -> MatchCandidate {
+        MatchCandidate::Command(CommandCandidate {
+            label: label.to_string(),
+        })
+    }
+
+    fn directory(path: &str) -> MatchCandidate {
+        MatchCandidate::Directory(DirectoryCandidate {
+            path: path.to_string(),
+        })
+    }
+
+    fn label(candidate: &MatchCandidate) -> String {
+        match candidate {
+            MatchCandidate::Session(s) => format!("session:{}", s.name),
+            MatchCandidate::Command(c) => format!("command:{}", c.label),
+            MatchCandidate::Directory(d) => format!("directory:{}", d.path),
+        }
+    }
+
+    fn positions(result: &MatchResult) -> Vec<usize> {
+        result
+            .ranges
+            .iter()
+            .flat_map(|&(start, end)| start..end)
+            .collect()
+    }
+
+    #[allow(clippy::type_complexity)]
+    fn expect_results(
+        query: &str,
+        candidates: &[MatchCandidate],
+        expected: &[(&str, i32, Option<MatchFieldName>, &[usize])],
+    ) {
+        let results = match_and_rank(query, candidates);
+
+        let actual: Vec<(String, i32)> = results
+            .iter()
+            .map(|r| (label(r.candidate), r.score))
+            .collect();
+        let expected_labels: Vec<(String, i32)> = expected
+            .iter()
+            .map(|(l, s, _, _)| (l.to_string(), *s))
+            .collect();
+        assert_eq!(actual, expected_labels, "order/scores for query {query:?}");
+
+        let actual_fields: Vec<Option<MatchFieldName>> = results.iter().map(|r| r.field).collect();
+        let expected_fields: Vec<Option<MatchFieldName>> =
+            expected.iter().map(|(_, _, f, _)| *f).collect();
+        assert_eq!(actual_fields, expected_fields, "fields for query {query:?}");
+
+        let actual_positions: Vec<Vec<usize>> = results.iter().map(positions).collect();
+        let expected_positions: Vec<Vec<usize>> =
+            expected.iter().map(|(_, _, _, p)| p.to_vec()).collect();
+        assert_eq!(
+            actual_positions, expected_positions,
+            "positions for query {query:?}"
+        );
+    }
+
+    #[test]
+    fn f1_empty_query_keeps_input_order() {
+        expect_results(
+            "",
+            &[
+                session("kill", Some("~/dev/api"), Some("bash"), None),
+                session(
+                    "killer-app",
+                    Some("~/dev/killer-app"),
+                    Some("claude --resume"),
+                    Some("claude"),
+                ),
+                command("Kill selected session"),
+            ],
+            &[
+                ("session:kill", 0, None, &[]),
+                ("session:killer-app", 0, None, &[]),
+                ("command:Kill selected session", 0, None, &[]),
+            ],
+        );
+    }
+
+    #[test]
+    fn f2_exact_session_name_beats_prefix_kind_breaks_tie() {
+        expect_results(
+            "kill",
+            &[
+                session("kill", Some("~/dev/api"), Some("bash"), None),
+                session(
+                    "killer-app",
+                    Some("~/dev/killer-app"),
+                    Some("claude --resume"),
+                    Some("claude"),
+                ),
+                command("Kill selected session"),
+            ],
+            &[
+                (
+                    "session:kill",
+                    178,
+                    Some(MatchFieldName::Name),
+                    &[0, 1, 2, 3],
+                ),
+                (
+                    "session:killer-app",
+                    146,
+                    Some(MatchFieldName::Name),
+                    &[0, 1, 2, 3],
+                ),
+                (
+                    "command:Kill selected session",
+                    146,
+                    Some(MatchFieldName::Label),
+                    &[0, 1, 2, 3],
+                ),
+            ],
+        );
+    }
+
+    #[test]
+    fn f3_path_segment_boundaries_beat_mid_segment() {
+        expect_results(
+            "foo",
+            &[
+                directory("~/dev/foobar"),
+                directory("~/src/myfoo"),
+                directory("~/foo"),
+            ],
+            &[
+                (
+                    "directory:~/foo",
+                    78,
+                    Some(MatchFieldName::Path),
+                    &[2, 3, 4],
+                ),
+                (
+                    "directory:~/dev/foobar",
+                    74,
+                    Some(MatchFieldName::Path),
+                    &[6, 7, 8],
+                ),
+                (
+                    "directory:~/src/myfoo",
+                    56,
+                    Some(MatchFieldName::Path),
+                    &[8, 9, 10],
+                ),
+            ],
+        );
+    }
+
+    #[test]
+    fn f4_no_match_returns_empty() {
+        expect_results(
+            "zzz",
+            &[
+                session("kill", Some("~/dev/api"), Some("bash"), None),
+                command("Kill selected session"),
+            ],
+            &[],
+        );
+    }
+
+    #[test]
+    fn f5_highest_scoring_embedding_beats_greedy() {
+        expect_results(
+            "mtu",
+            &[
+                session("maestro-tui", None, None, None),
+                session("maestro-daemon", None, None, None),
+                session("mtui-scratch", None, None, None),
+            ],
+            &[
+                (
+                    "session:mtui-scratch",
+                    122,
+                    Some(MatchFieldName::Name),
+                    &[0, 1, 2],
+                ),
+                (
+                    "session:maestro-tui",
+                    91,
+                    Some(MatchFieldName::Name),
+                    &[0, 8, 9],
+                ),
+            ],
+        );
+    }
+
+    #[test]
+    fn f6_name_beats_weighted_directory() {
+        expect_results(
+            "api",
+            &[
+                session("api", Some("~/dev/web"), Some("bash"), None),
+                session("worker", Some("~/dev/api"), Some("bash"), None),
+            ],
+            &[
+                ("session:api", 154, Some(MatchFieldName::Name), &[0, 1, 2]),
+                (
+                    "session:worker",
+                    50,
+                    Some(MatchFieldName::Directory),
+                    &[6, 7, 8],
+                ),
+            ],
+        );
+    }
+
+    #[test]
+    fn f7_case_insensitive_length_breaks_tie() {
+        expect_results(
+            "api",
+            &[
+                session("API-Gateway", None, None, None),
+                session("apiary", None, None, None),
+            ],
+            &[
+                (
+                    "session:apiary",
+                    122,
+                    Some(MatchFieldName::Name),
+                    &[0, 1, 2],
+                ),
+                (
+                    "session:API-Gateway",
+                    122,
+                    Some(MatchFieldName::Name),
+                    &[0, 1, 2],
+                ),
+            ],
+        );
+    }
+
+    #[test]
+    fn f8_exact_tool_beats_command_field() {
+        expect_results(
+            "claude",
+            &[
+                session(
+                    "nameless",
+                    Some("~/dev/x"),
+                    Some("claude --resume"),
+                    Some("claude"),
+                ),
+                session("clay", Some("~/dev/y"), Some("bash"), None),
+            ],
+            &[(
+                "session:nameless",
+                186,
+                Some(MatchFieldName::Tool),
+                &[0, 1, 2, 3, 4, 5],
+            )],
+        );
+    }
+
+    #[test]
+    fn f9_separator_earns_word_boundary_bonus() {
+        expect_results(
+            "ws",
+            &[
+                session("websearch", None, None, None),
+                session("web-search", None, None, None),
+            ],
+            &[
+                (
+                    "session:web-search",
+                    71,
+                    Some(MatchFieldName::Name),
+                    &[0, 4],
+                ),
+                ("session:websearch", 56, Some(MatchFieldName::Name), &[0, 3]),
+            ],
+        );
+    }
+
+    #[test]
+    fn f10_command_labels_rank_by_boundary_and_gap() {
+        expect_results(
+            "se",
+            &[
+                command("Kill selected session"),
+                command("Create a session"),
+                command("Show help"),
+            ],
+            &[
+                (
+                    "command:Show help",
+                    53,
+                    Some(MatchFieldName::Label),
+                    &[0, 6],
+                ),
+                (
+                    "command:Kill selected session",
+                    51,
+                    Some(MatchFieldName::Label),
+                    &[5, 6],
+                ),
+                (
+                    "command:Create a session",
+                    47,
+                    Some(MatchFieldName::Label),
+                    &[9, 10],
+                ),
+            ],
+        );
+    }
+
+    #[test]
+    fn f11_directory_matches_separate_on_initial_gap() {
+        expect_results(
+            "dev",
+            &[
+                session("api", Some("~/dev/api"), Some("bash"), None),
+                session("notes", Some("~/documents/dev-notes"), Some("nvim"), None),
+                session("scratch", Some("~/srv/devops"), Some("bash"), None),
+            ],
+            &[
+                (
+                    "session:api",
+                    54,
+                    Some(MatchFieldName::Directory),
+                    &[2, 3, 4],
+                ),
+                (
+                    "session:scratch",
+                    50,
+                    Some(MatchFieldName::Directory),
+                    &[6, 7, 8],
+                ),
+                (
+                    "session:notes",
+                    44,
+                    Some(MatchFieldName::Directory),
+                    &[12, 13, 14],
+                ),
+            ],
+        );
+    }
+
+    #[test]
+    fn f12_exact_beats_prefix() {
+        expect_results(
+            "quit",
+            &[command("Quit Maestro"), command("Quit")],
+            &[
+                (
+                    "command:Quit",
+                    178,
+                    Some(MatchFieldName::Label),
+                    &[0, 1, 2, 3],
+                ),
+                (
+                    "command:Quit Maestro",
+                    146,
+                    Some(MatchFieldName::Label),
+                    &[0, 1, 2, 3],
+                ),
+            ],
+        );
+    }
+}

crates/maestro-tui/src/palette.rs

@@ -813,6 +813,21 @@ impl Palette {
         }
     }
 
+    /// Background for the card whose session the pane is showing
+    /// (`docs/SIDEBAR.md`). It sits partway from the card surface to the
+    /// selection surface, so the sidebar reads as one ladder: unfilled, half
+    /// filled for the session in the pane, fully filled under the cursor.
+    ///
+    /// Blended rather than added as a third `Surface` — a new surface means
+    /// eight more colours hand-picked seventeen times — which is also why it
+    /// borrows the *selection* surface's foregrounds: those are the ones
+    /// already picked for a filled row. A preset whose colours the terminal
+    /// owns (`ansi`) has nothing to blend, so it keeps the card background and
+    /// says "in the pane" with the filled glyph alone.
+    pub fn pane_row_bg(&self) -> Color {
+        mix(self.card.bg, self.selection.bg, 0.55)
+    }
+
     /// Border style for a panel, by whether it holds focus.
     pub fn border_style(&self, focused: bool) -> Style {
         if focused {
@@ -873,6 +888,16 @@ pub fn active() -> Palette {
     *active_slot().read().expect("active palette lock poisoned")
 }
 
+/// Blend `amount` of `to` into `from`, in plain sRGB. Both must be RGB, or
+/// there is nothing to blend and `from` comes back unchanged.
+fn mix(from: Color, to: Color, amount: f64) -> Color {
+    let (Color::Rgb(fr, fg, fb), Color::Rgb(tr, tg, tb)) = (from, to) else {
+        return from;
+    };
+    let lerp = |a: u8, b: u8| (a as f64 + (b as f64 - a as f64) * amount).round() as u8;
+    Color::Rgb(lerp(fr, tr), lerp(fg, tg), lerp(fb, tb))
+}
+
 /// WCAG relative luminance of an RGB role. Non-RGB colours have no fixed
 /// luminance — they are whatever the terminal theme says — so they return
 /// `None` and cannot be contrast-checked.
@@ -937,6 +962,43 @@ mod tests {
         }
     }
 
+    /// The pane row is the middle rung: a visible fill against the card, still
+    /// a different surface from the cursor's, and carrying the selection
+    /// surface's foregrounds, which it borrows rather than shipping its own.
+    #[test]
+    fn the_pane_row_is_a_rung_between_the_card_and_the_selection() {
+        for (preset, p) in rgb_presets() {
+            let bg = p.pane_row_bg();
+            let from_card = contrast_ratio(p.card.bg, bg)
+                .unwrap_or_else(|| panic!("{preset}.pane_row_bg must be RGB"));
+            assert!(
+                from_card >= 1.15,
+                "{preset}: pane row {from_card:.2} from the card background is not a visible fill"
+            );
+            let from_selection =
+                contrast_ratio(p.selection.bg, bg).expect("selection.bg must be RGB");
+            assert!(
+                from_selection >= 1.15,
+                "{preset}: pane row {from_selection:.2} from the cursor's fill —                  the highlight would vanish on the session already in the pane"
+            );
+            for (role, color) in p.selection.roles() {
+                let ratio = contrast_ratio(bg, color).expect("selection role must be RGB");
+                let floor = if role == "dim" { 3.0 } else { 4.5 };
+                assert!(
+                    ratio >= floor,
+                    "{preset}.selection.{role} on the pane row is {ratio:.2}, below {floor}"
+                );
+            }
+        }
+    }
+
+    /// A preset the terminal themes has nothing to blend from.
+    #[test]
+    fn ansi_keeps_the_card_background_for_the_pane_row() {
+        let p = Palette::ANSI;
+        assert_eq!(p.pane_row_bg(), p.card.bg);
+    }
+
     #[test]
     fn every_preset_supplies_every_role() {
         for (name, p) in Palette::presets() {

crates/maestro-tui/src/render.rs

@@ -18,6 +18,7 @@ use crate::palette;
 use crate::pane::Pane;
 use crate::sidebar::Sidebar;
 use crate::state::{AppState, Focus, OverlayKind, SidebarItem};
+use crate::structured_pane::StructuredPane;
 
 /// Tagged regions for mouse hit-testing. The input router resolves a mouse
 /// coordinate to one of these via [`RegionMap::region_at`].
@@ -80,12 +81,16 @@ pub struct RenderInputs<'a> {
     pub home_dir: &'a str,
     pub pane_title: &'a str,
     pub pane: Option<&'a Pane>,
+    pub structured_pane: Option<&'a StructuredPane>,
     /// The spawn form behind [`OverlayKind::Spawn`], when one is up.
     pub draft: Option<&'a crate::draft::DraftPane>,
     pub state: &'a AppState,
     pub help: &'a HelpOverlay,
     /// Edit buffer behind the rename prompt (#125).
     pub rename_input: &'a crate::text_input::TextInput,
+    /// The command bar behind [`OverlayKind::CommandBar`] (#153), when one is
+    /// up.
+    pub command_bar: Option<&'a crate::command_bar::CommandBar>,
     /// Liveness + release of the daemon, for the status bar's indicator and the
     /// restart overlay (`docs/RESTART.md`).
     pub link: &'a crate::daemon_link::LinkStatus,
@@ -144,14 +149,22 @@ pub fn draw(f: &mut Frame, inputs: RenderInputs<'_>) -> RegionMap {
     render_title_bar(f, title_area, inputs.pane_title, pane_focused);
     if let Some(p) = inputs.pane {
         p.render(f, pane_area);
+    } else if let Some(p) = inputs.structured_pane {
+        p.render(f, pane_area);
     }
     // `RegionMap::pane` is also the PTY resize source. The title bar is
-    // chrome; every remaining cell belongs to the emulator.
+    // chrome; every remaining cell belongs to the active session pane.
     map.pane = Some(pane_area);
 
     // Status bar — always visible, never eclipsed by overlays so the user can
     // always see the current mode + key hints.
-    render_status_bar(f, status_area, inputs.state, inputs.link);
+    render_status_bar(
+        f,
+        status_area,
+        inputs.state,
+        inputs.link,
+        inputs.structured_pane.is_some(),
+    );
 
     match inputs.state.overlay() {
         Some(OverlayKind::Spawn) => {
@@ -198,6 +211,14 @@ pub fn draw(f: &mut Frame, inputs: RenderInputs<'_>) -> RegionMap {
             }
             map.modal = Some(area);
         }
+        Some(OverlayKind::CommandBar) => {
+            if let Some(bar) = inputs.command_bar {
+                if let Some((x, y)) = bar.render(f, area) {
+                    f.set_cursor_position((x, y));
+                }
+                map.modal = Some(area);
+            }
+        }
         Some(OverlayKind::Help) => {
             inputs.help.render(f, area);
             map.modal = Some(area);
@@ -242,7 +263,13 @@ fn render_title_bar(f: &mut Frame, area: Rect, title: &str, focused: bool) {
 /// Render the always-visible status bar at the bottom of the frame. Surfaces
 /// mode + focused panel + the most useful key hints so the user is never
 /// guessing what state they're in.
-fn render_status_bar(f: &mut Frame, area: Rect, state: &AppState, link: &LinkStatus) {
+fn render_status_bar(
+    f: &mut Frame,
+    area: Rect,
+    state: &AppState,
+    link: &LinkStatus,
+    structured: bool,
+) {
     // The daemon indicator is pinned right and sized to its own text, so a
     // narrow terminal truncates the key hints rather than the release.
     let label = link_label(link);
@@ -260,9 +287,13 @@ fn render_status_bar(f: &mut Frame, area: Rect, state: &AppState, link: &LinkSta
         Focus::Sidebar => "sidebar",
         Focus::Pane => "pane",
     };
-    let hint = match state.mode {
-        Mode::Normal => "j/k: nav  •  enter: attach  •  s: spawn  •  ?: help  •  ^Wq: quit",
-        Mode::Insert => "^a: return to sidebar",
+    let hint = match (structured && state.focus == Focus::Pane, state.mode) {
+        (true, Mode::Normal) => "j/k: rows  •  enter: expand  •  i: compose  •  esc: cancel",
+        (true, Mode::Insert) => "enter: send  •  esc: cancel  •  ^a: sidebar",
+        (false, Mode::Normal) => {
+            "j/k: nav  •  enter: attach  •  s: spawn  •  ?: help  •  ^Wq: quit"
+        }
+        (false, Mode::Insert) => "^a: return to sidebar",
     };
     let mode_style = palette::active().mode_style(state.mode == Mode::Insert);
     let line = ratatui::text::Line::from(vec![
@@ -415,6 +446,7 @@ mod tests {
             sessions: Vec::new(),
             highlight: None,
             attached: HashSet::new(),
+            pane_session: None,
         };
         let help = HelpOverlay { lines: Vec::new() };
         let state = AppState::new();
@@ -423,10 +455,12 @@ mod tests {
             home_dir: "",
             pane_title: "session",
             pane: None,
+            structured_pane: None,
             draft: None,
             state: &state,
             help: &help,
             rename_input: &crate::text_input::TextInput::default(),
+            command_bar: None,
             link,
         };
         let backend = ratatui::backend::TestBackend::new(120, 24);
@@ -511,6 +545,7 @@ mod tests {
             sessions: Vec::new(),
             highlight: None,
             attached: HashSet::new(),
+            pane_session: None,
         };
         let help = HelpOverlay { lines: Vec::new() };
         let inputs = RenderInputs {
@@ -518,10 +553,12 @@ mod tests {
             home_dir: "",
             pane_title: "session",
             pane: None,
+            structured_pane: None,
             draft: Some(&draft),
             state: &state,
             help: &help,
             rename_input: &crate::text_input::TextInput::default(),
+            command_bar: None,
             link: &online_link(),
         };
 
@@ -561,6 +598,7 @@ mod tests {
             sessions: Vec::new(),
             highlight: None,
             attached: HashSet::new(),
+            pane_session: None,
         };
         let help = HelpOverlay { lines: Vec::new() };
         let draw_map = |focus| {
@@ -571,10 +609,12 @@ mod tests {
                 home_dir: "",
                 pane_title: "session",
                 pane: None,
+                structured_pane: None,
                 draft: None,
                 state: &state,
                 help: &help,
                 rename_input: &crate::text_input::TextInput::default(),
+                command_bar: None,
                 link: &online_link(),
             };
             let backend = ratatui::backend::TestBackend::new(80, 24);
@@ -601,6 +641,7 @@ mod tests {
             sessions: Vec::new(),
             highlight: None,
             attached: HashSet::new(),
+            pane_session: None,
         };
         let help = HelpOverlay { lines: Vec::new() };
         let render = |focus| {
@@ -611,10 +652,12 @@ mod tests {
                 home_dir: "",
                 pane_title: "session",
                 pane: None,
+                structured_pane: None,
                 draft: None,
                 state: &state,
                 help: &help,
                 rename_input: &crate::text_input::TextInput::default(),
+                command_bar: None,
                 link: &online_link(),
             };
             let backend = ratatui::backend::TestBackend::new(80, 24);

crates/maestro-tui/src/session_task.rs

@@ -221,7 +221,7 @@ impl SessionTask {
     }
 }
 
-fn jitter(base: Duration) -> Duration {
+pub(crate) fn jitter(base: Duration) -> Duration {
     let ms = base.as_millis() as u64;
     let now_nanos = std::time::SystemTime::now()
         .duration_since(std::time::UNIX_EPOCH)

crates/maestro-tui/src/sidebar.rs

@@ -37,14 +37,39 @@ const META_INDENT: &str = "    ";
 /// both card rows, replacing the old inline dot glyph on the meta line.
 const RAIL: &str = "▌";
 
-/// Cards use the selection surface only while the sidebar owns focus. An
+/// Which fill a session card wears (docs/SIDEBAR.md). The cursor's fill wins
+/// on its own row: a highlight that lands on the session already in the pane
+/// still has to be visible.
+#[derive(Debug, Clone, Copy, PartialEq, Eq)]
+enum CardFill {
+    /// An ordinary card, on the card surface.
+    None,
+    /// The session the pane is showing.
+    Pane,
+    /// Under the cursor, with the sidebar holding the keyboard.
+    Cursor,
+}
+
+impl CardFill {
+    /// Both filled tiers carry the selection surface's foregrounds — those are
+    /// the colours picked for a filled row, and a colour chosen for the card
+    /// background is not legible on one.
+    fn filled(self) -> bool {
+        self != CardFill::None
+    }
+}
+
+/// Cards take the cursor's fill only while the sidebar owns focus. An
 /// unfocused highlight remains an edge-marked cursor without claiming the
 /// keyboard via a filled selection background.
-fn card_base(highlighted: bool, focused: bool) -> Style {
+fn card_base(fill: CardFill, focused: bool) -> Style {
     let palette = palette::active();
-    let mut style = palette.surface(highlighted && focused).text_style();
-    if focused && !highlighted {
-        style = style.bg(palette.sidebar_focus_bg);
+    let mut style = palette.surface(fill.filled()).text_style();
+    match fill {
+        CardFill::Cursor => {}
+        CardFill::Pane => style = style.bg(palette.pane_row_bg()),
+        CardFill::None if focused => style = style.bg(palette.sidebar_focus_bg),
+        CardFill::None => {}
     }
     style
 }
@@ -55,6 +80,9 @@ pub struct Sidebar {
     pub sessions: Vec<Session>,
     pub highlight: Option<SidebarItem>,
     pub attached: HashSet<Uuid>,
+    /// The session the active tab's pane is showing. It wears a fill of its
+    /// own, so "in the pane" is not carried by the ● glyph alone.
+    pub pane_session: Option<Uuid>,
 }
 
 #[derive(Debug, Clone, PartialEq, Eq)]
@@ -113,8 +141,7 @@ impl Sidebar {
             lines.push(Line::from(self.group_row(&group, width, focused, home)));
             if !group.collapsed {
                 for s in &group.sessions {
-                    let highlighted = self.highlight == Some(SidebarItem::Session(s.id));
-                    let base = card_base(highlighted, focused);
+                    let base = card_base(self.card_fill(s, focused), focused);
                     lines.push(Line::from(self.name_row(s, width, focused)));
                     let meta = self.meta_row(s, width, focused);
                     lines.push(Line::from(pad_to_width(meta, width, base)));
@@ -226,6 +253,18 @@ impl Sidebar {
         pad_to_width(spans, width, base)
     }
 
+    /// Which fill this session's card wears. The cursor wins on its own row,
+    /// so a highlight parked on the session already in the pane stays visible.
+    fn card_fill(&self, s: &Session, focused: bool) -> CardFill {
+        if focused && self.highlight == Some(SidebarItem::Session(s.id)) {
+            CardFill::Cursor
+        } else if self.pane_session == Some(s.id) {
+            CardFill::Pane
+        } else {
+            CardFill::None
+        }
+    }
+
     fn name_row(&self, s: &Session, width: usize, focused: bool) -> Vec<Span<'static>> {
         let glyph = match (s.status, self.attached.contains(&s.id)) {
             (SessionStatus::Dead, _) => "✗",
@@ -233,12 +272,13 @@ impl Sidebar {
             (SessionStatus::Running, false) => "○",
         };
         let highlighted = self.highlight == Some(SidebarItem::Session(s.id));
-        let base = card_base(highlighted, focused);
+        let fill = self.card_fill(s, focused);
+        let base = card_base(fill, focused);
         let prefix = 1 + INDENT.chars().count() + 2;
         let name_budget = width.saturating_sub(prefix);
 
         let edge = highlighted && !focused;
-        let rail_style = base.fg(activity_color(s.activity, highlighted, focused));
+        let rail_style = base.fg(activity_color(s.activity, fill));
         let mut spans: Vec<Span<'static>> = vec![
             Span::styled(RAIL, rail_style),
             Span::styled(
@@ -257,7 +297,7 @@ impl Sidebar {
         let name_style = if maestro_protocol::display::is_provisional_name(s) {
             base.patch(
                 palette::active()
-                    .surface(highlighted && focused)
+                    .surface(fill.filled())
                     .muted_style()
                     .bg(base.bg.unwrap_or(palette::active().chrome_bg)),
             )
@@ -283,11 +323,11 @@ impl Sidebar {
         let blocked = s.blocked_work.filter(|b| !b.is_clear());
         let dead = s.status == SessionStatus::Dead;
         let highlighted = self.highlight == Some(SidebarItem::Session(s.id));
-        let base = card_base(highlighted, focused);
-        let rail_style =
-            base.patch(Style::default().fg(activity_color(s.activity, highlighted, focused)));
+        let fill = self.card_fill(s, focused);
+        let base = card_base(fill, focused);
+        let rail_style = base.patch(Style::default().fg(activity_color(s.activity, fill)));
         let muted = palette::active()
-            .surface(highlighted && focused)
+            .surface(fill.filled())
             .muted_style()
             .bg(base.bg.unwrap_or(palette::active().chrome_bg));
         let edge = highlighted && !focused;
@@ -308,7 +348,7 @@ impl Sidebar {
         let mut tail: Vec<Span<'static>> = Vec::new();
         if let Some(b) = blocked {
             let palette = palette::active();
-            let surface = palette.surface(highlighted && focused);
+            let surface = palette.surface(fill.filled());
             for (kind, text) in b.stats() {
                 let style = match kind {
                     StatKind::Added => muted.fg(surface.active),
@@ -352,10 +392,8 @@ impl Sidebar {
 /// state word is never spelled out — this colour carries it. The highlighted
 /// card takes its state colours from the selection surface: a colour picked
 /// for the dark card background is not legible on the selection background.
-fn activity_color(state: ActivityState, highlighted: bool, focused: bool) -> Color {
-    palette::active()
-        .surface(highlighted && focused)
-        .activity(state)
+fn activity_color(state: ActivityState, fill: CardFill) -> Color {
+    palette::active().surface(fill.filled()).activity(state)
 }
 
 /// docs/SIDEBAR.md duration format — floored whole seconds / minutes / hours,
@@ -446,6 +484,7 @@ mod tests {
         let mut metadata = HashMap::new();
         metadata.insert("name".into(), serde_json::Value::String(name.into()));
         Session {
+            view: Default::default(),
             id: Uuid::from_u128(id),
             command: "bash".into(),
             cwd: std::path::PathBuf::from("/tmp"),
@@ -461,6 +500,8 @@ mod tests {
             activity_since: Utc::now(),
             current_cwd: None,
             blocked_work: None,
+            last_focused_at: None,
+            acp_session_id: None,
         }
     }
 
@@ -520,6 +561,7 @@ mod tests {
             sessions: vec![session_named(1, "claude"), session_named(2, "bash")],
             highlight: None,
             attached: Default::default(),
+            pane_session: None,
         };
         let rendered = render_to_string(&draw(&sb, 28, 12));
         assert!(
@@ -544,6 +586,7 @@ mod tests {
             sessions: vec![s],
             highlight: None,
             attached: Default::default(),
+            pane_session: None,
         })
         .groups(&HashSet::new());
         assert_eq!(groups[0].key, PathBuf::from("/home/u/repos/maestro"));
@@ -555,6 +598,7 @@ mod tests {
             sessions: Vec::new(),
             highlight: None,
             attached: Default::default(),
+            pane_session: None,
         };
         assert!(sidebar.groups(&HashSet::new()).is_empty());
         assert!(sidebar.rendered_items().is_empty());
@@ -566,6 +610,7 @@ mod tests {
             sessions: vec![session_named(1, "claude"), session_named(2, "bash")],
             highlight: None,
             attached: Default::default(),
+            pane_session: None,
         };
         let key = PathBuf::from("/tmp");
         let mut collapsed = HashSet::new();
@@ -590,6 +635,7 @@ mod tests {
             sessions: vec![session],
             highlight: None,
             attached: Default::default(),
+            pane_session: None,
         };
         let key = PathBuf::from("/very/long/project/path/extraordinarily-long-project-name");
         let collapsed = HashSet::from([key]);
@@ -620,6 +666,7 @@ mod tests {
             sessions: vec![session_named(1, "claude")],
             highlight: None,
             attached: Default::default(),
+            pane_session: None,
         };
         let all = rows(&draw(&sidebar, 40, 8));
         assert!(all[1].contains("/tmp"));
@@ -635,6 +682,7 @@ mod tests {
             sessions: vec![session_named(1, "claude")],
             highlight: None,
             attached: [sid].into_iter().collect(),
+            pane_session: None,
         };
         let all = rows(&draw(&sb, 28, 6));
         let line = row_containing(&all, "claude");
@@ -645,6 +693,87 @@ mod tests {
         );
     }
 
+    /// Whether any cell in the buffer is painted on `bg`.
+    fn any_cell_on(buf: &Buffer, bg: Color) -> bool {
+        (0..buf.area.height)
+            .any(|y| (0..buf.area.width).any(|x| buf[(x, y)].style().bg == Some(bg)))
+    }
+
+    /// docs/SIDEBAR.md: the session the pane is showing wears a fill, so it is
+    /// not the ● glyph alone carrying "this is the one on screen".
+    #[test]
+    fn the_session_in_the_pane_wears_the_pane_fill() {
+        let sid = Uuid::from_u128(1);
+        let p = palette::active();
+        let sb = Sidebar {
+            sessions: vec![session_named(1, "claude")],
+            highlight: None,
+            attached: [sid].into_iter().collect(),
+            pane_session: Some(sid),
+        };
+        assert!(any_cell_on(&draw(&sb, 28, 6), p.pane_row_bg()));
+
+        let none = Sidebar {
+            pane_session: None,
+            ..sb
+        };
+        assert!(!any_cell_on(&draw(&none, 28, 6), p.pane_row_bg()));
+    }
+
+    /// The cursor's fill wins on its own row: a highlight that lands on the
+    /// session already in the pane has to stay visible.
+    #[test]
+    fn the_cursor_outranks_the_pane_fill_on_its_own_row() {
+        let sid = Uuid::from_u128(1);
+        let p = palette::active();
+        let sb = Sidebar {
+            sessions: vec![session_named(1, "claude")],
+            highlight: Some(SidebarItem::Session(sid)),
+            attached: [sid].into_iter().collect(),
+            pane_session: Some(sid),
+        };
+        let buf = draw_with_focus(&sb, 28, 6, true);
+        assert!(any_cell_on(&buf, p.selection.bg), "cursor fill is missing");
+        assert!(
+            !any_cell_on(&buf, p.pane_row_bg()),
+            "the pane fill is showing through the cursor's own row"
+        );
+    }
+
+    /// A card the pane is showing is a filled row, so it takes the selection
+    /// surface's foregrounds — a colour picked for the card background is not
+    /// legible on a fill.
+    #[test]
+    fn the_pane_row_carries_selection_foregrounds() {
+        let sid = Uuid::from_u128(1);
+        let p = palette::active();
+        let mut sess = session_named(1, "claude");
+        sess.activity = ActivityState::AwaitingInput;
+        let sb = Sidebar {
+            sessions: vec![sess],
+            highlight: None,
+            attached: [sid].into_iter().collect(),
+            pane_session: Some(sid),
+        };
+        let buf = draw(&sb, 28, 6);
+        let on_pane_row = |fg: Color| {
+            (0..buf.area.height).any(|y| {
+                (0..buf.area.width).any(|x| {
+                    let st = buf[(x, y)].style();
+                    st.bg == Some(p.pane_row_bg()) && st.fg == Some(fg)
+                })
+            })
+        };
+        assert!(
+            on_pane_row(p.selection.activity(ActivityState::AwaitingInput)),
+            "the rail must carry the state in the filled surface's colours"
+        );
+        assert!(
+            !on_pane_row(p.card.activity(ActivityState::AwaitingInput)),
+            "a card surface colour is painted onto the pane fill"
+        );
+    }
+
     #[test]
     fn dead_session_uses_cross_glyph() {
         let mut sess = session_named(1, "claude");
@@ -653,6 +782,7 @@ mod tests {
             sessions: vec![sess],
             highlight: None,
             attached: Default::default(),
+            pane_session: None,
         };
         let buf = draw(&sb, 28, 6);
         let all = rows(&buf);
@@ -681,6 +811,7 @@ mod tests {
             sessions: vec![blocked, clear, unprobed],
             highlight: None,
             attached: Default::default(),
+            pane_session: None,
         };
         let all = rows(&draw(&sb, 44, 10));
 
@@ -727,6 +858,7 @@ mod tests {
             sessions: vec![generated, settled],
             highlight: None,
             attached: Default::default(),
+            pane_session: None,
         };
         let buf = draw(&sb, 44, 8);
         let palette = palette::active();
@@ -759,6 +891,7 @@ mod tests {
             sessions: vec![s],
             highlight: None,
             attached: Default::default(),
+            pane_session: None,
         };
         let buf = draw(&sb, 44, 8);
         let palette = palette::active();
@@ -785,6 +918,7 @@ mod tests {
             sessions: vec![s],
             highlight: None,
             attached: Default::default(),
+            pane_session: None,
         };
         let all = rows(&draw(&sb, 28, 8));
         assert_eq!(content(&all[0]), "sessions");
@@ -816,6 +950,7 @@ mod tests {
             sessions: vec![s],
             highlight: None,
             attached: Default::default(),
+            pane_session: None,
         };
         let all = rows(&draw(&sb, 28, 8));
         let idx = all.iter().position(|l| l.contains("claude")).unwrap();
@@ -855,6 +990,7 @@ mod tests {
                 sessions: vec![s],
                 highlight: None,
                 attached: Default::default(),
+                pane_session: None,
             };
             let buf = draw(&sb, 28, 8);
             let found = (0..buf.area.height)
@@ -883,6 +1019,7 @@ mod tests {
                 sessions: vec![s],
                 highlight: Some(SidebarItem::Session(Uuid::from_u128(1))),
                 attached: Default::default(),
+                pane_session: None,
             };
             let buf = draw(&sb, 28, 8);
             let on_selection = |fg: Color| {
@@ -922,6 +1059,7 @@ mod tests {
             sessions: vec![s],
             highlight: None,
             attached: Default::default(),
+            pane_session: None,
         };
         let all = rows(&draw(&sb, 28, 8));
         let idx = all.iter().position(|l| l.contains("claude")).unwrap();
@@ -941,6 +1079,7 @@ mod tests {
             sessions: vec![s],
             highlight: None,
             attached: Default::default(),
+            pane_session: None,
         };
         let all = rows(&draw(&sb, 60, 6));
         let meta = content(&all[3]);
@@ -969,6 +1108,7 @@ mod tests {
             sessions: vec![s],
             highlight: None,
             attached: Default::default(),
+            pane_session: None,
         };
         let all = rows(&draw(&sb, 28, 8));
         let idx = all.iter().position(|l| l.contains("claude")).unwrap();
@@ -998,6 +1138,7 @@ mod tests {
             sessions: vec![s],
             highlight: None,
             attached: Default::default(),
+            pane_session: None,
         };
         let all = rows(&draw(&sb, 40, 8));
         let idx = all.iter().position(|l| l.contains("claude")).unwrap();
@@ -1025,6 +1166,7 @@ mod tests {
             sessions: vec![s],
             highlight: None,
             attached: Default::default(),
+            pane_session: None,
         };
         let all = rows(&draw(&sb, 40, 8));
         let idx = all.iter().position(|l| l.contains("claude")).unwrap();
@@ -1053,6 +1195,7 @@ mod tests {
             sessions: vec![s],
             highlight: None,
             attached: Default::default(),
+            pane_session: None,
         };
         let all = rows(&draw(&sb, 42, 8));
         let idx = all.iter().position(|l| l.contains("claude")).unwrap();
@@ -1086,6 +1229,7 @@ mod tests {
             sessions: vec![legacy],
             highlight: None,
             attached: Default::default(),
+            pane_session: None,
         };
         let rendered = render_to_string(&draw(&sb, 40, 8));
         assert!(
@@ -1108,6 +1252,7 @@ mod tests {
     #[test]
     fn falls_back_to_command_when_name_metadata_is_absent() {
         let s = Session {
+            view: Default::default(),
             id: Uuid::from_u128(1),
             command: "vim".into(),
             cwd: std::path::PathBuf::from("/tmp"),
@@ -1123,11 +1268,14 @@ mod tests {
             activity_since: Utc::now(),
             current_cwd: None,
             blocked_work: None,
+            last_focused_at: None,
+            acp_session_id: None,
         };
         let sb = Sidebar {
             sessions: vec![s],
             highlight: None,
             attached: Default::default(),
+            pane_session: None,
         };
         let rendered = render_to_string(&draw(&sb, 28, 6));
         assert!(
@@ -1143,6 +1291,7 @@ mod tests {
             sessions: vec![s],
             highlight: None,
             attached: Default::default(),
+            pane_session: None,
         };
         let all = rows(&draw(&sb, 40, 6));
         assert!(
@@ -1164,6 +1313,7 @@ mod tests {
             sessions: vec![s],
             highlight: None,
             attached: Default::default(),
+            pane_session: None,
         };
         let all = rows(&draw(&sb, 9, 6));
         assert!(
@@ -1190,6 +1340,7 @@ mod tests {
             sessions: vec![s],
             highlight: None,
             attached: Default::default(),
+            pane_session: None,
         };
         let all = rows(&draw(&sb, 29, 6));
         assert!(all[3].contains("~1"), "{:?}", all[3]);
@@ -1214,6 +1365,7 @@ mod tests {
             sessions: vec![s],
             highlight: None,
             attached: Default::default(),
+            pane_session: None,
         };
         let all = rows(&draw(&sb, 40, 6));
         assert!(all[3].contains("~1"), "{:?}", all[3]);
@@ -1235,6 +1387,7 @@ mod tests {
             sessions: vec![highlighted],
             highlight: Some(SidebarItem::Session(Uuid::from_u128(1))),
             attached: Default::default(),
+            pane_session: None,
         };
         let buf = draw(&sb, 28, 8);
         for y in 0..buf.area.height {
@@ -1260,6 +1413,7 @@ mod tests {
             sessions: vec![one, two],
             highlight: Some(SidebarItem::Session(Uuid::from_u128(1))),
             attached: Default::default(),
+            pane_session: None,
         };
         let buf = draw(&sb, 28, 8);
         let all = rows(&buf);
@@ -1295,6 +1449,7 @@ mod tests {
             sessions: vec![session_named(1, "claude")],
             highlight: Some(SidebarItem::Session(Uuid::from_u128(1))),
             attached: Default::default(),
+            pane_session: None,
         };
         let buf = draw_with_focus(&sb, 28, 8, false);
         let y = (0..buf.area.height)
@@ -1314,6 +1469,7 @@ mod tests {
                 sessions: vec![session_named(1, "claude")],
                 highlight: None,
                 attached: Default::default(),
+                pane_session: None,
             },
             28,
             8,
@@ -1334,6 +1490,7 @@ mod tests {
             sessions: vec![s],
             highlight: None,
             attached: Default::default(),
+            pane_session: None,
         };
         let buf = draw(&sb, 28, 8);
         let y = buf.content.iter().position(|c| c.symbol() == "c").unwrap() as u16 / buf.area.width;
@@ -1352,6 +1509,7 @@ mod tests {
             sessions: vec![session_named(1, "claude")],
             highlight: Some(SidebarItem::Session(Uuid::from_u128(1))),
             attached: Default::default(),
+            pane_session: None,
         };
         let all = rows(&draw(&sb, 28, 8));
         let line = content(row_containing(&all, "claude"));
@@ -1369,6 +1527,7 @@ mod tests {
             sessions: vec![one, two],
             highlight: Some(SidebarItem::Session(Uuid::from_u128(1))),
             attached: Default::default(),
+            pane_session: None,
         };
         let all = rows(&draw(&sb, 28, 8));
         let line = row_containing(&all, "bash");
@@ -1388,6 +1547,7 @@ mod tests {
             sessions: vec![s],
             highlight: Some(SidebarItem::Session(Uuid::from_u128(1))),
             attached: Default::default(),
+            pane_session: None,
         };
         let all = rows(&draw(&sb, 28, 8));
         let line = row_containing(&all, "an-unreasonably");

crates/maestro-tui/src/state.rs

@@ -52,6 +52,10 @@ pub enum OverlayKind {
     /// so this stays comparable.
     Rename(Uuid),
     Help,
+    /// The `ctrl-k` command bar (#153). Its query buffer and result list live
+    /// on `App` as [`crate::command_bar::CommandBar`], for the same reason the
+    /// rename buffer does — so this stays comparable.
+    CommandBar,
     Toast(String),
 }
 
@@ -63,6 +67,11 @@ pub struct AppState {
     pub mode: Mode,
     pub sidebar_visible: bool,
     pub sidebar_highlight: Option<SidebarItem>,
+    /// The session the pane is *previewing* (`docs/PREVIEW.md`): shown because
+    /// the sidebar highlight is on it, not because a tab holds it. It never
+    /// enters `tabs`, is never reported to the daemon as focused, and is
+    /// dropped the moment the highlight moves on.
+    pub preview: Option<Uuid>,
     /// Group paths whose cards are hidden. This is UI state rather than
     /// catalog state, so it survives every catalog redraw.
     pub collapsed_sidebar_groups: HashSet<PathBuf>,
@@ -91,6 +100,7 @@ impl AppState {
             mode: Mode::Normal,
             sidebar_visible: true,
             sidebar_highlight: None,
+            preview: None,
             collapsed_sidebar_groups: HashSet::new(),
             overlay: None,
         }
@@ -126,6 +136,9 @@ impl AppState {
     /// drop straight into Insert mode so keystrokes go to the session
     /// without an extra `i` press. The leader returns to Normal.
     pub fn attach_to_focused(&mut self, session_id: Uuid) {
+        // Committing to what was previewed: the pane owns it now, so the
+        // preview has nothing left to say.
+        self.preview = None;
         self.active_tab_mut().pane = Some(session_id);
         self.focus = Focus::Pane;
         self.mode = Mode::Insert;
@@ -150,6 +163,13 @@ impl AppState {
         self.active_tab().session()
     }
 
+    /// What the pane actually draws: the preview when one is up, otherwise the
+    /// active tab's session. A preview covers the pane without replacing it,
+    /// so ending one gives back exactly what was there (`docs/PREVIEW.md`).
+    pub fn displayed_session(&self) -> Option<Uuid> {
+        self.preview.or_else(|| self.active_session())
+    }
+
     /// Move the sidebar highlight one step through the rendered item
     /// sequence, in the direction of `delta` (positive = down), landing only
     /// on items `is_stop` accepts. Only the sign of `delta` matters. Wraps.

crates/maestro-tui/src/structured_task.rs

@@ -0,0 +1,735 @@
+//! Live projection state for one structured session.
+
+use std::collections::HashSet;
+use std::sync::atomic::{AtomicU64, AtomicU8, Ordering};
+use std::sync::{Arc, Mutex};
+use std::time::Duration;
+
+use futures_util::StreamExt;
+use maestro_protocol::{
+    ReducedState, StructuredApprovalDecision, StructuredEvent, TranscriptDelta, TranscriptRow,
+    TranscriptRowKind,
+};
+use tokio::sync::watch;
+use tokio_tungstenite::tungstenite::{Error as WsError, Message};
+
+use crate::input::InputKey;
+use crate::session_task::SessionState;
+use crate::text_input::TextInput;
+
+/// Renderer and input state built directly from the daemon's two projections.
+#[derive(Debug, Clone)]
+pub struct StructuredState {
+    pub rows: Vec<TranscriptRow>,
+    pub reduced: ReducedState,
+    pub selected: Option<String>,
+    pub expanded: HashSet<String>,
+    pub scroll: usize,
+    pub follow_selection: bool,
+    pub composer: TextInput,
+    pub error: Option<String>,
+    submitting: bool,
+    submission_generation: u64,
+    reconcile_submission_on_snapshot: Option<u64>,
+    approval_submitting: bool,
+}
+
+impl Default for StructuredState {
+    fn default() -> Self {
+        Self {
+            rows: Vec::new(),
+            reduced: ReducedState::default(),
+            selected: None,
+            expanded: HashSet::new(),
+            scroll: 0,
+            follow_selection: true,
+            composer: TextInput::default(),
+            error: None,
+            submitting: false,
+            submission_generation: 0,
+            reconcile_submission_on_snapshot: None,
+            approval_submitting: false,
+        }
+    }
+}
+
+impl StructuredState {
+    pub fn apply(&mut self, event: StructuredEvent) {
+        match event {
+            StructuredEvent::TranscriptSnapshot { snapshot } => {
+                let selected = self.selected.clone();
+                self.rows = snapshot.rows;
+                self.selected = selected
+                    .filter(|id| self.rows.iter().any(|row| &row.id == id))
+                    .or_else(|| {
+                        self.rows
+                            .iter()
+                            .rev()
+                            .find(|row| row.kind != TranscriptRowKind::Plan)
+                            .map(|row| row.id.clone())
+                    });
+                self.expanded
+                    .retain(|id| self.rows.iter().any(|row| &row.id == id));
+            }
+            StructuredEvent::ReducedState { state } => {
+                let reconcile_submission = self
+                    .reconcile_submission_on_snapshot
+                    .take()
+                    .is_some_and(|generation| {
+                        self.submitting && generation == self.submission_generation
+                    });
+                self.apply_reduced(state, reconcile_submission);
+            }
+            StructuredEvent::ProjectionUpdate { transcript, state } => {
+                if let Some(delta) = transcript {
+                    self.apply_delta(delta);
+                }
+                self.apply_reduced(state, false);
+            }
+        }
+    }
+
+    fn apply_delta(&mut self, delta: TranscriptDelta) {
+        match delta {
+            TranscriptDelta::Append { row } => {
+                let followed_tail = self.follow_selection
+                    && self.selected.as_ref().is_some_and(|id| {
+                        self.rows
+                            .iter()
+                            .rev()
+                            .find(|old| old.kind != TranscriptRowKind::Plan)
+                            .is_some_and(|old| &old.id == id)
+                    });
+                if let Some(index) = self.rows.iter().position(|old| old.id == row.id) {
+                    self.rows[index] = row.clone();
+                } else {
+                    self.rows.push(row.clone());
+                }
+                if row.kind != TranscriptRowKind::Plan && (self.selected.is_none() || followed_tail)
+                {
+                    self.selected = Some(row.id);
+                }
+            }
+            TranscriptDelta::Patch { row } => {
+                if let Some(index) = self.rows.iter().position(|old| old.id == row.id) {
+                    self.rows[index] = row.clone();
+                } else {
+                    self.rows.push(row.clone());
+                }
+            }
+            TranscriptDelta::Remove { id } => {
+                let removed = self.rows.iter().position(|row| row.id == id);
+                self.rows.retain(|row| row.id != id);
+                self.expanded.remove(&id);
+                if self.selected.as_deref() == Some(&id) {
+                    self.selected = removed.and_then(|index| {
+                        let split = index.min(self.rows.len());
+                        self.rows[split..]
+                            .iter()
+                            .find(|row| row.kind != TranscriptRowKind::Plan)
+                            .or_else(|| {
+                                self.rows[..split]
+                                    .iter()
+                                    .rev()
+                                    .find(|row| row.kind != TranscriptRowKind::Plan)
+                            })
+                            .map(|row| row.id.clone())
+                    });
+                }
+            }
+        }
+    }
+
+    fn apply_reduced(&mut self, state: ReducedState, reconcile_submission: bool) {
+        let previous_nonce = self.pending_nonce().map(str::to_owned);
+        if reconcile_submission || state.turn.responding || state.turn.thinking {
+            self.submitting = false;
+        }
+        self.reduced = state;
+        let next_nonce = self.pending_nonce().map(str::to_owned);
+        if next_nonce != previous_nonce {
+            self.approval_submitting = false;
+            if next_nonce.is_some() {
+                self.selected = self
+                    .rows
+                    .iter()
+                    .rev()
+                    .find(|row| row.kind == TranscriptRowKind::Approval)
+                    .map(|row| row.id.clone());
+                self.follow_selection = true;
+            }
+        }
+    }
+
+    fn prepare_snapshot_reconciliation(&mut self) {
+        self.reconcile_submission_on_snapshot =
+            self.submitting.then_some(self.submission_generation);
+    }
+
+    pub fn select(&mut self, delta: isize) {
+        let selectable: Vec<&TranscriptRow> = self
+            .rows
+            .iter()
+            .filter(|row| row.kind != TranscriptRowKind::Plan)
+            .collect();
+        if selectable.is_empty() {
+            self.selected = None;
+            return;
+        }
+        let current = self
+            .selected
+            .as_ref()
+            .and_then(|id| selectable.iter().position(|row| &row.id == id))
+            .unwrap_or(selectable.len() - 1);
+        let next = if delta >= 0 {
+            current
+                .saturating_add(delta as usize)
+                .min(selectable.len() - 1)
+        } else {
+            current.saturating_sub(delta.unsigned_abs())
+        };
+        self.selected = Some(selectable[next].id.clone());
+        self.follow_selection = true;
+    }
+
+    pub fn toggle_selected(&mut self) {
+        let Some(id) = self.selected.clone() else {
+            return;
+        };
+        let expandable = self.rows.iter().any(|row| {
+            row.id == id
+                && matches!(
+                    row.kind,
+                    TranscriptRowKind::ToolCall | TranscriptRowKind::ToolDiff
+                )
+        });
+        if !expandable {
+            return;
+        }
+        if !self.expanded.insert(id.clone()) {
+            self.expanded.remove(&id);
+        }
+        self.follow_selection = true;
+    }
+
+    pub fn scroll_by(&mut self, lines: isize) {
+        self.scroll = if lines >= 0 {
+            self.scroll.saturating_sub(lines as usize)
+        } else {
+            self.scroll.saturating_add(lines.unsigned_abs())
+        };
+        self.follow_selection = false;
+    }
+
+    pub fn edit_composer(&mut self, key: &InputKey) {
+        if !self.turn_active() {
+            self.composer.handle_key(key);
+            self.error = None;
+        }
+    }
+
+    pub fn begin_prompt(&mut self) -> Option<String> {
+        if self.turn_active() || self.composer.value().trim().is_empty() {
+            return None;
+        }
+        let prompt = self.composer.value().to_string();
+        self.composer = TextInput::default();
+        self.submission_generation = self.submission_generation.wrapping_add(1);
+        self.submitting = true;
+        self.error = None;
+        Some(prompt)
+    }
+
+    pub fn prompt_failed(&mut self, prompt: String, error: String) {
+        if self.composer.value().is_empty() {
+            self.composer = TextInput::with_value(prompt);
+        }
+        self.submitting = false;
+        self.error = Some(error);
+    }
+
+    pub fn turn_active(&self) -> bool {
+        self.submitting || self.reduced.turn.responding || self.reduced.turn.thinking
+    }
+
+    pub fn pending_nonce(&self) -> Option<&str> {
+        self.reduced
+            .pending_approval
+            .as_ref()?
+            .get("nonce")?
+            .as_str()
+    }
+
+    pub fn approval_decision(&mut self, key: char) -> Option<(String, StructuredApprovalDecision)> {
+        if self.approval_submitting {
+            return None;
+        }
+        let selected = self.selected.as_deref()?;
+        let pending_row = self
+            .rows
+            .iter()
+            .rev()
+            .find(|row| row.kind == TranscriptRowKind::Approval)?;
+        if pending_row.id != selected {
+            return None;
+        }
+        let decision = match key {
+            'a' => StructuredApprovalDecision::AllowOnce,
+            'A' => StructuredApprovalDecision::AllowForSession,
+            'd' => StructuredApprovalDecision::Deny,
+            _ => return None,
+        };
+        let offered = offered_decisions(&pending_row.data);
+        if !offered.contains(&decision) {
+            return None;
+        }
+        let nonce = self.pending_nonce()?.to_string();
+        self.approval_submitting = true;
+        self.error = None;
+        Some((nonce, decision))
+    }
+
+    pub fn approval_failed(&mut self, nonce: &str, error: String) {
+        if self.pending_nonce() != Some(nonce) {
+            return;
+        }
+        self.approval_submitting = false;
+        self.error = Some(error);
+    }
+}
+
+pub fn offered_decisions(data: &serde_json::Value) -> Vec<StructuredApprovalDecision> {
+    let mut out = Vec::new();
+    for kind in data
+        .get("options")
+        .and_then(serde_json::Value::as_array)
+        .into_iter()
+        .flatten()
+        .filter_map(|option| option.get("kind").and_then(serde_json::Value::as_str))
+    {
+        match kind {
+            "allow_once" if !out.contains(&StructuredApprovalDecision::AllowOnce) => {
+                out.push(StructuredApprovalDecision::AllowOnce)
+            }
+            "allow_always" if !out.contains(&StructuredApprovalDecision::AllowForSession) => {
+                out.push(StructuredApprovalDecision::AllowForSession)
+            }
+            "reject_once" | "reject_always" if !out.contains(&StructuredApprovalDecision::Deny) => {
+                out.push(StructuredApprovalDecision::Deny)
+            }
+            _ => {}
+        }
+    }
+    out
+}
+
+/// Cheap shared handle for a structured projection connection.
+#[derive(Clone)]
+pub struct StructuredHandle {
+    pub state: Arc<Mutex<StructuredState>>,
+    connection: Arc<AtomicU8>,
+    revision: Arc<AtomicU64>,
+    stop: watch::Sender<bool>,
+}
+
+impl std::fmt::Debug for StructuredHandle {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        f.debug_struct("StructuredHandle")
+            .field("connection", &self.connection())
+            .field("revision", &self.revision())
+            .finish_non_exhaustive()
+    }
+}
+
+impl StructuredHandle {
+    pub fn connection(&self) -> SessionState {
+        match self.connection.load(Ordering::Acquire) {
+            0 => SessionState::Connecting,
+            1 => SessionState::Live,
+            2 => SessionState::Reconnecting,
+            _ => SessionState::Ended,
+        }
+    }
+
+    pub fn revision(&self) -> u64 {
+        self.revision.load(Ordering::Acquire)
+    }
+
+    pub fn end(&self) {
+        self.connection
+            .store(SessionState::Ended as u8, Ordering::Release);
+        let _ = self.stop.send(true);
+    }
+
+    #[cfg(test)]
+    pub(crate) fn test_handle(state: StructuredState) -> Self {
+        let (stop, _) = watch::channel(false);
+        Self {
+            state: Arc::new(Mutex::new(state)),
+            connection: Arc::new(AtomicU8::new(SessionState::Live as u8)),
+            revision: Arc::new(AtomicU64::new(0)),
+            stop,
+        }
+    }
+}
+
+#[derive(Debug)]
+pub struct StructuredTask;
+
+impl StructuredTask {
+    pub fn spawn(ws_url: String) -> StructuredHandle {
+        let state = Arc::new(Mutex::new(StructuredState::default()));
+        let connection = Arc::new(AtomicU8::new(SessionState::Connecting as u8));
+        let revision = Arc::new(AtomicU64::new(0));
+        let (stop, mut stopped) = watch::channel(false);
+        let handle = StructuredHandle {
+            state: state.clone(),
+            connection: connection.clone(),
+            revision: revision.clone(),
+            stop,
+        };
+
+        tokio::spawn(async move {
+            let mut backoff = Duration::from_secs(1);
+            loop {
+                if *stopped.borrow() {
+                    return;
+                }
+                state
+                    .lock()
+                    .expect("structured state mutex")
+                    .prepare_snapshot_reconciliation();
+                connection.store(SessionState::Connecting as u8, Ordering::Release);
+                let connected = tokio::select! {
+                    result = tokio_tungstenite::connect_async(&ws_url) => result,
+                    _ = stopped.changed() => return,
+                };
+                let (mut ws, _) = match connected {
+                    Ok(value) => value,
+                    Err(error) => {
+                        if terminal_handshake_error(&error) {
+                            state.lock().expect("structured state mutex").error =
+                                Some(format!("cannot open structured session: {error}"));
+                            connection.store(SessionState::Ended as u8, Ordering::Release);
+                            revision.fetch_add(1, Ordering::Release);
+                            return;
+                        }
+                        connection.store(SessionState::Reconnecting as u8, Ordering::Release);
+                        revision.fetch_add(1, Ordering::Release);
+                        tokio::select! {
+                            _ = tokio::time::sleep(super::session_task::jitter(backoff)) => {},
+                            _ = stopped.changed() => return,
+                        }
+                        backoff = backoff.saturating_mul(2).min(Duration::from_secs(30));
+                        continue;
+                    }
+                };
+                backoff = Duration::from_secs(1);
+                connection.store(SessionState::Live as u8, Ordering::Release);
+                revision.fetch_add(1, Ordering::Release);
+
+                loop {
+                    let frame = tokio::select! {
+                        frame = ws.next() => frame,
+                        _ = stopped.changed() => return,
+                    };
+                    match frame {
+                        Some(Ok(Message::Text(text))) => {
+                            if let Ok(event) = serde_json::from_str::<StructuredEvent>(&text) {
+                                state.lock().expect("structured state mutex").apply(event);
+                                revision.fetch_add(1, Ordering::Release);
+                            }
+                        }
+                        Some(Ok(Message::Close(_))) | None | Some(Err(_)) => break,
+                        _ => {}
+                    }
+                }
+                connection.store(SessionState::Reconnecting as u8, Ordering::Release);
+                revision.fetch_add(1, Ordering::Release);
+                tokio::select! {
+                    _ = tokio::time::sleep(super::session_task::jitter(backoff)) => {},
+                    _ = stopped.changed() => return,
+                }
+                backoff = backoff.saturating_mul(2).min(Duration::from_secs(30));
+            }
+        });
+        handle
+    }
+}
+
+fn terminal_handshake_error(error: &WsError) -> bool {
+    matches!(error, WsError::Http(response) if response.status().is_client_error())
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+    use maestro_protocol::{TranscriptSnapshot, TurnState};
+    use serde_json::json;
+
+    fn row(id: &str, kind: TranscriptRowKind, data: serde_json::Value) -> TranscriptRow {
+        TranscriptRow {
+            id: id.into(),
+            kind,
+            data,
+        }
+    }
+
+    #[test]
+    fn snapshots_replace_and_deltas_address_rows_by_id() {
+        let mut state = StructuredState::default();
+        state.apply(StructuredEvent::TranscriptSnapshot {
+            snapshot: TranscriptSnapshot {
+                cursor: 2,
+                rows: vec![row("a", TranscriptRowKind::AgentText, json!({}))],
+            },
+        });
+        state.apply(StructuredEvent::ProjectionUpdate {
+            transcript: Some(TranscriptDelta::Patch {
+                row: row("a", TranscriptRowKind::AgentText, json!({"n": 2})),
+            }),
+            state: ReducedState::default(),
+        });
+        state.apply(StructuredEvent::ProjectionUpdate {
+            transcript: Some(TranscriptDelta::Append {
+                row: row("b", TranscriptRowKind::Notice, json!({})),
+            }),
+            state: ReducedState::default(),
+        });
+        assert_eq!(state.rows.len(), 2);
+        assert_eq!(state.rows[0].data["n"], 2);
+
+        state.apply(StructuredEvent::TranscriptSnapshot {
+            snapshot: TranscriptSnapshot {
+                cursor: 5,
+                rows: vec![row("b", TranscriptRowKind::Notice, json!({"fresh": true}))],
+            },
+        });
+        assert_eq!(state.rows.len(), 1);
+        assert_eq!(state.rows[0].data["fresh"], true);
+    }
+
+    #[test]
+    fn selection_survives_patch_and_moves_after_remove() {
+        let mut state = StructuredState {
+            rows: vec![
+                row("a", TranscriptRowKind::Notice, json!({})),
+                row("b", TranscriptRowKind::ToolCall, json!({})),
+                row("plan", TranscriptRowKind::Plan, json!({})),
+            ],
+            selected: Some("a".into()),
+            ..StructuredState::default()
+        };
+        state.select(1);
+        assert_eq!(state.selected.as_deref(), Some("b"));
+        state.toggle_selected();
+        assert!(state.expanded.contains("b"));
+        state.apply_delta(TranscriptDelta::Remove { id: "b".into() });
+        assert_eq!(state.selected.as_deref(), Some("a"));
+
+        state.apply_delta(TranscriptDelta::Remove { id: "a".into() });
+        assert_eq!(
+            state.selected, None,
+            "collapsed plan rows are not selectable"
+        );
+    }
+
+    #[test]
+    fn approval_keys_only_offer_server_backed_decisions() {
+        let mut state = StructuredState::default();
+        state.rows.push(row(
+            "approval:1",
+            TranscriptRowKind::Approval,
+            json!({"options":[
+                {"kind":"allow_once"}, {"kind":"reject_always"}
+            ]}),
+        ));
+        state.selected = Some("approval:1".into());
+        state.reduced.pending_approval = Some(json!({"nonce":"secret"}));
+        assert_eq!(
+            state.approval_decision('A'),
+            None,
+            "allow-for-session was not offered"
+        );
+        assert_eq!(
+            state.approval_decision('a'),
+            Some(("secret".into(), StructuredApprovalDecision::AllowOnce))
+        );
+    }
+
+    #[test]
+    fn resolved_approval_ignores_its_late_failure() {
+        let mut state = StructuredState::default();
+        state.rows.push(row(
+            "approval:1",
+            TranscriptRowKind::Approval,
+            json!({"options":[{"kind":"allow_once"}]}),
+        ));
+        state.selected = Some("approval:1".into());
+        state.reduced.pending_approval = Some(json!({"nonce":"old"}));
+        assert!(state.approval_decision('a').is_some());
+
+        state.apply(StructuredEvent::ProjectionUpdate {
+            transcript: None,
+            state: ReducedState::default(),
+        });
+        state.approval_failed("old", "response lost".into());
+
+        assert_eq!(state.error, None);
+        assert!(!state.approval_submitting);
+    }
+
+    #[test]
+    fn superseded_approval_ignores_its_late_failure() {
+        let mut state = StructuredState::default();
+        state.rows.push(row(
+            "approval:1",
+            TranscriptRowKind::Approval,
+            json!({"options":[{"kind":"allow_once"}]}),
+        ));
+        state.selected = Some("approval:1".into());
+        state.reduced.pending_approval = Some(json!({"nonce":"old"}));
+        assert!(state.approval_decision('a').is_some());
+
+        state.rows.push(row(
+            "approval:2",
+            TranscriptRowKind::Approval,
+            json!({"options":[{"kind":"allow_once"}]}),
+        ));
+        state.apply(StructuredEvent::ProjectionUpdate {
+            transcript: None,
+            state: ReducedState {
+                pending_approval: Some(json!({"nonce":"new"})),
+                ..ReducedState::default()
+            },
+        });
+        assert_eq!(
+            state.approval_decision('a'),
+            Some(("new".into(), StructuredApprovalDecision::AllowOnce))
+        );
+
+        state.approval_failed("old", "response lost".into());
+
+        assert_eq!(state.error, None);
+        assert!(state.approval_submitting);
+    }
+
+    #[test]
+    fn matching_approval_surfaces_its_failure() {
+        let mut state = StructuredState::default();
+        state.rows.push(row(
+            "approval:1",
+            TranscriptRowKind::Approval,
+            json!({"options":[{"kind":"allow_once"}]}),
+        ));
+        state.selected = Some("approval:1".into());
+        state.reduced.pending_approval = Some(json!({"nonce":"current"}));
+        assert!(state.approval_decision('a').is_some());
+
+        state.approval_failed("current", "request failed".into());
+
+        assert_eq!(state.error.as_deref(), Some("request failed"));
+        assert!(!state.approval_submitting);
+    }
+
+    #[test]
+    fn composer_is_gated_by_the_projected_turn_lifecycle() {
+        let mut state = StructuredState::default();
+        state.edit_composer(&InputKey::char('h'));
+        state.edit_composer(&InputKey::char('i'));
+        assert_eq!(state.begin_prompt().as_deref(), Some("hi"));
+        assert!(state.turn_active());
+        state.prompt_failed("hi".into(), "nope".into());
+        assert_eq!(state.composer.value(), "hi");
+
+        state.reduced.turn = TurnState {
+            responding: true,
+            ..TurnState::default()
+        };
+        state.edit_composer(&InputKey::char('x'));
+        assert_eq!(state.composer.value(), "hi");
+    }
+
+    #[test]
+    fn authoritative_idle_snapshot_reconciles_a_wholly_missed_turn() {
+        let mut state = StructuredState::default();
+        state.edit_composer(&InputKey::char('h'));
+        state.edit_composer(&InputKey::char('i'));
+        assert_eq!(state.begin_prompt().as_deref(), Some("hi"));
+
+        state.apply(StructuredEvent::ProjectionUpdate {
+            transcript: None,
+            state: ReducedState::default(),
+        });
+        assert!(
+            state.turn_active(),
+            "an ordinary idle update must not reopen the composer before turn begin"
+        );
+
+        state.prepare_snapshot_reconciliation();
+        state.apply(StructuredEvent::TranscriptSnapshot {
+            snapshot: TranscriptSnapshot {
+                cursor: 0,
+                rows: Vec::new(),
+            },
+        });
+        state.apply(StructuredEvent::ReducedState {
+            state: ReducedState::default(),
+        });
+        assert!(
+            !state.turn_active(),
+            "a reconnect snapshot must settle a submission whose whole turn was missed"
+        );
+    }
+
+    #[test]
+    fn stale_handshake_state_does_not_settle_a_new_submission() {
+        let mut state = StructuredState::default();
+        state.prepare_snapshot_reconciliation();
+        state.apply(StructuredEvent::TranscriptSnapshot {
+            snapshot: TranscriptSnapshot {
+                cursor: 0,
+                rows: Vec::new(),
+            },
+        });
+
+        state.edit_composer(&InputKey::char('h'));
+        state.edit_composer(&InputKey::char('i'));
+        assert_eq!(state.begin_prompt().as_deref(), Some("hi"));
+        state.apply(StructuredEvent::ReducedState {
+            state: ReducedState::default(),
+        });
+
+        assert!(
+            state.turn_active(),
+            "state captured before this submission must not reopen the composer"
+        );
+    }
+
+    #[test]
+    fn failed_submission_reconciliation_does_not_settle_its_successor() {
+        let mut state = StructuredState::default();
+        state.edit_composer(&InputKey::char('a'));
+        assert_eq!(state.begin_prompt().as_deref(), Some("a"));
+        state.prepare_snapshot_reconciliation();
+
+        state.prompt_failed("a".into(), "nope".into());
+        state.composer = TextInput::with_value("b");
+        assert_eq!(state.begin_prompt().as_deref(), Some("b"));
+
+        state.apply(StructuredEvent::TranscriptSnapshot {
+            snapshot: TranscriptSnapshot {
+                cursor: 0,
+                rows: Vec::new(),
+            },
+        });
+        state.apply(StructuredEvent::ReducedState {
+            state: ReducedState::default(),
+        });
+
+        assert!(
+            state.turn_active(),
+            "a reconnect for the failed submission must not settle its successor"
+        );
+    }
+}

crates/maestro-tui/tests/structured_http.rs

@@ -0,0 +1,79 @@
+//! The TUI's structured actions use the shared typed daemon client; assert the
+//! exact route and bare approval decision body at the HTTP boundary.
+
+use std::sync::{Arc, Mutex};
+
+use axum::extract::{Path, State};
+use axum::routing::post;
+use axum::{Json, Router};
+use maestro_protocol::{DaemonClient, StructuredApprovalDecision, StructuredPromptRequest};
+use uuid::Uuid;
+
+#[derive(Debug, Default)]
+struct Seen {
+    prompt: Option<String>,
+    cancelled: bool,
+    approval: Option<(String, StructuredApprovalDecision)>,
+}
+
+type Shared = Arc<Mutex<Seen>>;
+
+async fn prompt(
+    State(seen): State<Shared>,
+    Path(_id): Path<Uuid>,
+    Json(body): Json<StructuredPromptRequest>,
+) {
+    seen.lock().unwrap().prompt = Some(body.prompt);
+}
+
+async fn cancel(State(seen): State<Shared>, Path(_id): Path<Uuid>) {
+    seen.lock().unwrap().cancelled = true;
+}
+
+async fn approval(
+    State(seen): State<Shared>,
+    Path((_id, nonce)): Path<(Uuid, String)>,
+    Json(decision): Json<StructuredApprovalDecision>,
+) {
+    seen.lock().unwrap().approval = Some((nonce, decision));
+}
+
+#[tokio::test(flavor = "multi_thread")]
+async fn prompt_cancel_and_approval_use_structured_api_contract() {
+    let seen = Shared::default();
+    let app = Router::new()
+        .route("/api/sessions/:id/structured/prompt", post(prompt))
+        .route("/api/sessions/:id/structured/cancel", post(cancel))
+        .route(
+            "/api/sessions/:id/structured/approvals/:nonce",
+            post(approval),
+        )
+        .with_state(seen.clone());
+    let listener = tokio::net::TcpListener::bind("127.0.0.1:0").await.unwrap();
+    let addr = listener.local_addr().unwrap();
+    tokio::spawn(async move { axum::serve(listener, app).await.unwrap() });
+
+    let client = DaemonClient::new(format!("http://{addr}"));
+    let id = Uuid::from_u128(141);
+    client.send_structured_prompt(id, "ship it").await.unwrap();
+    client.cancel_structured_turn(id).await.unwrap();
+    client
+        .resolve_structured_approval(
+            id,
+            "one-use-nonce",
+            StructuredApprovalDecision::AllowForSession,
+        )
+        .await
+        .unwrap();
+
+    let seen = seen.lock().unwrap();
+    assert_eq!(seen.prompt.as_deref(), Some("ship it"));
+    assert!(seen.cancelled);
+    assert_eq!(
+        seen.approval,
+        Some((
+            "one-use-nonce".into(),
+            StructuredApprovalDecision::AllowForSession
+        ))
+    );
+}

crates/maestro-tui/tests/structured_task_ws.rs

@@ -0,0 +1,107 @@
+//! Projection socket coverage: snapshots replace state on reconnect and live
+//! deltas patch rows without client-side event folding.
+
+use std::sync::atomic::{AtomicUsize, Ordering};
+use std::sync::Arc;
+use std::time::Duration;
+
+use axum::extract::ws::{Message, WebSocketUpgrade};
+use axum::extract::State;
+use axum::response::Response;
+use axum::routing::any;
+use axum::Router;
+use maestro_protocol::{
+    ReducedState, StructuredEvent, TranscriptDelta, TranscriptRow, TranscriptRowKind,
+    TranscriptSnapshot,
+};
+use maestro_tui::session_task::SessionState;
+use maestro_tui::structured_task::StructuredTask;
+use serde_json::json;
+
+async fn structured_handler(
+    State(connects): State<Arc<AtomicUsize>>,
+    ws: WebSocketUpgrade,
+) -> Response {
+    ws.on_upgrade(move |mut socket| async move {
+        let attempt = connects.fetch_add(1, Ordering::SeqCst);
+        let snapshot = if attempt == 0 {
+            TranscriptSnapshot {
+                cursor: 1,
+                rows: vec![row("old", json!({"content":{"type":"text","text":"old"}}))],
+            }
+        } else {
+            TranscriptSnapshot {
+                cursor: 3,
+                rows: vec![row("live", json!({"content":{"type":"text","text":"one"}}))],
+            }
+        };
+        send(
+            &mut socket,
+            StructuredEvent::TranscriptSnapshot { snapshot },
+        )
+        .await;
+        if attempt == 0 {
+            let _ = socket.close().await;
+            return;
+        }
+        send(
+            &mut socket,
+            StructuredEvent::ProjectionUpdate {
+                transcript: Some(TranscriptDelta::Patch {
+                    row: row("live", json!({"content":{"type":"text","text":"two"}})),
+                }),
+                state: ReducedState {
+                    model: Some("test-model".into()),
+                    ..ReducedState::default()
+                },
+            },
+        )
+        .await;
+        tokio::time::sleep(Duration::from_secs(3)).await;
+    })
+}
+
+fn row(id: &str, data: serde_json::Value) -> TranscriptRow {
+    TranscriptRow {
+        id: id.into(),
+        kind: TranscriptRowKind::AgentText,
+        data,
+    }
+}
+
+async fn send(socket: &mut axum::extract::ws::WebSocket, event: StructuredEvent) {
+    socket
+        .send(Message::Text(serde_json::to_string(&event).unwrap()))
+        .await
+        .unwrap();
+}
+
+#[tokio::test(flavor = "multi_thread")]
+async fn reconnect_snapshot_replaces_then_delta_patches_projection() {
+    let connects = Arc::new(AtomicUsize::new(0));
+    let app = Router::new()
+        .route("/api/structured/x", any(structured_handler))
+        .with_state(connects.clone());
+    let listener = tokio::net::TcpListener::bind("127.0.0.1:0").await.unwrap();
+    let addr = listener.local_addr().unwrap();
+    tokio::spawn(async move { axum::serve(listener, app).await.unwrap() });
+
+    let handle = StructuredTask::spawn(format!("ws://{addr}/api/structured/x"));
+    for _ in 0..250 {
+        tokio::time::sleep(Duration::from_millis(10)).await;
+        let state = handle.state.lock().unwrap().clone();
+        if state.reduced.model.as_deref() == Some("test-model") {
+            assert_eq!(state.rows.len(), 1);
+            assert_eq!(state.rows[0].id, "live");
+            assert_eq!(state.rows[0].data["content"]["text"], "two");
+            assert!(connects.load(Ordering::SeqCst) >= 2);
+            handle.end();
+            assert_eq!(handle.connection(), SessionState::Ended);
+            return;
+        }
+    }
+    panic!(
+        "structured projection never reached reconnect delta; connection={:?}",
+        handle.connection()
+    );
+}

docs/COMMAND-BAR.md

@@ -0,0 +1,492 @@
+# COMMAND-BAR.md — the command bar contract
+
+One rule for the `ctrl-k` command bar in both clients, so the web bar and the
+TUI bar open the same way, rank the same results in the same order, and act on
+the same keys. Read this before changing either. Both clients implement exactly
+what is written here; if the behaviour needs to change, change it here first.
+
+The bar is one surface with three jobs: **go to a session**, **run a command**,
+**spawn into a directory**. It is not a new place to configure anything and it
+does not own any action — it chooses one and hands off to the flow that already
+implements it.
+
+## Opening
+
+`ctrl-k` opens the bar from anywhere:
+
+| Client | From | Notes |
+| --- | --- | --- |
+| TUI | Normal mode | Sidebar has the keyboard. |
+| TUI | Insert mode | The pane has the keyboard; the bar still opens. |
+| Web | Sidebar focused | Ordinary global binding. |
+| Web | Terminal focused | Intercepted before xterm sees it. |
+
+It is a **keymap entry like any other**, not a hard-wired key. In the TUI it is
+bound in both `DEFAULT_NORMAL` and `DEFAULT_INSERT` and is rebindable through
+`[tui.keymap.*]`; because the help overlay builds its lines from the live
+keymap, it appears there without a second list to maintain. In the web it is an
+entry in the command registry, so the `?` overlay lists it for the same reason.
+
+An attached xterm swallows every keystroke it is given, so the web binding is
+handled in the **capture phase**, ahead of the terminal — the same way the
+restart overlay swallows the app's shortcuts (`docs/RESTART.md`).
+
+### Escape hatch — sending a literal Ctrl-K
+
+Binding `ctrl-k` takes readline's kill-to-end-of-line away from every pane. The
+leader gives it back: **leader then `ctrl-k`** — `ctrl-a ctrl-k` by default —
+sends the literal `0x0B` byte to the focused pane and does not open the bar.
+
+The TUI already has a leader (`ctrl-a`, `[tui].leader`), and this chord goes
+through the existing chord resolution, so rebinding the leader rebinds the
+escape hatch with it — exactly as the leader's Insert-mode escape already
+works. **The web gains a leader for this**, defaulting to `ctrl-a` and
+mirroring the TUI's. `ctrl-a` is select-all in a browser; the web
+`preventDefault`s it, since selecting all of a terminal pane does nothing
+useful.
+
+One knob drives both clients: the daemon serves `[tui].leader` as `leader` on
+`GET /api/info`, and the web binds that instead of its own constant (#159). A
+daemon too old to send the field, or an unreachable `/api/info`, leaves the web
+on `ctrl-a`. The section is named `[tui]` for history — it is the leader for
+every client, not the TUI's alone.
+
+The leader itself needs the same kind of way back: holding it consumes every
+press, on both clients, even before anything is bound behind it. Pressing it
+twice — `ctrl-a ctrl-a` by default — sends one literal leader byte to the
+focused pane and clears the pending chord, the way tmux resolves a doubled
+prefix key. This chord is also built from the configured leader, so a
+rebound leader carries its own escape hatch with it.
+
+Only Ctrl-K and the leader itself get an escape hatch. No other control
+character is intercepted, so none of them needs one.
+
+### Focus round-trip
+
+Closing the bar returns the keyboard to whatever held it when the bar opened,
+the terminal included. A round trip through the bar never silently moves focus,
+and never counts as a focus change for the daemon: opening the bar does not
+report the pane unfocused, and closing it does not report a new focus. The bar
+is a view over the app, not a place in it.
+
+Opening the bar while a session is previewed (`docs/PREVIEW.md`) discards the
+preview first, like any other real change; the bar is not previewed into.
+
+## Structure
+
+The bar is a query line over a result list. By default the list is **flat and
+mixed** — sessions and commands ranked together — and rendered under **kind
+headers**: a header row naming the kind, then that kind's results.
+
+Grouping is a rendering of the ranking, never a reordering of it:
+
+- Results are ranked as one list by the algorithm below.
+- A kind's group holds its matches in that rank order.
+- **Groups are ordered by their best-scoring member.** The first row under the
+  first header is therefore the globally best result, and the highlight starts
+  on it.
+
+Two sigils, typed as the **first character** of the query, narrow the list to
+one kind:
+
+| Sigil | Kind | Candidates | Enter |
+| --- | --- | --- | --- |
+| `>` | commands | Every entry in the client's command registry — the web registry from the `?` overlay, the TUI's live `(chord, Action)` keymap for the current mode. | Runs the command. |
+| `~` | directories | Recent dirs (`GET /api/recent-dirs`) and the project list the spawn form already uses, with `GET /api/dirs` filling in as a path is typed. | Spawns a session there with every default resolved. |
+
+While a sigil is in force there is one kind, so the kind header is dropped. A
+command row shows its **key chord** beside its label, so the bar teaches the
+keymap instead of replacing it. A `~` spawn takes the same fast-forward path as
+`N` / `FastForwardSpawn`: an unresolvable default opens the pre-filled spawn
+form rather than failing silently.
+
+**Backspacing past a sigil returns to the mixed list.** The sigil is one
+character of the query like any other — deleting it is not a special key, it is
+the query becoming empty again.
+
+The sigil is only a sigil in first position. `>` or `~` typed anywhere else is
+a literal query character (a directory query is where a `~` is most likely to
+be typed twice, and the second one must reach the matcher).
+
+## Empty query
+
+With no sigil and an empty query the bar lists **sessions only, most recently
+focused first**, so `ctrl-k enter` is "back to where I just was". Commands and
+directories need a sigil or a query to appear; an empty bar is a session
+switcher.
+
+**Recency comes from the daemon**, not from client state — the same order in
+every client, on every device, including one that just loaded the page. The
+daemon stamps a last-focused time per session and ships it on the session like
+any other field (#145). Both of the ways focus moves stamp the same field: a
+client opening `/api/attach/:id`, and a client reporting focus explicitly at
+`POST /api/sessions/:id/focus` when it refocuses a pane that is already open.
+
+**A session that has never been focused sorts after every session that has**,
+and among those, most recently created first. Dead sessions sort after live
+ones regardless of recency: a session you cannot attach to is not where you
+just were.
+
+Under `>` an empty query lists every command in registry order. Under `~` it
+lists recent dirs, most recent first, then the project list.
+
+## Keys
+
+| Key | Action |
+| --- | --- |
+| `enter` | Open the highlighted result — attach the session, run the command, spawn into the directory. |
+| `tab` | Drill into the highlighted **session**'s action page. No effect on any other kind. |
+| `esc` | At the top level, close the bar. On an action page, return to the result list. |
+| `backspace` | Ordinary editing; at an empty query on an action page, return to the result list. |
+| `up` / `down` | Move the highlight. |
+| `ctrl-p` / `ctrl-n` | Move the highlight. |
+
+The highlight does not wrap: it stops at the first and last row. Kind headers
+are never landed on — they are labels, not rows.
+
+Enter on a session goes through the **same open path** the sidebar's click and
+the hash router already share, so a bar attach can never leave the layout in a
+state a click could not produce.
+
+### Drill-in — the session action page
+
+`tab` on a highlighted session opens that session's action page inside the same
+overlay: **kill**, **rename**, **spawn similar**. The page is still fuzzy
+searchable — the query line keeps working, now over those actions.
+
+- The overlay names the session being acted on, so the target is never
+  ambiguous.
+- Escape, or backspace at an empty query, returns to the result list **with the
+  previous query intact**. Drilling in and backing out is free.
+- Each action raises the flow it already has: kill through the confirmation
+  both clients ask for (`docs/SIDEBAR.md`) and the blockers dialog behind it
+  (`docs/WORKTREES.md`), rename through the existing prompt pre-filled with the
+  session's own name (`docs/SIDEBAR.md`), spawn similar through the spawn form
+  seeded from the session's directory and command. The bar picks the action; it
+  never reimplements one.
+
+No actions beyond those three, and no action across more than one session.
+
+## Touch entry
+
+On the web, **tapping or focusing the sidebar's search field opens the bar**
+with an empty query. There is no `ctrl-k` on a phone and the product is
+mobile-first, so the field the operator already reaches for is the entry point.
+
+This **replaces** the sidebar's inline substring filter — one search affordance
+in the header, not two beside each other. The tree's "No matches" empty state
+belonged to that filter and goes with it; the bar's own no-results state takes
+over (see the fixture `F4`).
+
+At phone width the bar follows the bottom-sheet treatment the spawn modal
+already uses below 600px. Visuals otherwise come from `DESIGN.md`'s existing
+overlay tokens — the bar is the same family of surface as the spawn modal and
+the help overlay, not a new one.
+
+## What a candidate is
+
+The matcher is a pure function: `(query, candidates) → ranked subset with
+matched ranges`. It knows nothing about sessions, panes or the network. A
+candidate is a **kind** plus a set of **named text fields**, each with a fixed
+weight.
+
+| Kind | Field | Weight | Text |
+| --- | --- | --- | --- |
+| session | `name` | `0` | The name as the sidebar shows it: `metadata.name` if set, else the command line (`docs/SIDEBAR.md`'s fallback). |
+| session | `directory` | `-24` | The directory the sidebar groups it under, abbreviated: `~/dev/api`, not `/home/me/dev/api`. |
+| session | `command` | `-32` | The full command line, arguments included. |
+| session | `tool` | `-40` | The tool id the card's icon stands for (`claude`, `codex`, `opencode`, …), absent when the program is not one we have a mark for. |
+| command | `label` | `0` | The plain-language label — the web registry's label, the TUI's `Action::help_label`. |
+| directory | `path` | `0` | The path as displayed, abbreviated the same way. |
+
+A command's **key chord is displayed, not matched**. It is there to teach the
+keymap; matching it would make `>` results depend on a user's rebinds, and the
+two clients do not share a keymap.
+
+A candidate **matches** if at least one of its fields matches. Its score is the
+**best** `field score + field weight` across its fields, and the matched ranges
+it returns are those of that winning field — so a session found through its
+directory highlights inside the directory, not inside its name.
+
+## Match and rank
+
+Two independent implementations (#146 in TypeScript, #147 in Rust) must produce
+the same order for the same input. Everything below is exact.
+
+### Normalization
+
+- **Query**: lowercase, then remove every whitespace character. The result is
+  the *normalized query*. If it is empty, see "Empty query" below.
+- **Field text**: matched against its lowercased form. Bonuses are computed
+  against the **original** text, because case is a signal (`camelCase`) that
+  lowercasing destroys.
+- **Compact form** of a string: lowercase with whitespace removed. Used only
+  for the exact and prefix tests.
+
+Lowercasing is per-character simple lowercase (`char::to_lowercase` /
+`String.prototype.toLowerCase`). Positions are **character** positions —
+Unicode scalar values in Rust, UTF-16 code units in TypeScript, which agree for
+every character these fields realistically hold; ranges are returned in the
+host language's own unit, since they exist to slice that language's string.
+
+### What a match is
+
+Case-insensitive **subsequence**: every character of the normalized query
+appears in the lowercased field text, in order, not necessarily adjacent. A
+field with no such embedding does not match.
+
+### Word boundaries
+
+A matched character at position `p` earns exactly one character bonus, taking
+the first rule that applies:
+
+| Rule | Bonus |
+| --- | --- |
+| `p == 0` — first character of the field | `+18` |
+| The character before it is a **separator**: `/` `\` `-` `_` `.` `:` or a space | `+16` |
+| It is uppercase and the character before it is lowercase (a camelCase hump) | `+12` |
+| It is a digit and the character before it is not | `+12` |
+| Otherwise | `0` |
+
+That is one rule for both shapes the doc has to cover. In a **path**, `/` is a
+separator, so the first character of every segment is a word start: `foo` in
+`~/dev/foobar` starts a segment and outscores `foo` in `~/src/myfoo`, which
+starts nothing. In a **session name**, `-`, `_`, `.` and spaces do the same
+work, so `ws` reaches `web-search` more cheaply than `websearch`.
+
+### Score
+
+Let the query characters be matched at positions `p₀ < p₁ < … < pₘ₋₁`, and let
+`p₋₁ = -1`. For each matched character `i`, with `gap = pᵢ - pᵢ₋₁ - 1`:
+
+```
+contribution(i) = 16                      // every matched character
+                + bonus(pᵢ)               // the table above
+                + (gap == 0 ? +8          // adjacent to the previous match
+                            : -min(gap, 12))
+```
+
+`gap` for `i = 0` is the number of characters skipped before the first match, so
+a match that starts late is penalised exactly like an internal gap, and the cap
+is the same one.
+
+The **field score** is the sum of the contributions, plus at most one whole-field
+adjustment:
+
+- compact field text **equals** the normalized query → `+64`
+- else compact field text **starts with** the normalized query → `+32`
+
+Length is deliberately not in the score — it is a tie-break, so a long field
+never loses to a short one that matched worse.
+
+### Which embedding
+
+A query can sit in a field many ways. The one that counts is the
+**highest-scoring** embedding; among embeddings that score the same, the
+**leftmost** — compare position vectors element by element, smaller wins.
+
+Greedy leftmost-first matching is not sufficient and must not be used: in
+`maestro-tui`, `mtu` greedily takes `m₀ a₁ …` and never reaches `tui`. Both
+implementations use the obvious dynamic program over
+`(query index, text position)`, carrying the best score and its position
+vector, since the gap term depends only on the previous matched position.
+
+The whole-field adjustment is constant for a `(query, field)` pair, so adding it
+after the dynamic program cannot change which embedding wins.
+
+### Ordering
+
+Sort by score, highest first. Equal scores break in this order:
+
+1. **Kind** — `session`, then `command`, then `directory`.
+2. **Length of the matched field text**, shorter first.
+3. **The matched field text**, ascending, compared by code point, case
+   sensitive.
+4. **Input order.** The sort is stable, so candidates the caller ordered
+   deliberately — sessions most recently focused first, commands in registry
+   order — keep that order when nothing else separates them.
+
+Kind leads because that is the ruling the ambiguous cases need: a session named
+`kill` and the `kill` command that score alike put the session first, because
+the operator who typed a session's name meant the session.
+
+### Empty query
+
+A normalized query that is empty **matches every candidate**, each with score
+`0` and no ranges, in input order. The bar's own rules decide what is in the
+candidate list at that point (sessions only at the top level); the matcher does
+not filter by kind.
+
+## Fixtures
+
+These are the contract. Both matchers are tested against exactly these cases;
+the prose above is the explanation of why they come out this way.
+
+Candidates are written as `kind(fields)`; unlisted fields are absent.
+`session(name, dir, command, tool)`. Scores are shown for diagnosis — **the
+order is what is being asserted**, and an implementation that ranks correctly
+with different absolute numbers has still failed, because the numbers are how
+the next fixture stays predictable.
+
+### F1 — empty query keeps input order
+
+```
+query:      ""
+candidates: session("kill", "~/dev/api", "bash")
+            session("killer-app", "~/dev/killer-app", "claude --resume", "claude")
+            command("Kill selected session")
+expected:   session("kill")           score 0
+            session("killer-app")     score 0
+            command("Kill selected session")  score 0
+```
+
+Every candidate matches, in the order given. No ranges.
+
+### F2 — a session named `kill` against the `kill` command
+
+```
+query:      "kill"
+candidates: (as F1)
+expected:   session("kill")                   178   name
+            session("killer-app")             146   name
+            command("Kill selected session")  146   label
+```
+
+`kill` wins on the exact bonus. The other two **tie at 146** — both are a
+contiguous prefix match — and the kind tie-break puts the session first.
+
+### F3 — a fragment matching mid-segment inside a path
+
+```
+query:      "foo"
+candidates: directory("~/dev/foobar")
+            directory("~/src/myfoo")
+            directory("~/foo")
+expected:   directory("~/foo")         78   ranges [2,3,4]
+            directory("~/dev/foobar")  74   ranges [6,7,8]
+            directory("~/src/myfoo")   56   ranges [8,9,10]
+```
+
+The first two start a path segment; the third is mid-segment and loses by the
+whole boundary bonus. `~/foo` beats `~/dev/foobar` only because less was
+skipped before the match.
+
+### F4 — a query matching nothing
+
+```
+query:      "zzz"
+candidates: session("kill", "~/dev/api", "bash")
+            command("Kill selected session")
+expected:   (empty)
+```
+
+The matcher returns an empty list, never a list of zero-scored candidates. The
+bar renders its no-results state.
+
+### F5 — a non-contiguous subsequence
+
+```
+query:      "mtu"
+candidates: session("maestro-tui")
+            session("maestro-daemon")
+            session("mtui-scratch")
+expected:   session("mtui-scratch")  122   ranges [0,1,2]
+            session("maestro-tui")    91   ranges [0,8,9]
+```
+
+`maestro-daemon` has no `u` after its `t` and does not match. `maestro-tui`
+does, across a gap — which greedy matching would miss entirely.
+
+### F6 — a name beats a directory
+
+```
+query:      "api"
+candidates: session("api", "~/dev/web", "bash")
+            session("worker", "~/dev/api", "bash")
+expected:   session("api")     154   name
+            session("worker")   50   directory
+```
+
+The second session is found through its directory, and highlights there.
+
+### F7 — case-insensitive, tie broken by length
+
+```
+query:      "api"
+candidates: session("API-Gateway")
+            session("apiary")
+expected:   session("apiary")       122   name
+            session("API-Gateway")  122   name
+```
+
+Both are prefix matches and score identically. Same kind, so length decides:
+6 characters before 11. Input order does not save `API-Gateway`.
+
+### F8 — the tool field
+
+```
+query:      "claude"
+candidates: session("nameless", "~/dev/x", "claude --resume", "claude")
+            session("clay", "~/dev/y", "bash")
+expected:   session("nameless")  186   tool
+```
+
+`clay` has no `claude` subsequence anywhere and drops out. `nameless` matches
+its `tool` exactly (`+64`, weight `-40`, giving 186) which beats the prefix
+match on its `command` field (`+32`, weight `-32`, giving 162).
+
+### F9 — a word boundary inside a session name
+
+```
+query:      "ws"
+candidates: session("websearch")
+            session("web-search")
+expected:   session("web-search")  71   ranges [0,4]
+            session("websearch")   56   ranges [0,3]
+```
+
+The `s` after `-` earns the boundary bonus; the `s` inside `websearch` earns
+nothing.
+
+### F10 — command labels
+
+```
+query:      "se"
+candidates: command("Kill selected session")
+            command("Create a session")
+            command("Show help")
+expected:   command("Show help")             53   ranges [0,6]
+            command("Kill selected session") 51   ranges [5,6]
+            command("Create a session")      47   ranges [9,10]
+```
+
+`Show help` starts at position 0; the other two start at a word boundary but
+later, and pay for the skipped characters.
+
+### F11 — a query against session directories
+
+```
+query:      "dev"
+candidates: session("api", "~/dev/api", "bash")
+            session("notes", "~/documents/dev-notes", "nvim")
+            session("scratch", "~/srv/devops", "bash")
+expected:   session("api")      54   directory, ranges [2,3,4]
+            session("scratch")  50   directory, ranges [6,7,8]
+            session("notes")    44   directory, ranges [12,13,14]
+```
+
+All three start a path segment. They separate purely on how much was skipped
+first, and `notes` hits the `-12` gap cap.
+
+### F12 — exact beats prefix
+
+```
+query:      "quit"
+candidates: command("Quit Maestro")
+            command("Quit")
+expected:   command("Quit")           178   label
+            command("Quit Maestro")   146   label
+```
+
+The 32-point difference between the exact and prefix adjustments is the whole
+gap; nothing else about the two matches differs.

docs/INSTALL.md

@@ -18,10 +18,14 @@ wizard, and cleans up — only the unified `maestro` binary ends up persisted in
 
 **Updating is the same command.** Re-running `./install.sh` detects an existing
 systemd unit, refreshes it, and runs `systemctl --user restart maestro` instead
-of `start`. No `--update` flag needed. **The restart keeps your sessions:** the unit sets
+of `start`. No `--update` flag needed. **The restart keeps your terminal sessions:** the unit sets
 `KillMode=process`, so systemd signals only the daemon — the tmux server (and
-every session) survives, and the new daemon re-adopts them on start. A unit
-written before this default lacks the line; re-run `./install.sh` to refresh it.
+every tmux-backed session) survives, and the new daemon re-adopts them on
+start. Structured sessions (an agent run as a daemon child over ACP) are not
+tmux panes, so shutdown ends their active turn; the transcript survives and
+the next daemon attempts one resume (`docs/RESTART.md#structured-sessions`). A
+unit written before this default lacks the line; re-run `./install.sh` to
+refresh it.
 
 Inside the script, `cargo install --git https://git.naps.pt/naps62/maestro …`
 uses your already-configured git credentials for this host (HTTPS helper or
@@ -94,7 +98,10 @@ running a local daemon, for a host that only talks to another machine's.
 
 The daemon unit carries the same `KillMode=process` as the wizard-written one,
 so `systemctl --user restart maestro-daemon` leaves the tmux server and every
-session alive.
+terminal session alive. Structured sessions end their active turn on
+shutdown and resume once on the next daemon: ACP state comes back via
+`session/load`, while the event log only replays Maestro's own transcript
+projection (`docs/RESTART.md#structured-sessions`).
 
 ## Thin builds for single-role hosts
 
@@ -136,12 +143,14 @@ cover every v1 action — only override what you want to change:
 ```toml
 [tui]
 theme = "dark"              # see the theme list below
-leader = "ctrl-a"            # one byte that escapes Insert mode
+leader = "ctrl-a"            # one byte that escapes Insert mode; the web reads
+                             # the same setting off /api/info
 chord_timeout_ms = 1000      # how long to hold a partial chord like `ctrl-w`
 
 [tui.keymap.normal]
 "i"            = "EnterInsert"
-"s"            = "OpenSpawnModal"
+"n"            = "OpenSpawnModal"
+"N"            = "FastForwardSpawn"
 "x"            = "KillHighlighted"
 "r"            = "RenameHighlighted"
 "?"            = "ShowHelp"
@@ -186,6 +195,34 @@ An unknown name is rejected as an `[tui].theme` configuration error.
 The full action vocabulary is the `Action` enum in
 `crates/maestro-tui/src/action.rs`.
 
+## Structured sessions: `claude-code-acp`
+
+A session spawned with `view: Structured` (#134) runs Claude Code as a child
+of the daemon over the Agent Client Protocol instead of in a tmux pane. The
+daemon resolves the adapter binary, `claude-code-acp`, on its `PATH` at spawn
+time. Install it once per host:
+
+```sh
+npm install -g --prefix ~/.local @zed-industries/claude-code-acp
+```
+
+That puts `claude-code-acp` in `~/.local/bin`, which must be on the daemon's
+`PATH` (a systemd user unit does not read your shell profile; set
+`Environment=PATH=…` in the unit or install somewhere already on it). The
+adapter needs a logged-in Claude Code (`claude /login`).
+
+When the adapter is missing the spawn still creates the session, marked dead
+with the install command above as its activity detail, so the sidebar says
+what to run. The adapter is a child of the daemon: it ends with a `DELETE
+/api/sessions/:id` (`session/cancel`, then `SIGTERM`) and with the daemon
+itself. A daemon restart ends an in-flight structured turn, but preserves its
+worktree, session record, and event-log transcript. The replacement daemon
+starts a new adapter, resumes it with `session/load`, and replays the
+transcript. Terminal sessions keep surviving restarts through tmux. See
+`docs/STRUCTURED-VIEW.md` for the full contract — row kinds, projections, the
+handshake, and the approval and recovery rules — and `docs/RESTART.md` for
+what a client observes across the restart.
+
 ## The browser UI
 
 The daemon serves the SPA off its own listener. Open

docs/PREVIEW.md

@@ -0,0 +1,103 @@
+# PREVIEW.md — the sidebar preview contract
+
+One rule for what the content pane shows while the operator is only moving
+around the sidebar, so the web client and the TUI behave the same. Read this
+before changing either. If the behaviour needs to change, change it here first.
+
+## The rule
+
+Highlighting a session in the sidebar shows that session in the content pane,
+as if it were focused, **without focusing it and without changing the layout**.
+Moving the highlight elsewhere puts back exactly what was on screen before.
+
+A preview is a view, not a state. Nothing about it is durable:
+
+- The layout is byte-for-byte identical before the preview and after it ends.
+- Nothing is persisted while a preview is up (the web client's layout is saved
+  to `localStorage`; a preview never reaches it).
+- The daemon is never told the previewed pane is focused, so a preview never
+  clears a session's `AwaitingInput` glow (`docs/SIDEBAR.md`).
+- The keyboard stays in the sidebar: the previewed terminal is on screen but
+  does not take focus, so the next `j`/`k` still walks the list.
+
+## Where the preview is shown
+
+| The previewed session is… | What happens |
+|---|---|
+| Already in a pane, in the active tab | That pane comes forward (its tab's focus moves to it). |
+| Already in a pane, in another tab | That tab is brought forward. The active tab is restored when the preview ends. |
+| Not in any pane | A throwaway tab carries it. It is removed when the preview ends. |
+
+The throwaway tab never counts as an open session: the tab bar does not appear
+because of it, the mobile shell does not switch away from the session list for
+it, and the sidebar does not mark the session as open.
+
+## How a preview reads
+
+A preview is provisional, so it never wears the accent — the accent is what
+says "this is the one you picked". It has a hue of its own, and every surface
+involved in the preview carries that same hue, so the pane and the row it came
+from read as one thing rather than two unrelated highlights.
+
+Web client (`--preview` and friends in `web/src/styles.css`):
+
+| Surface | While previewing |
+|---|---|
+| The previewed pane's titlebar | Tinted in the preview hue, at full strength, in place of the focused pane's accent tint. |
+| The canvas | A `preview` chip, top right, and a dashed inset ring. |
+| A throwaway tab | Dashed border, italic label. |
+| The sidebar row being previewed | Filled with the preview hue, over whatever open state the row already had — but the row of the session already showing in the pane keeps its accent fill, since previewing it changes nothing on screen. |
+| The sidebar row of the session the operator picked | Keeps its accent fill for the whole preview. A preview never moves the accent; only opening another session does. |
+| A hovered sidebar row, and the keyboard cursor on a session | A lighter wash of the same hue, because both are what previews a row. |
+
+Rows say it with fill, not with an edge — see the tier ladder in
+`docs/SIDEBAR.md`, which previewing sits at the bottom of. The dashed edges
+belong to the pane: the canvas ring and the throwaway tab.
+
+The hue is a palette token, not a fixed colour: a palette whose accent already
+sits on it moves it (`--preview-h`), so "previewing" and "picked" never collide.
+
+The TUI marks a preview in text only — the title bar reads `<name>  ·  preview`
+— and has no preview colour role yet.
+
+## What ends a preview
+
+- The highlight moves to another session — that session is previewed instead.
+- The highlight leaves every session (a folder row, or the list losing the
+  keyboard, or the pointer leaving the list): the previous view comes back.
+- Any real layout change (split, close, new tab, tab switch, drag): the preview
+  is discarded first, so a throwaway tab is never baked into the arrangement.
+
+## What commits a preview
+
+Choosing the previewed session — clicking or pressing Enter on its row,
+clicking into its pane, or handing the keyboard to the pane (web: `Tab` from
+the list; TUI: the attach binding) — keeps exactly what is on screen. A
+throwaway tab becomes a real one; a focus move inside an existing tab stands.
+Nothing moves a second time on commit.
+
+## Timing
+
+**A preview is never delayed.** Landing on a row — by pointer or by `j`/`k` —
+shows it on the next frame, and so does leaving every row. There is no
+settling period in front of the first preview, because that period would sit
+in front of the one preview the operator actually meant.
+
+What is bounded is how *often* the pane may swap: at most once per 120 ms.
+A burst inside one window — `j` held down, or the pointer sweeping the length
+of the sidebar — shows the row it started on, then the row it ended on, and
+none of the rows in between. So a walk costs a couple of pane mounts rather
+than one per row, without the operator ever waiting on one.
+
+The highlight itself is not bounded by any of this: the row lights up on the
+same frame as the input, whatever the pane behind it is doing.
+
+Touch has no hover, and a tap already opens a session, so touch never previews.
+
+## Cost
+
+A previewed session that no pane holds needs a live attach. Both clients keep
+it connected after the preview ends — the web client parks it in the connection
+pool's LRU, the TUI keeps its emulator until it falls out of the preview
+budget — so stepping back onto a row is instant rather than re-fetching
+scrollback.

docs/RESTART.md

@@ -2,10 +2,16 @@
 
 Maestro is upgraded in place: the operator reinstalls the binary and systemd
 restarts the daemon under every browser tab and TUI that is attached to it.
-tmux keeps the sessions alive across that (see `docs/INSTALL.md`), but clients
-lose their sockets. This document is the contract for what a client does about
-it — what the daemon publishes, how a client tells a restart from a blip, and
-what the user sees while it happens.
+tmux keeps **terminal** sessions alive across that (see `docs/INSTALL.md`),
+but clients lose their sockets either way. This document is the contract for
+what a client does about it — what the daemon publishes, how a client tells a
+restart from a blip, and what the user sees while it happens.
+
+A **structured** session (`docs/STRUCTURED-VIEW.md`) has no tmux pane behind
+it to survive on: its agent is a child of the daemon process itself, so a
+restart takes it down with the daemon. See
+[Structured sessions](#structured-sessions) below for exactly what that
+costs and what it doesn't.
 
 ## What the daemon publishes
 
@@ -68,6 +74,35 @@ resolves, so a blocked client is never a trapped one. It clears itself the
 moment a probe succeeds — there is no "retry" button, because the client is
 already retrying.
 
+## Structured sessions
+
+Everything above describes a **client's** view of a restart, and it holds for
+a structured session exactly as written — the same three verdicts, the same
+status indicator, the same overlay. What differs is what survives on the
+**daemon** side, because a structured session's agent is a daemon child, not
+a tmux pane:
+
+- A restart **ends the active turn**. There is no adapter process left to
+  finish it, and no tmux pane keeping it alive underneath.
+- The **transcript survives**, in the per-session event log
+  (`docs/STRUCTURED-VIEW.md#persistence-recovery-and-dead-sessions`) — a
+  graceful shutdown marks the session for one resume attempt. Recovery is
+  two separate operations, not one: the next daemon calls `session/load` so
+  the adapter restores its own ACP session, but whatever history the
+  adapter emits during that call is discarded, not replayed into anything —
+  the daemon already has that history on disk. Separately, the daemon
+  rebuilds its own projection by folding the persisted event log back
+  through it. An ungraceful death (a crash, `kill -9`) leaves no resume
+  marker, and the session stays dead permanently.
+- **Pending approvals and their nonces do not survive.** Both live only in
+  the old daemon's memory; any ACP permission request still mid-flight when
+  the daemon exits is answered `Cancelled` on the way down, and a resumed
+  session starts with no pending approval at all.
+
+`docs/STRUCTURED-VIEW.md` is the full contract for all of this — the event
+log's shape, the recovery marker, and exactly which kind of session death is
+resumable.
+
 ## Timing
 
 - **Grace window** — 1200 ms between the socket dropping and the overlay

docs/SIDEBAR.md

@@ -177,6 +177,38 @@ surface; a colour chosen for the card background is never painted onto the
 selection background. Contrast is a property of the palette (values are RGB)
 and is asserted in the palette's tests, not left to the terminal theme.
 
+## Which row is filled
+
+Both clients say every one of these with a **background fill**, never an edge.
+A row is usually several of them at once, so they form a ladder: the tier
+furthest down wins the paint.
+
+| Tier | Web | TUI |
+|---|---|---|
+| Alive | 6% accent wash | — (the rail carries it) |
+| Under the pointer or the keyboard walk | preview hue, light | selection surface, while the sidebar holds the keyboard |
+| Open in some pane, not the focused one | 6% accent wash (`.is-open`) | — (the `●` glyph carries it) |
+| Showing in the pane | `--accent-fill` | `pane_row_bg()` — partway from the card surface to the selection surface |
+| Previewing (`docs/PREVIEW.md`), unless that row is the one showing in the pane | `--preview-tint` | — (no preview colour role yet) |
+
+The web ladder is written as one ordered run of equal-specificity rules in
+`styles.css`, every qualifier inside `:where()`, so the order they appear in
+*is* the precedence. Add a tier where it belongs in that run, never by piling
+on another class to out-weigh the rule above it.
+
+The TUI's two filled tiers both carry the **selection** surface's foregrounds,
+since those are the colours picked for a filled row. `pane_row_bg()` is
+blended from the two surfaces rather than shipped as a third one — a third
+surface would mean eight more colours hand-picked seventeen times — and the
+palette tests assert it stays a visible step from both. The cursor's fill wins
+on its own row, so a highlight parked on the session already in the pane is
+still visible.
+
+The one edge left in either list is the TUI's `▏` marker, which stands in for
+the cursor's fill while the pane holds the keyboard, and the web's ring on a
+highlighted **folder** row — a folder previews nothing, so it has no fill to
+step up to.
+
 The duration text inherits its state's colour; the exited and command
 fragments use the surface's `muted` role, as do the diff stat's `~`, `?` and
 `↑` fragments. Only `+` and `-` step outside the surface's muted role, and they
@@ -199,7 +231,24 @@ cutover points land within one tick.
 
 ## Precedence
 
-An agent-reported `ActivityState` (#105) overrides the daemon's inference for
+### Activity source by session kind
+
+The daemon supplies one `activity` field to both clients, but its source depends
+on the session kind:
+
+| Session kind | Source |
+|---|---|
+| Terminal | The existing agent-report override and five-minute TTL, falling back to PTY quiescence, foreground process and `/proc` input-block inference. |
+| Structured | ACP state directly: a pending approval is `AwaitingInput`; otherwise an in-flight turn is `Active`; no turn is `Idle`. A failed turn or dead structured session is `Error`, and the next turn clears a failed-turn error. |
+
+Structured sessions never enter the terminal inference path and ignore activity
+reports inherited through agent hooks. They have no PTY whose output or blocked
+read could describe their state. This is a second source, not a replacement for
+the terminal source.
+
+### Terminal report override
+
+For terminal sessions, an agent-reported `ActivityState` (#105) overrides the daemon's inference for
 **five minutes** (the TTL is fixed by the daemon; re-reporting extends it).
 When the TTL expires, inference resumes and the session's reported detail —
 if any — clears with the report. Clients never blend the two: whichever source
@@ -218,6 +267,10 @@ Two rulings specific to a reported `Error` (#114):
   process changes do not clear it — only the agent itself may withdraw what
   the agent itself reported. Re-reporting `Error` extends the TTL rather than
   stacking reports.
+- **Only Claude Code reports `Error`.** Codex has no counterpart to
+  `StopFailure` in its hook event set, so a codex turn that ends on an API
+  error reports `AwaitingInput` and its card carries no error mark. A card
+  without the mark means "nothing reported a failure", not "nothing failed".
 
 If a client receives an `ActivityState` variant it does not know, it must not
 fail rendering: treat it as `Idle` (neutral/dim, line-2 rules apply as usual)
@@ -245,10 +298,10 @@ session is genuinely `Active` again — new work, not merely a refocus. Only
 after that fresh `Active` cycle does the *next* `AwaitingInput` glow again.
 Unfocusing and refocusing alone never re-arms it.
 
-This applies uniformly to `AwaitingInput` from either source — the daemon's
-own inference or an agent's report (#105) — since the rail draws them
-identically. It does not touch `Error`; that state's own TTL (below) is
-unrelated and unaffected by focus.
+This applies uniformly to `AwaitingInput` from terminal inference, an agent
+report (#105), or a structured session's pending approval, since the rail draws
+them identically. It does not touch `Error`; terminal reports keep their TTL,
+while a structured failed-turn error clears when the next turn starts.
 
 Each client reports its own pane's focus with `POST /api/sessions/:id/focus`
 (`{"focused": bool}`) whenever the pane it is showing changes — on attach, on
@@ -271,6 +324,40 @@ lands on the first row it was hiding. A highlight parked on a skipped row —
 reachable by clicking a folder header — still steps to its neighbour rather
 than jumping to the end of the list.
 
-The web client needs a chord to reach the list at all (`Ctrl+Shift+H`, and the
-same chord back): an attached terminal owns every plain keystroke. The TUI uses
-`ctrl-w h`.
+The web client needs a chord to reach the list at all (leader-`h` — `Ctrl+A h`
+by default — and the same chord back): an attached terminal owns every plain
+keystroke, and Escape is left to reach the pane's shell/app instead. The TUI
+uses `ctrl-w h`.
+
+Everything else is the same key on both clients:
+
+| key     | action                                      |
+|---------|---------------------------------------------|
+| `j`/`k` | move the highlight (arrows too)             |
+| `Enter` | open the session, or expand the folder      |
+| `Tab`   | hand the keyboard to the pane               |
+| `c`     | collapse or expand the highlighted folder   |
+| `r`     | rename the highlighted session              |
+| `x`     | kill the highlighted session (confirms)     |
+| `n`     | open the spawn form                         |
+| `N`     | spawn with every default resolved           |
+| `?`     | show the shortcut overlay                   |
+
+The TUI binds these through its keymap, so a user can rebind any of them; the
+web client's are fixed. A binding added to one client belongs in this table and
+in both help overlays.
+
+## Killing a session
+
+**Every kill confirms first, in both clients** (#160). A kill is destructive
+and unattended agents live in these sessions, so neither client sends
+`DELETE /api/sessions/:id` off a single press. The TUI raises
+`OverlayKind::KillConfirm` (`[y]`/`[n]`); the web raises the same dialog its
+`✕` button and the command bar's action page both use. Cancel holds the focus
+in the web's dialog, so nothing kills on a stray Enter.
+
+The confirmation names what the card last saw in the way, when anything was —
+the daemon will refuse an unforced kill over such a worktree, and saying so
+before the attempt is cheaper than a refusal. What comes back from that refusal
+is a second, separate prompt offering `force=true`; `docs/WORKTREES.md` owns
+what a forced kill leaves behind.

docs/STRUCTURED-VIEW.md

@@ -0,0 +1,389 @@
+# STRUCTURED-VIEW.md — the structured session contract
+
+The contract for a structured session (`view: Structured`, #133): an agent run
+as a daemon child over the Agent Client Protocol (ACP) instead of in a tmux
+pane. Alongside `docs/WORKTREES.md`, `docs/SIDEBAR.md` and `docs/RESTART.md`,
+read this before changing anything that renders a structured session — both
+the web and TUI renderers are written against it.
+
+It covers the eight transcript row kinds, what the daemon decides versus what
+a client decides, the two projections and their delta/cursor semantics, the
+ACP handshake and the capabilities it declines, the adapter's install
+command, and the approval nonce rules. **Non-goal: the detached runner.** It
+does not exist yet, and nothing here describes it.
+
+## What a structured session is
+
+A terminal session's agent runs inside a tmux pane; a structured session's
+agent runs as a subprocess of the daemon itself, speaking ACP over stdio. The
+daemon is the ACP **client**; the adapter process, `claude-code-acp`, is the
+ACP **agent** — it wraps Claude Code's own SDK and translates the model's
+tool calls into ACP `session/update` notifications instead of drawing them to
+a pane. `crates/maestro-acp` owns the daemon's side of that connection;
+`crates/maestro-daemon/src/projection.rs` folds what it receives into the two
+projections below.
+
+The child is a real child of the daemon process: same process group, and on
+Linux marked with `PR_SET_PDEATHSIG` so it dies with the daemon even if the
+daemon exits without cleaning up; other platforms have no such signal and
+depend on an orderly shutdown/drop to terminate it. The ordinary path on
+every platform is `AcpSession::terminate` (`session/cancel`, a short grace,
+`SIGTERM`, then `SIGKILL`), called from both `DELETE /api/sessions/:id` and
+daemon shutdown.
+`docs/WORKTREES.md`'s kill-guard rule — an unforced kill refused while the
+session's worktree holds unsaved work — applies to a structured session
+exactly as it does to a terminal one; only what gets terminated differs (an
+ACP handle instead of a tmux pane).
+
+## The adapter
+
+`ADAPTER_BIN` (`claude-code-acp`) is resolved by walking `PATH` — the
+session's own `PATH` env var if the spawn request set one, the daemon's
+otherwise — and taking the first executable file named `claude-code-acp` on
+it. Install it once per host:
+
+```sh
+npm install -g --prefix ~/.local @zed-industries/claude-code-acp
+```
+
+That is `maestro_acp::INSTALL_COMMAND`, and it is not just documentation: it
+is baked into `AcpError::AdapterMissing`'s message. When the adapter cannot
+be found, spawn still creates the session — **Dead**, with that install
+command as its `activity_detail` — so the sidebar names the fix instead of
+the session silently never appearing (see `docs/INSTALL.md` for the full
+install writeup, including the systemd `PATH` caveat). The adapter also needs
+a logged-in Claude Code (`claude /login`); a missing login surfaces the same
+way, via the adapter's own stderr tail in the failure message.
+
+The handshake is bounded by `HANDSHAKE_TIMEOUT` (60s) — long enough for a
+slow machine to boot a node process and the Claude Code SDK behind it, never
+long enough to hang a spawn indefinitely. Any handshake failure — missing
+adapter, early exit, a protocol error, or the timeout — leaves no orphaned
+process: `spawn` closes and reaps the child itself before returning the
+error.
+
+## The ACP handshake
+
+`initialize` is where the daemon states what kind of client it is. It
+declares, deliberately, almost nothing:
+
+| Capability | Declared | Why |
+| --- | --- | --- |
+| `fs.readTextFile` | `false` | The adapter uses Claude Code's own Read tool instead of asking the daemon to read a file on its behalf — the same tool a terminal-view Claude Code session uses. |
+| `fs.writeTextFile` | `false` | Same reasoning, for Write. |
+| `terminal` | `false` | The adapter runs Claude Code's own Bash tool rather than asking the daemon to open a terminal for it. |
+
+Declining all three keeps the daemon out of the file/terminal surface
+entirely — the adapter already has direct access to the session's `cwd`, and
+routing every read, write, and shell command through the daemon would only
+add a hop with no new capability. Every other capability namespace ACP
+defines (session extensions, auth, elicitation) is simply left at its
+default; the daemon does not advertise support because `claude-code-acp` has
+never asked for it, not because it was weighed and refused.
+
+The one client method that *is* implemented for real is
+`session/request_permission` (#139) — see [Approvals](#approvals) below.
+Before #139 it was a stub that declined every request; that stub is gone now
+that a live implementation exists.
+
+`session/new` opens a fresh ACP session on every ordinary spawn. A respawn
+after a daemon restart instead sets `SpawnConfig::load_session(id)` and runs
+`session/load` with the ACP session id the original handshake returned
+(`Session::acp_session_id` on the wire) — the adapter must advertise
+`agent_capabilities.load_session`, or the handshake fails outright naming
+that. Whatever history the adapter streams back while `session/load` is in
+flight is dropped on arrival, deliberately: the daemon's own event log
+already holds that history, and forwarding it too would duplicate every row
+in the projections below.
+
+## The eight transcript row kinds
+
+`TranscriptRowKind` (`maestro-protocol`) is the alphabet a structured
+transcript is written in. Every row has a stable `id` (so later deltas can
+address it), a `kind`, and a `data: Value` that preserves the underlying ACP
+payload — clients depend on ACP's *shape* without depending on ACP as a
+crate.
+
+| Kind | Carries | Row identity |
+| --- | --- | --- |
+| `User` | An echoed `user_message_chunk` — the prompt text as ACP saw it. | `user:<message_id>`, or `user:<seq>` when the chunk carries no id. |
+| `AgentText` | An `agent_message_chunk` — the agent's visible reply, streamed. | `agent:<message_id>` / `agent:<seq>`. Later chunks for the same id are appended into `data.content.text` in place, not appended as new rows. |
+| `AgentThought` | An `agent_thought_chunk` — the model's reasoning stream. | `thought:<message_id>` / `thought:<seq>`, coalesced the same way as `AgentText`. |
+| `ToolCall` | A `tool_call` / `tool_call_update` pair whose content carries no diff. | `tool:<tool_call_id>` — one row for the call's whole life; updates patch it in place, they never create a second row. |
+| `ToolDiff` | The same tool-call machinery, when the tool's content includes a `Diff` block. | Same `tool:<tool_call_id>` identity as `ToolCall`; the *kind* flips between the two as the tool's own content changes, not the row. |
+| `Approval` | A daemon-originated permission request (`RequestPermissionRequest`), serialized without its nonce. | `approval:<uuid>` — minted fresh per request, unrelated to the ACP request's own id. |
+| `Plan` | A `plan` update — the agent's current step list. | The fixed id `"plan"`. Each new plan **replaces** the row wholesale; entries are not diffed against the previous plan. |
+| `Notice` | The raw JSON of any `session/update` variant the ACP dependency already decodes but the projection does not special-case. | `notice:<seq>`. |
+
+`Notice` covers known-but-unspecialized `SessionUpdate` variants: ones the
+`agent-client-protocol` dependency's schema already deserializes (it
+currently folds `available_commands_update` and `session_info_update`
+there) but the projection's `match` doesn't fold into one of the other
+seven kinds. It is not a wire-level forward-compatibility seam:
+`SessionUpdate` is an internally-tagged enum with no unknown-variant
+fallback, so a `session/update` whose `sessionUpdate` tag this build's
+dependency has never heard of — including a variant gated behind an
+unstable ACP feature this build doesn't enable, which is compiled out of
+the enum entirely — fails to deserialize before the projection ever runs,
+rather than becoming a `Notice`. A genuinely new ACP variant needs the
+`agent-client-protocol` dependency upgraded (and, typically, the projection's
+`match` taught about it) before it can appear on this transcript at all — see
+`projection.rs`'s test asserting that an unrecognised `sessionUpdate` tag is a
+deserialization error, not a `Notice`. A client that does not know what to do
+with a `Notice` can still render it as an opaque, collapsed line — that
+remains a reasonable floor, not a client bug.
+
+Rendering is entirely a client concern. The projection's job stops at
+folding ACP into these eight shapes; markdown formatting, diff rendering,
+tool-card treatment, and how a `Notice` is presented are all renderer
+choices, not daemon ones.
+
+## Daemon decisions vs. client decisions
+
+**The daemon decides:**
+
+- Which ACP `session/update` becomes which row kind, and under what id — the
+  fold in `projection.rs` is the one place this logic lives, so the web and
+  TUI renderers can never disagree about it.
+- Turn lifecycle: when a turn begins, and whether an ACP response, a cancel,
+  or a failure ends it (`TurnState.responding` / `.thinking` /
+  `.active_tool_calls` are derived, not renderer-computed).
+- Approval nonce minting, secrecy, and the single-active-approval rule (see
+  below) — a client never sees an ACP permission request before the daemon
+  has already turned it into an `Approval` row and a nonce.
+- What happens to an ACP update variant the dependency decodes but nobody has
+  taught the projection to special-case (falls back to `Notice` rather than
+  erroring). A variant the dependency itself can't decode is a deserialization
+  error, not a `Notice` — see [The eight transcript row
+  kinds](#the-eight-transcript-row-kinds).
+- Persistence and replay: what is written to the event log, in what order,
+  and how a restart resumes it.
+
+**A client decides:**
+
+- How each row kind is drawn — markdown for `AgentText`/`AgentThought`, a
+  diff view for `ToolDiff`, a tool card for `ToolCall`, and a floor
+  presentation for `Notice`. `Plan` is the exception: both clients omit it
+  from the transcript entirely and render the current plan in a separate
+  plan rail (web) / status line (TUI) instead.
+- How `responding` vs. `thinking` are distinguished visually, if at all.
+- How the operator is asked to resolve an `Approval` row — the daemon only
+  exposes the three-way decision (`AllowOnce` / `AllowForSession` / `Deny`),
+  never the UI that solicits it.
+- Scrolling, collapsing, and every other presentation-only behaviour.
+
+## The two projections
+
+`Projection` (daemon-only) is folded once from the durable ACP stream and
+exposes two independent views, both defined in `maestro-protocol`:
+
+- **`TranscriptSnapshot { cursor, rows }`** — the complete ordered list of
+  transcript rows built so far, plus the log position (`cursor`) it reflects.
+  It is intentionally always the *whole* transcript, not a windowed one: a
+  tool row patched much later must still find its original entry.
+- **`ReducedState`** — one whole-session snapshot folded over every event
+  seen: `turn` (the per-turn indicators above), `pending_approval`, `plan`,
+  `usage`/`context`, `model`, and `mode`. Like `TranscriptSnapshot`, it is
+  always full-history, never a delta — a client that only wants "is a turn
+  active right now" never has to replay anything to answer that.
+
+Changes to the transcript travel as `TranscriptDelta`, tagged `type`:
+`Append { row }` (a new row), `Patch { row }` (an existing row, addressed by
+`id`, replaced wholesale), and `Remove { id }`. `Remove` is defined on the
+wire for forward compatibility; nothing in the current projection emits it —
+every row, once appended, is only ever patched or left alone.
+
+### Cursor and replay semantics
+
+The event log's own line position is the cursor: 1-based, shared by ACP
+notifications and daemon-generated rows alike (`sidecar.rs`'s
+`PersistedEvent` envelope is what lets an `Approval` row share a cursor
+sequence with raw ACP JSON without pretending to be ACP traffic). Two ways to
+read it:
+
+- **`WS /api/structured/:id`** — on connect, sends a `TranscriptSnapshot` and
+  a `ReducedState` covering the whole log as it stands, then streams
+  `ProjectionUpdate { transcript, state }` for everything that happens next.
+  There is no client-supplied resume cursor on this socket: every connection
+  gets the full snapshot, not a gap-filled continuation, so a client never
+  needs the replay endpoint just to obtain the current transcript. Use
+  replay instead for cursor-bounded pagination through the durable log —
+  history from before this connection, fetched a page at a time.
+- **`GET /api/sessions/:id/structured/replay`** — cursor-bounded pagination
+  over the durable log, returning one `StructuredReplayEvent` (`cursor`,
+  `transcript`, `state`) per matching line. `?since=<n>` returns the first
+  page after `n` (`since=0` selects from the beginning, i.e. the first
+  page); a client pages forward from there using the cursor of the last
+  event returned. `?before=<n>` returns the page immediately before `n`,
+  still in ascending order — passing both is a `400`. `?limit` defaults to
+  100 and is clamped to 500. Each call re-folds
+  the entire log from scratch to compute the state at every returned cursor,
+  so a page reflects exactly the *durable* state at its cursor, not an
+  approximation of it — at the cost of redoing the whole fold per request.
+  That durable state is not always identical to what a live client saw at
+  that moment, though: turn lifecycle transitions are broadcast live without
+  a durable event backing them (see [Prompt and cancel](#prompt-and-cancel-bounded-liveness)),
+  and a restored `Approval` row carries no pending nonce, because the nonce
+  never reached disk (see [Approvals](#approvals)) — replay is exact and
+  reconstructible, not a perfect record of everything the live view showed.
+  A session that is not a live structured session (terminal, or a dead
+  adapter) answers `409 not_structured` from either route rather than a
+  coherent-looking but stale reply.
+
+## Approvals
+
+An ACP `session/request_permission` callback becomes an `Approval` row plus a
+pending decision, entirely on the daemon side:
+
+- **Generation.** The daemon mints the nonce itself — a fresh
+  `Uuid::new_v4()` string per request — rather than using anything ACP's own
+  request carries. ACP permission callbacks have no request id of their own
+  that would double as one.
+- **Live-only placement.** The nonce lives in exactly one place: the
+  in-memory `pending_approvals` map keyed by nonce, and its mirror in
+  `ReducedState.pending_approval.nonce` on the live wire. It is never part of
+  the `Approval` row's `data` — the row is `RequestPermissionRequest`
+  serialized *without* the nonce.
+- **Secrecy from the agent and from durable history.** The adapter itself
+  never learns the nonce — it is a daemon-to-client secret, never sent back
+  over the ACP connection. It is likewise never written to the event log:
+  restoring an `Approval` row from disk (`Projection::restore_approval`)
+  produces a historical row with no `pending_approval` in state, because the
+  nonce that would make it "pending" never made it to disk in the first
+  place. A restart therefore cannot resume a pending approval — see
+  [Persistence](#persistence-recovery-and-dead-sessions).
+- **One live approval at a time.** A new permission request mints its own
+  nonce, then cancels whatever was already pending (`cancel_pending_approvals`)
+  before installing itself as the new pending approval — ACP serializes
+  requests through one connection, so this only ever fires if an adapter
+  nonetheless overlaps two. Either way, the prior pending request is
+  cancelled/cleared before the new one is installed, so the newest request
+  wins.
+- **Single-use and duplicate resolution.**
+  `POST /api/sessions/:id/structured/approvals/:nonce` **always answers
+  `204`** for a known, live structured session — whether the nonce is the
+  one currently pending, one already consumed by an earlier answer, or one
+  that never existed. Only an unknown or non-structured *session* answers
+  otherwise (`404` / `409`). This is deliberate: two clients racing to answer the same
+  approval must not turn a harmless duplicate click into a client-visible
+  error. Whichever `POST` reaches the daemon first removes the nonce from
+  `pending_approvals` and is the one whose decision actually reaches the
+  adapter; every later `POST` for that nonce is a no-op `204`.
+- **Cancellation vs. denial.** A turn cancel or a session shutdown resolves
+  any pending approval with ACP's `Cancelled` outcome, not a `Deny` decision
+  — the adapter should read those as "the operation was withdrawn," not "the
+  operator refused it."
+- **Decision mapping.** `AllowOnce` and `AllowForSession` select the ACP
+  option of kind `AllowOnce` / `AllowAlways` from the request's own option
+  list. `Deny` prefers a one-shot refusal (`RejectOnce`) and falls back to a
+  permanent one (`RejectAlways`) only when that is the sole rejection option
+  offered; if neither is present, it answers `Cancelled`.
+
+## Prompt and cancel: bounded liveness
+
+`POST /api/sessions/:id/structured/prompt` and `.../cancel` are serialized
+against each other through one per-session `operation` lock
+(`AcpEventStream::operation`), because ACP permission callbacks carry no
+per-request id — the daemon's own notion of "the active turn" is the only
+thing a callback can be attributed to, so at most one turn may ever be
+in flight, and a cancelled turn must fully settle before the next prompt is
+allowed to claim the daemon's idea of "the active turn."
+
+- A prompt claims the turn and dispatches it to ACP as one operation. While a
+  turn is active, a second prompt gets `409 turn_in_flight` rather than
+  queuing — one active turn per session, never a hidden queue of prompts.
+- Cancel sends `session/cancel`, clears any pending approval as `Cancelled`,
+  and ends the turn's client-visible lifecycle immediately. If the cancelled
+  turn was still *dispatched* to ACP (waiting on its response), the daemon
+  cannot simply forget it: ACP has not confirmed the cancel yet, and a new
+  prompt claiming "the active turn" while the old one is still outstanding
+  would make the next permission callback ambiguous between the two.
+- So a cancelled-but-still-dispatched turn must **settle within
+  `CANCEL_GRACE` (500ms)** — either ACP acknowledges the prompt (however it
+  resolves) or that grace period runs out. If it settles in time, the next
+  prompt proceeds normally. If it does not, the daemon does not guess: it
+  marks the whole structured session dead (`fail_cancelled_acp_turn`) rather
+  than risk a callback resolving against the wrong turn. This is the bounded
+  half of "bounded liveness" — a structured session's prompt/cancel dance
+  either resolves promptly or the session is declared unusable, never left
+  in an indefinite ambiguous state.
+
+## Persistence, recovery, and dead sessions
+
+A structured session's durable state is three files in the sidecar
+directory: the sidecar itself (`<id>.json`), plus two next to it:
+
+- **`<id>.events.jsonl`** — the unified event log. Each line is either a raw
+  ACP `SessionNotification` (kept in its original JSON so old logs stay
+  readable) or a `{"maestroEvent": "approval", "row": …}` envelope for a
+  daemon-generated row. Both share the same 1-based line-position cursor. A
+  line a hard kill left half-written is terminated before the next append, so
+  it keeps its position and is skipped as malformed rather than corrupting
+  what follows. An append that fails *while the daemon is running* — a
+  `write_all` that errors after only a prefix reached disk, or a `flush` that
+  errors after a complete write — is rolled back to the exact byte length the
+  file was at before the call, so `last_seq` and the file's line count never
+  disagree and the same log handle can be appended to again immediately (#184).
+  If that rollback itself cannot restore the prior length, the append is
+  fatal: the log's consistency can no longer be promised, so the caller kills
+  the session instead of appending to it again.
+- **`<id>.recover`** — an empty marker file. Its only meaning is "the daemon
+  that wrote this shut down gracefully while this session was running, and
+  the next daemon may attempt to resume it." It is consumed (deleted) the
+  moment a recovery attempt reads it — one recovery attempt per graceful
+  shutdown, never a standing flag.
+
+Three ways a structured session ends up `Dead`, each with different
+persistence consequences:
+
+1. **The adapter exits, or a notification append to the event log fails,
+   while the daemon keeps running.** (An approval-row append failure is
+   narrower: as long as the log rolled back cleanly, it only cancels the
+   pending approval and rolls the unpersisted `Approval` row back out of the
+   live transcript, without marking the session dead — a snapshot taken after
+   the failure must never show a row durable replay could not reproduce
+   (#184). If the rollback itself did not restore the log's prior length,
+   this narrower path does not apply either: the session is marked dead the
+   same as any other append failure, since the log can no longer promise
+   `last_seq` matches its file.)
+   `mark_session_dead` applies the same natural-exit worktree rule
+   as a terminal session's own pane exiting (`docs/WORKTREES.md`): a pristine
+   worktree is removed, one holding unsaved work is left on disk. No recovery
+   marker is written. This death is permanent — a later daemon restart's
+   `recover()` finds the sidecar, sees no marker, and leaves the session
+   `Dead` without attempting to resume it.
+2. **A cancelled turn fails to settle within `CANCEL_GRACE`.** Same
+   consequence as (1): the session is marked dead through the same path, no
+   marker, no future resumption.
+3. **Graceful daemon shutdown**, while the session was still `Running`.
+   `mark_session_dead_after_shutdown` marks the session dead **without**
+   applying the worktree exit rule — the tree is kept exactly as it is,
+   pristine or not, because there is nothing "natural" about this exit — and
+   writes the `.recover` marker. The sidecar on disk therefore says `Dead`,
+   but is eligible for resumption.
+
+Recovery, on the next daemon's `recover()`: for every `Structured` sidecar
+not already adopted, the marker is consumed. When one was present and the
+sidecar carries a stored `acp_session_id`, the daemon spawns a fresh adapter
+with `SpawnConfig::load_session(acp_session_id)`, replays the
+entire durable event log into a new `Projection` (rebuilding the transcript
+and reduced state exactly as they were, with any restored `Approval` row
+landing as history — never as a re-armed pending approval, since its nonce
+never reached disk), and only then reopens the log for further appends. What
+the adapter streams back while its own `session/load` is in flight is
+discarded rather than appended, so the replayed history is not duplicated
+(see [The ACP handshake](#the-acp-handshake)). Success flips the session back
+to `Running`/`Idle`; failure (no stored `acp_session_id`, or the handshake
+itself failing) leaves it `Dead` with the failure reason as
+`activity_detail` — the same "tell the operator what to fix" pattern as a
+missing adapter binary.
+
+Pending approvals and their nonces never survive any of this. They live only
+in the in-memory `pending_approvals` map and the live `ReducedState`, both
+gone the instant the daemon that held them exits. Whatever ACP permission
+request was mid-flight when the old daemon died was already answered
+`Cancelled` on that daemon's own shutdown path, so a resumed session always
+starts with no pending approval.
+
+See `docs/RESTART.md` for what a *client* observes across a daemon restart,
+now that structured sessions exist alongside terminal ones.

docs/WORKTREES.md

@@ -35,10 +35,18 @@ The branch name is used verbatim as a relative path, so `feature/login` becomes
 back to a short hash of the branch.
 
 If that path exists, the daemon appends `-2`, then `-3`, and so on until it finds
-a free one. The suffix names the **directory only**. The branch is whatever was
-requested; a second worktree of the same branch is not what happens here, because
-git refuses to check the same branch out twice and the branch picker already
-marks branches that are checked out elsewhere.
+a free one.
+
+For a *new* branch (`create_branch: true`), the suffix goes on the branch name
+itself, and the directory follows since it is derived from the branch — a
+random handle can otherwise reuse the name of a branch some earlier, already
+removed worktree left behind, and `git worktree add -b` refuses outright even
+though the directory is free.
+
+For an *existing* branch (`create_branch: false`) the name must stay exact, so
+only the directory is suffixed — a second worktree of the same branch is not
+what happens here, because git refuses to check the same branch out twice and
+the branch picker already marks branches that are checked out elsewhere.
 
 ### The `worktree_root` override
 

web/src/api.ts

@@ -11,6 +11,8 @@ import type {
   Projects,
   RecentDirs,
   Session,
+  StructuredApprovalDecision,
+  StructuredPromptRequest,
   Uuid,
 } from "./types.js";
 
@@ -152,4 +154,44 @@ export async function fetchBranches(path: string): Promise<Branches> {
   return jsonOrError(await fetch(url, { credentials: "same-origin" }));
 }
 
-export { eventsWsUrl } from "./routes.js";
+/** Send a prompt to a structured session's ACP turn (#138). `409
+ * turn_in_flight` when one is already active — the caller reflects that from
+ * `ReducedState.turn` instead of racing this call. */
+export async function sendStructuredPrompt(id: Uuid, prompt: string): Promise<void> {
+  await jsonOrError(
+    await fetch(routes.structuredPrompt(id), {
+      method: "POST",
+      credentials: "same-origin",
+      headers: { "content-type": "application/json" },
+      body: JSON.stringify({ prompt } satisfies StructuredPromptRequest),
+    }),
+  );
+}
+
+/** Cancel a structured session's active ACP turn (#138). */
+export async function cancelStructuredTurn(id: Uuid): Promise<void> {
+  await jsonOrError(
+    await fetch(routes.structuredCancel(id), { method: "POST", credentials: "same-origin" }),
+  );
+}
+
+/** Answer a pending ACP permission request (#139). Always resolves once the
+ * session itself is a live structured session — a nonce that is unknown or
+ * already consumed still answers `204` (docs/STRUCTURED-VIEW.md), so two
+ * clients racing the same approval never see this reject. */
+export async function resolveStructuredApproval(
+  id: Uuid,
+  nonce: string,
+  decision: StructuredApprovalDecision,
+): Promise<void> {
+  await jsonOrError(
+    await fetch(routes.structuredApproval(id, nonce), {
+      method: "POST",
+      credentials: "same-origin",
+      headers: { "content-type": "application/json" },
+      body: JSON.stringify(decision),
+    }),
+  );
+}
+
+export { eventsWsUrl, structuredWsUrl } from "./routes.js";

web/src/attach.ts

@@ -4,15 +4,16 @@ import { Terminal } from "@xterm/xterm";
 import "@xterm/xterm/css/xterm.css";
 
 import { attachWsUrl } from "./routes.js";
-import { FOCUS_SIDEBAR_EVENT } from "./catalog.js";
-import { escapeHtml } from "./html.js";
 import { INITIAL_RECONNECT_MS, MAX_RECONNECT_MS } from "./reconnect.js";
 import { applyModsToChar, cursorSeq, tildeSeq } from "./keys.js";
 import { requestToggleDrawer } from "./drawer.js";
-import { splitCommand, toolIconSvg } from "./toolIcon.js";
+import { paneTitleAttr, paneTitleHtml, type AttachInfo } from "./paneTitle.js";
+import type { PaneConnection } from "./pane.js";
 import type { ClientControl, Uuid } from "./types.js";
 import { WebglPolicy } from "./webglRenderer.js";
 
+export type { AttachInfo } from "./paneTitle.js";
+
 /** One budget for the whole page — see webglRenderer.ts for why contexts are
  *  rationed rather than handed to every connection. */
 const webglPolicy = new WebglPolicy();
@@ -28,19 +29,7 @@ const webglPolicy = new WebglPolicy();
  * session ending) tears the socket down — so switching away and back is
  * instant, with scrollback already in place.
  */
-export interface AttachConnection {
-  readonly sessionId: Uuid;
-  /** The `.attach` element (header + terminal body) to mount into a pane. */
-  readonly el: HTMLElement;
-  /** Becomes the visible view: fit to the pane, focus, sync size. */
-  onMount(): void;
-  /** Parked into the cache: keep streaming, just stop driving focus/resize. */
-  onUnmount(): void;
-  /** Put the keyboard back into this terminal — what leaving the sidebar does. */
-  focusTerminal(): void;
-  /** Fully disconnect: close the WS, dispose the terminal, remove the element. */
-  dispose(): void;
-}
+export interface AttachConnection extends PaneConnection {}
 
 export interface AttachOptions {
   /** Invoked when the user clicks the view's explicit "disconnect" control. */
@@ -54,25 +43,6 @@ export interface AttachOptions {
   shouldReconnect?: (sessionId: Uuid, code: number) => boolean;
 }
 
-
-
-/** What the header shows about the session (name / command). Optional — falls
- * back to a short session id when the session isn't known yet. */
-export interface AttachInfo {
-  name: string;
-  command: string;
-}
-
-/** Header echoes the sidebar: the program becomes its tool icon when we have a
- * mark for it and stays as its bare name when we do not. Arguments are
- * dropped, as on the card. */
-function commandFragment(command: string): string {
-  const { tool, program } = splitCommand(command);
-  const icon = tool ? toolIconSvg(tool) : null;
-  const text = icon ? "" : program;
-  return `<span class="at-cmd">${icon ?? ""}${text ? escapeHtml(text) : ""}</span>`;
-}
-
 export function createAttachConnection(
   sessionId: Uuid,
   opts: AttachOptions = {},
@@ -82,15 +52,12 @@ export function createAttachConnection(
   el.className = "attach";
   // Useful identity over a bare UUID: name · command. The full id stays in the
   // tooltip for when you really need it.
-  const titleHtml = info
-    ? `<span class="at-name">${escapeHtml(info.name)}</span>` +
-      (info.command && info.command !== info.name ? commandFragment(info.command) : "")
-    : `session <span class="sid">${escapeHtml(sessionId.slice(0, 8))}</span>`;
-  const titleAttr = info ? `${info.name} · ${info.command}  (${sessionId})` : sessionId;
+  const titleHtml = paneTitleHtml(sessionId, info);
+  const titleAttr = paneTitleAttr(sessionId, info);
   el.innerHTML = `
     <header class="attach-header">
       <button type="button" class="btn btn-ghost btn-icon sessions-btn" aria-label="Show sessions" title="Show sessions">☰</button>
-      <span class="attach-title" title="${escapeHtml(titleAttr)}">${titleHtml}</span>
+      <span class="attach-title" title="${titleAttr}">${titleHtml}</span>
       <span class="attach-state" data-state="connecting">connecting…</span>
       <button class="btn btn-ghost btn-icon disconnect" type="button" aria-label="Disconnect" title="Disconnect this session">⏻</button>
     </header>
@@ -207,15 +174,6 @@ export function createAttachConnection(
     }
   }
 
-  // Plain Escape hands the keyboard back to the session list instead of the
-  // shell/app. `false` tells xterm to skip its own handling of this event.
-  term.attachCustomKeyEventHandler((e) => {
-    if (e.type !== "keydown" || e.key !== "Escape") return true;
-    if (e.ctrlKey || e.altKey || e.metaKey || e.shiftKey) return true;
-    document.dispatchEvent(new CustomEvent(FOCUS_SIDEBAR_EVENT));
-    return false;
-  });
-
   // Touch scrolling: xterm's built-in touch handling is jittery (drags crawl a
   // line at a time and stall), so map finger drags ourselves. Two routes:
   //   • normal buffer  → term.scrollLines walks the scrollback.
@@ -309,6 +267,10 @@ export function createAttachConnection(
   }
 
   let mounted = false;
+  // A previewed pane is visible but must not steal the keyboard from the
+  // sidebar, so mounting can opt out of the focus grab (and out of the one
+  // the socket does when it finishes connecting).
+  let focusOnMount = true;
   // We compute the fit ourselves instead of FitAddon.fit(): the addon subtracts
   // a scrollbar width that xterm reports as `offsetWidth - scrollArea || 15`,
   // so with the scrollbar hidden it falls back to a phantom 15px and the grid
@@ -387,7 +349,7 @@ export function createAttachConnection(
       reconnectMs = INITIAL_RECONNECT_MS;
       setState("connected", "open");
       sendControl({ type: "Resize", cols: term.cols, rows: term.rows });
-      if (mounted) term.focus();
+      if (mounted && focusOnMount) term.focus();
     };
 
     ws.onmessage = (ev) => {
@@ -452,6 +414,12 @@ export function createAttachConnection(
   const resizeDisp = term.onResize(({ cols, rows }) => {
     sendControl({ type: "Resize", cols, rows });
   });
+  // xterm has no built-in copy-on-select; mirror the selection to the
+  // clipboard ourselves (best-effort — insecure contexts lack the API).
+  const selectionDisp = term.onSelectionChange(() => {
+    const text = term.getSelection();
+    if (text) void navigator.clipboard?.writeText(text).catch(() => {});
+  });
 
   window.addEventListener("resize", onResize);
   const visual = window.visualViewport ?? null;
@@ -472,14 +440,15 @@ export function createAttachConnection(
   return {
     sessionId,
     el,
-    onMount() {
+    onMount(mountOpts?: { focus?: boolean }) {
       mounted = true;
+      focusOnMount = mountOpts?.focus !== false;
       acquireWebgl();
       // Defer a tick so the element has its content-pane dimensions before fit.
       requestAnimationFrame(() => {
         tryFit();
         sendControl({ type: "Resize", cols: term.cols, rows: term.rows });
-        if (ws.readyState === WebSocket.OPEN) term.focus();
+        if (focusOnMount && ws.readyState === WebSocket.OPEN) term.focus();
       });
     },
     onUnmount() {
@@ -491,6 +460,9 @@ export function createAttachConnection(
     focusTerminal() {
       term.focus();
     },
+    // The closure above: the same bytes-out path keystrokes and the mobile key
+    // bar already take.
+    sendInput,
     dispose() {
       if (disposed) return;
       disposed = true;
@@ -503,6 +475,7 @@ export function createAttachConnection(
       visual?.removeEventListener("resize", onResize);
       dataDisp.dispose();
       resizeDisp.dispose();
+      selectionDisp.dispose();
       releaseWebgl();
       try {
         ws.close();

web/src/barActions.test.ts

@@ -0,0 +1,139 @@
+// @vitest-environment happy-dom
+//
+// The sidebar's half of the command bar's action page (#151): the bar picks
+// kill or rename and raises the flow the card already has, so what the page
+// runs is what the ✕ button and the `r` key run.
+import { afterEach, beforeAll, describe, expect, it } from "vitest";
+
+import { KILL_SESSION_EVENT, RENAME_SESSION_EVENT, renderSidebar } from "./catalog.js";
+import type { CatalogListener, CatalogStore } from "./events.js";
+import type { Session } from "./types.js";
+
+beforeAll(() => {
+  Object.defineProperty(window, "localStorage", {
+    value: { getItem: () => null, setItem: () => {} },
+  });
+});
+
+let mounted: { el: HTMLElement; dispose: () => void } | null = null;
+
+afterEach(() => {
+  document.querySelector(".kill-dialog")?.remove();
+  mounted?.dispose();
+  mounted = null;
+  document.body.replaceChildren();
+});
+
+function session(overrides: Partial<Session> = {}): Session {
+  return {
+    id: "aaaaaaaa-0000-0000-0000-0000000000ff",
+    cwd: "/home/naps/tea/maestro",
+    command: "claude",
+    env: {},
+    metadata: { name: "amber-falcon" },
+    status: "Running",
+    created_at: "2026-08-24T10:00:00Z",
+    ...overrides,
+  };
+}
+
+function storeWith(sessions: Session[]): CatalogStore {
+  const state = { sessions: new Map(sessions.map((s) => [s.id, s])) };
+  return {
+    snapshot: () => state,
+    subscribe: (fn: CatalogListener) => {
+      fn(state);
+      return () => {};
+    },
+  } as unknown as CatalogStore;
+}
+
+function mount(s: Session): HTMLElement {
+  const handle = renderSidebar(storeWith([s]));
+  mounted = handle;
+  document.body.appendChild(handle.el);
+  return handle.el;
+}
+
+function raise(name: string, s: Session): void {
+  document.dispatchEvent(new CustomEvent(name, { detail: s }));
+}
+
+/** Let the kill chain's awaits (fetch, its json body) settle. */
+async function flush(): Promise<void> {
+  for (let i = 0; i < 8; i++) await Promise.resolve();
+}
+
+describe("kill from the action page", () => {
+  it("goes through the same confirmation the sidebar raises (#160)", async () => {
+    const calls: string[] = [];
+    window.fetch = ((url: string, init?: RequestInit) => {
+      calls.push(`${init?.method ?? "GET"} ${url}`);
+      return Promise.resolve(new Response(null, { status: 204 }));
+    }) as typeof fetch;
+    const s = session();
+    mount(s);
+    raise(KILL_SESSION_EVENT, s);
+    await flush();
+    expect(document.querySelector(".kill-dialog")?.getAttribute("aria-label")).toBe(
+      "Kill amber-falcon",
+    );
+    expect(calls.filter((c) => c.startsWith("DELETE"))).toHaveLength(0);
+    document.querySelector<HTMLButtonElement>(".kill-dialog-kill")?.click();
+    await flush();
+    expect(calls).toContain(`DELETE /api/sessions/${s.id}`);
+    expect(document.querySelector(".kill-dialog")).toBeNull();
+  });
+
+  it("raises the existing confirm-and-blockers dialog on a guarded refusal", async () => {
+    window.fetch = ((url: string) => {
+      if (String(url).includes("force=true")) {
+        return Promise.resolve(new Response(null, { status: 204 }));
+      }
+      return Promise.resolve(
+        new Response(
+          JSON.stringify({
+            error: {
+              code: "kill_guarded",
+              message: "worktree has unsaved work",
+              unsaved_work: { untracked_files: 1 },
+            },
+          }),
+          { status: 409, headers: { "content-type": "application/json" } },
+        ),
+      );
+    }) as typeof fetch;
+    const s = session({ blocked_work: { untracked_files: 1 } });
+    mount(s);
+    raise(KILL_SESSION_EVENT, s);
+    await flush();
+    document.querySelector<HTMLButtonElement>(".kill-dialog-kill")?.click();
+    await flush();
+    const dialog = document.querySelector(".kill-dialog");
+    expect(dialog?.getAttribute("aria-label")).toBe("Kill amber-falcon");
+    expect(dialog?.textContent).toContain("1 untracked file");
+  });
+});
+
+describe("rename from the action page", () => {
+  it("expands the folder hiding the card, since the prompt lives in the card", () => {
+    window.fetch = (() => Promise.reject(new Error("offline"))) as typeof fetch;
+    const s = session();
+    const el = mount(s);
+    const folder = el.querySelector<HTMLElement>(".tree-folder-header");
+    folder?.click();
+    expect(el.querySelector(`[data-session-id="${s.id}"]`)).toBeNull();
+    raise(RENAME_SESSION_EVENT, s);
+    expect(el.querySelector<HTMLInputElement>(".leaf-rename")?.value).toBe("amber-falcon");
+  });
+
+  it("raises the card's own prompt, pre-filled with the session's name", () => {
+    window.fetch = (() => Promise.reject(new Error("offline"))) as typeof fetch;
+    const s = session();
+    const el = mount(s);
+    raise(RENAME_SESSION_EVENT, s);
+    const input = el.querySelector<HTMLInputElement>(".leaf-rename");
+    expect(input?.value).toBe("amber-falcon");
+    expect(input?.getAttribute("aria-label")).toBe("Rename amber-falcon");
+  });
+});

web/src/catalog.test.ts

@@ -98,7 +98,7 @@ describe("blocked-work indicator (#83)", () => {
     expect(rowFor(el, unprobed.id)?.querySelector(".leaf-blocked")).toBeNull();
   });
 
-  it("kills straight away, without a first confirmation", async () => {
+  it("confirms before an unguarded kill (#160)", async () => {
     const calls: string[] = [];
     window.fetch = ((url: string, init?: RequestInit) => {
       calls.push(`${init?.method ?? "GET"} ${url}`);
@@ -108,10 +108,45 @@ describe("blocked-work indicator (#83)", () => {
     const el = renderSidebar(storeWith([plain])).el;
     rowFor(el, plain.id)?.querySelector<HTMLButtonElement>(".leaf-kill")?.click();
     await flush();
+    const dialog = document.querySelector(".kill-dialog");
+    expect(dialog?.getAttribute("aria-label")).toBe("Kill claude");
+    expect(calls.filter((c) => c.startsWith("DELETE"))).toHaveLength(0);
+    dialog?.querySelector<HTMLButtonElement>(".kill-dialog-kill")?.click();
+    await flush();
     expect(calls).toContain(`DELETE /api/sessions/${plain.id}`);
     expect(document.querySelector(".kill-dialog")).toBeNull();
   });
 
+  it("kills nothing when the confirmation is cancelled (#160)", async () => {
+    const calls: string[] = [];
+    window.fetch = ((url: string, init?: RequestInit) => {
+      calls.push(`${init?.method ?? "GET"} ${url}`);
+      return Promise.resolve(new Response(null, { status: 204 }));
+    }) as typeof fetch;
+    const plain = session({ id: "aaaaaaaa-0000-0000-0000-000000000007" });
+    const el = renderSidebar(storeWith([plain])).el;
+    rowFor(el, plain.id)?.querySelector<HTMLButtonElement>(".leaf-kill")?.click();
+    await flush();
+    document.querySelector<HTMLButtonElement>(".kill-dialog-cancel")?.click();
+    await flush();
+    expect(document.querySelector(".kill-dialog")).toBeNull();
+    expect(calls.filter((c) => c.startsWith("DELETE"))).toHaveLength(0);
+  });
+
+  it("names the blockers in the confirmation, before the daemon refuses (#160)", async () => {
+    window.fetch = (() => Promise.reject(new Error("never called"))) as typeof fetch;
+    const blocked = session({
+      id: "aaaaaaaa-0000-0000-0000-000000000008",
+      blocked_work: { untracked_files: 1 },
+    });
+    const el = renderSidebar(storeWith([blocked])).el;
+    rowFor(el, blocked.id)?.querySelector<HTMLButtonElement>(".leaf-kill")?.click();
+    await flush();
+    const dialog = document.querySelector(".kill-dialog");
+    expect(dialog?.textContent).toContain("1 untracked file");
+    expect(dialog?.textContent).toContain("refused unless it is forced");
+  });
+
   it("offers the override when the daemon refuses a guarded kill", async () => {
     const calls: string[] = [];
     window.fetch = ((url: string, init?: RequestInit) => {
@@ -138,6 +173,8 @@ describe("blocked-work indicator (#83)", () => {
     const el = renderSidebar(storeWith([blocked])).el;
     rowFor(el, blocked.id)?.querySelector<HTMLButtonElement>(".leaf-kill")?.click();
     await flush();
+    document.querySelector<HTMLButtonElement>(".kill-dialog-kill")?.click();
+    await flush();
     const dialog = document.querySelector(".kill-dialog");
     expect(dialog?.textContent).toContain("1 untracked file");
     dialog?.querySelector<HTMLButtonElement>(".kill-dialog-force")?.click();
@@ -166,6 +203,8 @@ describe("blocked-work indicator (#83)", () => {
     const el = renderSidebar(storeWith([blocked])).el;
     rowFor(el, blocked.id)?.querySelector<HTMLButtonElement>(".leaf-kill")?.click();
     await flush();
+    document.querySelector<HTMLButtonElement>(".kill-dialog-kill")?.click();
+    await flush();
     document.querySelector<HTMLButtonElement>(".kill-dialog-cancel")?.click();
     expect(document.querySelector(".kill-dialog")).toBeNull();
     expect(calls.filter((c) => c.includes("force=true"))).toHaveLength(0);

web/src/catalog.ts

@@ -1,11 +1,13 @@
 import { escapeHtml } from "./html.js";
 import { ApiRequestError, getDaemonInfo, killSession, renameSession } from "./api.js";
-import { openForceKillDialog } from "./killDialog.js";
+import { openForceKillDialog, openKillConfirmDialog } from "./killDialog.js";
 import { openContextMenu } from "./contextMenu.js";
-import { isTypingTarget, toggleHelp } from "./help.js";
+import { toggleHelp } from "./help.js";
+import { CommandSet, defineCommands } from "./commands.js";
 import { CatalogStore } from "./events.js";
 import type { InTheWay, Session } from "./types.js";
 import {
+  abbreviateCwd,
   abbreviateFolderName,
   blockerStats,
   customSessionName,
@@ -15,6 +17,7 @@ import {
   sessionBlockers,
   isProvisionalName,
   sessionName,
+  sessionTreePath,
 } from "./types.js";
 import { splitCommand, toolIconSvg } from "./toolIcon.js";
 import {
@@ -36,19 +39,35 @@ export function requestOpenSpawn(): void {
   document.dispatchEvent(new CustomEvent(OPEN_SPAWN_EVENT));
 }
 
+/** Ask the shell to open the command bar with an empty query. Dispatched by
+ *  the sidebar's search field, which is the touch entry point to the bar
+ *  (#157, docs/COMMAND-BAR.md "Touch entry"): there is no `ctrl-k` on a phone.
+ *  Handled in main.ts, which owns the session snapshot the bar needs. */
+export const OPEN_COMMAND_BAR_EVENT = "catalog-open-command-bar";
+export function requestOpenCommandBar(): void {
+  document.dispatchEvent(new CustomEvent(OPEN_COMMAND_BAR_EVENT));
+}
+
 /** Ask the shell to hand the keyboard back to the focused pane's terminal —
  *  what Tab in the sidebar list does. Handled in main.ts, which owns the
  *  connection pool. */
 export const FOCUS_PANE_EVENT = "catalog-focus-pane";
 
-/** Ask the shell to hand the keyboard back to the session list — what Escape
- *  does when the pane's terminal is focused. Handled in main.ts. */
-export const FOCUS_SIDEBAR_EVENT = "catalog-focus-sidebar";
-
 /** Ask the shell to open the spawn modal seeded from an existing session
  *  ("Spawn similar"). Detail is the session being cloned. */
 export const SPAWN_SIMILAR_EVENT = "catalog-spawn-similar";
 
+/** Ask the sidebar to kill a session — the command bar's action page picking
+ *  `kill` (#151). Detail is the session. Handled here, so the kill goes
+ *  through the same confirm-and-blockers flow the card's ✕ does
+ *  (`docs/WORKTREES.md`); the bar never reimplements it. */
+export const KILL_SESSION_EVENT = "catalog-kill-session";
+
+/** Ask the sidebar to rename a session — the command bar's action page picking
+ *  `rename` (#151). Detail is the session. The prompt is the card's own inline
+ *  field, pre-filled with the session's name (`docs/SIDEBAR.md`). */
+export const RENAME_SESSION_EVENT = "catalog-rename-session";
+
 /** A session row was clicked (issue #133). The row's `href` drives normal
  *  hash navigation, but a split/drag can move focus without ever touching
  *  `location.hash` — so a click back onto a session whose hash still
@@ -164,6 +183,10 @@ function renderNode(node: TreeNode, depth: number): HTMLElement {
     return wrap;
   }
 
+  // The row outlives the snapshot it was built from: a refresh that changes
+  // nothing structural patches it in place rather than replacing it, so the
+  // handlers below have to read the current session, not the one captured here.
+  let cur = node.session;
   const s = node.session;
   const now = Date.now();
   const row = document.createElement("a");
@@ -197,54 +220,102 @@ function renderNode(node: TreeNode, depth: number): HTMLElement {
   similarBtn.addEventListener("click", (ev) => {
     ev.preventDefault();
     ev.stopPropagation();
-    document.dispatchEvent(new CustomEvent(SPAWN_SIMILAR_EVENT, { detail: s }));
+    document.dispatchEvent(new CustomEvent(SPAWN_SIMILAR_EVENT, { detail: cur }));
   });
   const killBtn = row.querySelector(".leaf-kill") as HTMLButtonElement;
   killBtn.addEventListener("click", (ev) => {
     ev.preventDefault();
     ev.stopPropagation();
-    void requestKill(s, name);
+    requestKill(cur, sessionName(cur));
   });
   row.addEventListener("click", () => {
-    document.dispatchEvent(new CustomEvent(SESSION_SELECT_EVENT, { detail: s.id }));
+    document.dispatchEvent(new CustomEvent(SESSION_SELECT_EVENT, { detail: cur.id }));
   });
   row.addEventListener("contextmenu", (ev) => {
     ev.preventDefault();
     ev.stopPropagation();
     openContextMenu(ev.clientX, ev.clientY, [
-      { label: "Rename…", onSelect: () => beginRename(row, s) },
+      { label: "Rename…", onSelect: () => beginRename(row, cur) },
       {
         label: "Spawn similar",
         onSelect: () =>
-          document.dispatchEvent(new CustomEvent(SPAWN_SIMILAR_EVENT, { detail: s })),
+          document.dispatchEvent(new CustomEvent(SPAWN_SIMILAR_EVENT, { detail: cur })),
+      },
+      {
+        label: "Kill session",
+        danger: true,
+        onSelect: () => requestKill(cur, sessionName(cur)),
       },
-      { label: "Kill session", danger: true, onSelect: () => void requestKill(s, name) },
     ]);
   });
+  leafPatches.set(row, (next) => {
+    cur = next;
+    const nextSlug = activityColorSlug(next.activity ?? "Idle");
+    const nextWord = STATE_WORDS[nextSlug] ?? STATE_WORDS.idle;
+    row.setAttribute(
+      "aria-label",
+      `${sessionName(next)}, ${next.status === "Running" ? "running" : "exited"}, ${nextWord}`,
+    );
+    const rail = row.querySelector(".activity-rail");
+    if (rail) rail.outerHTML = activityRailMarkup(nextSlug, nextWord);
+    const meta = row.querySelector(".card-line2");
+    if (meta) meta.outerHTML = metaLine(next, Date.now());
+  });
   return row;
 }
 
+/** Refresh a standing card from a newer snapshot of its session, keeping the
+ *  element (and so the pointer's `:hover`) exactly where it is. Registered by
+ *  `renderNode`; only the bits `treeSignature` leaves out are rewritten. */
+const leafPatches = new WeakMap<HTMLElement, (s: Session) => void>();
+
 /**
- * Kill on the first click (#81): the daemon is the one that decides whether a
- * session may go, and it refuses over a worktree holding unsaved work. Only
- * that refusal is worth a prompt, and it needs one `confirm()` cannot give —
- * a forced kill. Anything else surfaces as an alert.
+ * Everything about the tree that a patch cannot fix up.
+ *
+ * The daemon re-sends a session on every activity, foreground or cwd shift —
+ * a couple of times a minute per live session — and rebuilding the sidebar for
+ * each one drops `:hover` from the row under the pointer. Refreshes whose
+ * signature is unchanged are patched into the standing rows instead; anything
+ * that moves, renames, appears or dies changes the signature and rebuilds.
  */
-async function requestKill(s: Session, name: string): Promise<void> {
-  try {
-    await killSession(s.id);
-  } catch (e) {
-    if (e instanceof ApiRequestError && e.code === "kill_guarded") {
-      openForceKillDialog({
-        name,
-        blockers: e.unsavedWork ?? sessionBlockers(s),
-        reason: e.detail,
-        onForce: () => killSession(s.id, true),
-      });
-      return;
-    }
-    alert(`Failed to kill: ${(e as Error).message}`);
+function treeSignature(node: TreeNode): string {
+  if (node.kind === "folder") {
+    const head = `F:${node.name}:${node.path}:${collapsed.has(node.path)}`;
+    if (node.name && collapsed.has(node.path)) return head;
+    return `${head}(${node.children.map(treeSignature).join(",")})`;
   }
+  const s = node.session;
+  return `L:${s.id}:${sessionName(s)}:${s.status}:${isProvisionalName(s)}`;
+}
+
+/**
+ * Kill behind a confirmation (#160): a kill is destructive and unattended
+ * agents live in these sessions, so the web asks first, the way the TUI always
+ * has. The daemon decides the rest — it refuses a kill over a worktree holding
+ * unsaved work, and that refusal needs a prompt the confirmation cannot give,
+ * a forced kill. Anything else surfaces in the dialog that asked.
+ */
+function requestKill(s: Session, name: string): void {
+  openKillConfirmDialog({
+    name,
+    blockers: sessionBlockers(s),
+    onKill: async () => {
+      try {
+        await killSession(s.id);
+      } catch (e) {
+        if (e instanceof ApiRequestError && e.code === "kill_guarded") {
+          openForceKillDialog({
+            name,
+            blockers: e.unsavedWork ?? sessionBlockers(s),
+            reason: e.detail,
+            onForce: () => killSession(s.id, true),
+          });
+          return;
+        }
+        throw e;
+      }
+    },
+  });
 }
 
 /**
@@ -302,16 +373,12 @@ function beginRename(row: HTMLElement, s: Session): void {
   input.select();
 }
 
-function renderEmpty(filtering: boolean, onSpawn: () => void): HTMLElement {
+// The tree has one empty state: no sessions at all. The old "No matches" one
+// belonged to the inline substring filter, which the command bar replaced
+// (#157) — the bar's own no-results state took over with it.
+function renderEmpty(onSpawn: () => void): HTMLElement {
   const el = document.createElement("div");
   el.className = "empty";
-  if (filtering) {
-    el.innerHTML = `
-      <div class="empty-glyph" aria-hidden="true">⌕</div>
-      <div class="empty-title">No matches</div>
-      <p class="empty-hint">No sessions match your search. Clear it to see everything.</p>`;
-    return el;
-  }
   el.innerHTML = `
     <div class="empty-glyph" aria-hidden="true">+</div>
     <div class="empty-title">No sessions yet</div>
@@ -342,6 +409,9 @@ export interface SidebarHandle {
   setActive(id: string | null): void;
   /** Apply the full open/focused highlight state. */
   setHighlights(h: SidebarHighlights): void;
+  /** Mark the row the content pane is previewing (docs/PREVIEW.md), or clear it
+   *  with `null`. A preview is a view, not state, so this only paints. */
+  setPreview(sessionId: string | null): void;
   /** Hand the keyboard to the session list, highlighting a row to walk from. */
   focusList(): void;
   /** Whether the session list currently holds DOM focus. */
@@ -364,6 +434,11 @@ export interface SidebarOptions {
   /** Daemon link behind the footer's status dot. Omitted in tests and in the
    *  design kit, which render the sidebar without a daemon. */
   link?: DaemonLink;
+  /** The highlight moved onto a session, or off every session (`null`): the
+   *  shell shows it in the content pane without opening it (docs/PREVIEW.md).
+   *  `source` is there so a mouse sweep can be debounced differently from a
+   *  keyboard step. */
+  onPreview?: (sessionId: string | null) => void;
 }
 
 export function renderSidebar(store: CatalogStore, opts: SidebarOptions = {}): SidebarHandle {
@@ -374,12 +449,16 @@ export function renderSidebar(store: CatalogStore, opts: SidebarOptions = {}): S
   // renders with absolute paths until it lands.
   let homeDir: string | undefined;
 
+  // The field never holds a query: it is the touch entry point to the command
+  // bar (#157), so it is `readonly` — a tap opens the bar instead of raising an
+  // on-screen keyboard over a field nothing is typed into.
   const searchHeader = document.createElement("header");
   searchHeader.className = "sidebar-search";
   searchHeader.innerHTML = `
     <input
       type="search"
       class="search"
+      readonly
       placeholder="Search sessions…"
       aria-label="Search sessions"
       autocomplete="off"
@@ -488,14 +567,30 @@ export function renderSidebar(store: CatalogStore, opts: SidebarOptions = {}): S
   handle.addEventListener("pointerup", endDrag);
   handle.addEventListener("pointercancel", endDrag);
 
+  // Touch entry (#157): the field is a button that looks like a field. It
+  // never holds a query — focusing or tapping it hands the keyboard straight
+  // to the bar's own input, which is also why it blurs first: leaving the
+  // focus here would make the bar impossible to close without reopening it.
   const search = searchHeader.querySelector(".search") as HTMLInputElement;
-  let filter = "";
-  search.addEventListener("input", () => {
-    filter = search.value;
-    refresh();
+  const openBar = () => {
+    search.value = "";
+    search.blur();
+    requestOpenCommandBar();
+  };
+  search.addEventListener("focus", openBar);
+  // A tap can land without a focus event (iOS Safari on a blurred field), so
+  // the pointer path opens the bar too; the blur above keeps the two from
+  // stacking two overlays.
+  search.addEventListener("pointerdown", (e) => {
+    e.preventDefault();
+    openBar();
   });
 
   let highlights: SidebarHighlights = { open: new Set(), focused: null };
+  // The previewed row is painted alongside the open/focused tiers so a
+  // re-render can't drop it, but it is never part of `highlights`: a preview
+  // is a view, and nothing about it is durable (docs/PREVIEW.md).
+  let previewing: string | null = null;
   const applyHighlights = () => {
     for (const n of treeHost.querySelectorAll<HTMLElement>(".tree-leaf")) {
       const id = n.dataset.sessionId;
@@ -504,6 +599,7 @@ export function renderSidebar(store: CatalogStore, opts: SidebarOptions = {}): S
       const open = highlights.open.has(id);
       n.classList.toggle("is-active", focused);
       n.classList.toggle("is-open", open && !focused);
+      n.classList.toggle("is-previewing", previewing === id);
     }
   };
 
@@ -528,6 +624,9 @@ export function renderSidebar(store: CatalogStore, opts: SidebarOptions = {}): S
     for (const r of rows) r.classList.toggle("is-highlighted", r.dataset.navKey === navKey);
   };
 
+  const sessionOf = (key: string | null): string | null =>
+    key?.startsWith("session:") ? key.slice("session:".length) : null;
+
   const moveNav = (delta: number) => {
     const rows = navRows();
     if (rows.length === 0) return;
@@ -539,6 +638,7 @@ export function renderSidebar(store: CatalogStore, opts: SidebarOptions = {}): S
     navKey = next.dataset.navKey ?? null;
     applyNav();
     next.scrollIntoView({ block: "nearest" });
+    opts.onPreview?.(sessionOf(navKey));
   };
 
   /** Enter: open the highlighted session, or expand the highlighted folder. */
@@ -563,32 +663,96 @@ export function renderSidebar(store: CatalogStore, opts: SidebarOptions = {}): S
     applyNav();
   };
 
+  // Hover previews the row under the pointer (docs/PREVIEW.md). Touch is left
+  // out: there is no hover there, and a tap already opens the session.
+  let hovered: string | null = null;
+  const setHovered = (id: string | null) => {
+    if (hovered === id) return;
+    hovered = id;
+    opts.onPreview?.(id);
+  };
+  treeHost.addEventListener("pointerover", (e) => {
+    if (e.pointerType === "touch") return;
+    const row = (e.target as HTMLElement | null)?.closest<HTMLElement>(".tree-leaf");
+    setHovered(row?.dataset.sessionId ?? null);
+  });
+  treeHost.addEventListener("pointerleave", (e) => {
+    if (e.pointerType === "touch") return;
+    setHovered(null);
+  });
+
   // Focusable as a unit: the walk moves a highlight, not DOM focus, so the
   // keyboard stays here while j/k runs.
   treeHost.tabIndex = -1;
-  treeHost.addEventListener("keydown", (e) => {
-    if (e.ctrlKey || e.altKey || e.metaKey) return;
-    // The inline rename field lives inside a row and owns its own keys.
-    if (isTypingTarget(e.target)) return;
-    if (e.key === "j" || e.key === "ArrowDown") moveNav(1);
-    else if (e.key === "k" || e.key === "ArrowUp") moveNav(-1);
-    else if (e.key === "Enter") activateNav();
-    else if (e.key === "Tab") document.dispatchEvent(new CustomEvent(FOCUS_PANE_EVENT));
-    else return;
-    e.preventDefault();
-  });
+  // The keyboard walk's preview belongs to the list having the keyboard: once
+  // it doesn't, the content pane goes back to what the operator actually opened.
+  treeHost.addEventListener("blur", () => opts.onPreview?.(null));
+
+  /** The session behind the highlighted row, if the highlight is on a card. */
+  const highlightedSession = (): { row: HTMLElement; session: Session } | undefined => {
+    const row = rowFor(navKey);
+    const id = row?.dataset.sessionId;
+    if (!row || !id) return undefined;
+    const session = store.snapshot().sessions.get(id);
+    return session ? { row, session } : undefined;
+  };
+
+  /** `c`: collapse or expand the highlighted folder, the TUI's
+   *  `ToggleSidebarGroup`. Clicking the header is what toggles it; on a card
+   *  the key does nothing rather than toggling some other folder. */
+  const toggleHighlightedFolder = () => {
+    const row = rowFor(navKey);
+    if (!row || !row.classList.contains("tree-folder-header")) return;
+    row.click();
+    applyNav();
+  };
+
+  // The session list's half of the command registry (#148). One set per
+  // sidebar, so a second sidebar (tests, hot reload) drives its own rows; the
+  // labels and chords still come from the one registry.
+  const listKeys = new CommandSet(
+    defineCommands({
+      "list.next": () => moveNav(1),
+      "list.prev": () => moveNav(-1),
+      "list.activate": () => activateNav(),
+      "list.toggleFolder": () => toggleHighlightedFolder(),
+      "list.rename": () => {
+        const hit = highlightedSession();
+        if (hit) beginRename(hit.row, hit.session);
+      },
+      "list.kill": () => {
+        const hit = highlightedSession();
+        if (hit) requestKill(hit.session, sessionName(hit.session));
+      },
+      "list.focusPane": () => document.dispatchEvent(new CustomEvent(FOCUS_PANE_EVENT)),
+    }),
+  );
+
+  // The inline rename field lives inside a row and owns its own keys; the set's
+  // plain-key rule keeps this walk out of it.
+  treeHost.addEventListener("keydown", (e) => listKeys.handle(e));
+
+  /** Signature of what is currently on screen — see `treeSignature`. */
+  let renderedSignature: string | null = null;
 
   const refresh = () => {
     // Rebuilding the tree now would blow away the field being typed into.
     if (renamingId !== null) return;
     const state = store.snapshot();
     const sessions = [...state.sessions.values()];
-    const tree = buildTree(sessions, homeDir, filter);
+    const tree = buildTree(sessions, homeDir);
+    const signature = sessions.length === 0 ? "EMPTY" : treeSignature(tree);
+    if (signature === renderedSignature) {
+      for (const row of treeHost.querySelectorAll<HTMLElement>(".tree-leaf")) {
+        const s = row.dataset.sessionId ? state.sessions.get(row.dataset.sessionId) : undefined;
+        if (s) leafPatches.get(row)?.(s);
+      }
+      return;
+    }
+    renderedSignature = signature;
     treeHost.replaceChildren();
     if (sessions.length === 0) {
-      treeHost.appendChild(
-        renderEmpty(filter.trim().length > 0, () => requestOpenSpawn()),
-      );
+      treeHost.appendChild(renderEmpty(() => requestOpenSpawn()));
       return;
     }
     if (tree.kind === "folder") {
@@ -607,9 +771,49 @@ export function renderSidebar(store: CatalogStore, opts: SidebarOptions = {}): S
       /* absolute paths are a fine fallback */
     });
 
-  const rerenderHandler = () => refresh();
+  // Dispatched when something outside the store changed what the tree should
+  // look like — a folder collapsed, a rename ended — none of which the store
+  // snapshot can show, so the signature check has to be bypassed.
+  const rerenderHandler = () => {
+    renderedSignature = null;
+    refresh();
+  };
   document.addEventListener("catalog-rerender", rerenderHandler);
 
+  // The command bar's action page (#151) picks an action and hands it here:
+  // both flows are the ones the card already has, reached by session rather
+  // than by row.
+  const killHandler = (ev: Event) => {
+    const s = (ev as CustomEvent<Session>).detail;
+    requestKill(s, sessionName(s));
+  };
+  const renameHandler = (ev: Event) => {
+    const s = (ev as CustomEvent<Session>).detail;
+    const row = rowForSession(s);
+    if (row) beginRename(row, s);
+  };
+  document.addEventListener(KILL_SESSION_EVENT, killHandler);
+  document.addEventListener(RENAME_SESSION_EVENT, renameHandler);
+
+  /** The card a session is rendered as, expanding whatever folder hides it
+   *  first: the rename prompt lives inside the card, so a collapsed folder
+   *  would otherwise swallow the request. */
+  function rowForSession(s: Session): HTMLElement | null {
+    const find = () => treeHost.querySelector<HTMLElement>(`.tree-leaf[data-session-id="${s.id}"]`);
+    const found = find();
+    if (found) return found;
+    // Folder paths are the abbreviated directory's segments joined back up
+    // (see buildTree), so the session's own path is normalised the same way
+    // before it is compared against them.
+    const cwd = sessionTreePath(s);
+    const path = (cwd ? abbreviateCwd(cwd, homeDir) : "").split("/").filter(Boolean).join("/");
+    for (const folder of [...collapsed]) {
+      if (path === folder || path.startsWith(`${folder}/`)) collapsed.delete(folder);
+    }
+    rerenderHandler();
+    return find();
+  }
+
   // "Spawn similar" (#28) is dispatched here and handled in main.ts, where the
   // multi-view controller can seed the spawn modal with the session's dir/command.
 
@@ -635,6 +839,10 @@ export function renderSidebar(store: CatalogStore, opts: SidebarOptions = {}): S
       highlights = h;
       applyHighlights();
     },
+    setPreview(sessionId: string | null) {
+      previewing = sessionId;
+      applyHighlights();
+    },
     focusList() {
       // Start from the session on screen — that is where the user's attention
       // already is — falling back to the standing highlight, then the top row.
@@ -655,6 +863,8 @@ export function renderSidebar(store: CatalogStore, opts: SidebarOptions = {}): S
       // refusing to refresh.
       renamingId = null;
       document.removeEventListener("catalog-rerender", rerenderHandler);
+      document.removeEventListener(KILL_SESSION_EVENT, killHandler);
+      document.removeEventListener(RENAME_SESSION_EVENT, renameHandler);
       unsubscribe();
     },
   };

web/src/catalogPatch.test.ts

@@ -0,0 +1,105 @@
+// @vitest-environment happy-dom
+import { beforeAll, describe, expect, it } from "vitest";
+
+import { renderSidebar } from "./catalog.js";
+import type { CatalogListener, CatalogStore } from "./events.js";
+import type { Session } from "./types.js";
+
+beforeAll(() => {
+  Object.defineProperty(window, "localStorage", {
+    value: { getItem: () => null, setItem: () => {} },
+  });
+  window.fetch = () => Promise.reject(new Error("offline"));
+});
+
+const ID = "11111111-2222-3333-4444-555555555555";
+
+function session(overrides: Partial<Session> = {}): Session {
+  return {
+    id: ID,
+    cwd: "/home/naps/tea/maestro",
+    command: "claude",
+    env: {},
+    metadata: {},
+    status: "Running",
+    created_at: "2026-08-24T10:00:00Z",
+    ...overrides,
+  };
+}
+
+/** A store whose updates actually reach subscribers, unlike the one-shot
+ *  harness in catalog.test.ts. */
+function liveStore(initial: Session[]) {
+  const state = { sessions: new Map(initial.map((s) => [s.id, s])) };
+  const listeners = new Set<CatalogListener>();
+  const store = {
+    snapshot: () => state,
+    subscribe: (fn: CatalogListener) => {
+      listeners.add(fn);
+      fn(state);
+      return () => listeners.delete(fn);
+    },
+  } as unknown as CatalogStore;
+  const push = (sessions: Session[]) => {
+    state.sessions = new Map(sessions.map((s) => [s.id, s]));
+    for (const fn of listeners) fn(state);
+  };
+  return { store, push };
+}
+
+const rowOf = (el: HTMLElement) => el.querySelector<HTMLElement>(".tree-leaf")!;
+
+describe("sidebar refresh keeps rows in place (docs/SIDEBAR.md)", () => {
+  it("patches an activity change into the standing row instead of rebuilding it", () => {
+    const { store, push } = liveStore([session({ activity: "Idle" })]);
+    const { el } = renderSidebar(store, {});
+    const before = rowOf(el);
+
+    push([session({ activity: "AwaitingInput" })]);
+
+    // Same element: a rebuild under the pointer would drop `:hover` and restart
+    // the row's transitions, which is the flicker this avoids.
+    expect(rowOf(el)).toBe(before);
+    // …and the card still tells the truth about the session.
+    expect(before.querySelector(".activity-rail")?.getAttribute("data-activity")).toBe(
+      "awaiting-input",
+    );
+    expect(before.querySelector(".card-line2")?.getAttribute("data-activity")).toBe(
+      "awaiting-input",
+    );
+    expect(before.getAttribute("aria-label")).toContain("Awaiting input");
+  });
+
+  it("rebuilds when the row set changes", () => {
+    const { store, push } = liveStore([session()]);
+    const { el } = renderSidebar(store, {});
+    const before = rowOf(el);
+
+    push([session(), session({ id: "99999999-2222-3333-4444-555555555555", command: "bash" })]);
+
+    expect(el.querySelectorAll(".tree-leaf")).toHaveLength(2);
+    expect(rowOf(el)).not.toBe(before);
+  });
+
+  it("rebuilds when a session dies", () => {
+    const { store, push } = liveStore([session()]);
+    const { el } = renderSidebar(store, {});
+    const before = rowOf(el);
+
+    push([session({ status: "Dead" })]);
+
+    expect(rowOf(el)).not.toBe(before);
+    expect(rowOf(el).dataset.status).toBe("dead");
+  });
+
+  it("rebuilds when a session is renamed", () => {
+    const { store, push } = liveStore([session()]);
+    const { el } = renderSidebar(store, {});
+    const before = rowOf(el);
+
+    push([session({ metadata: { name: "harmony" } })]);
+
+    expect(rowOf(el)).not.toBe(before);
+    expect(rowOf(el).querySelector(".leaf-name")?.textContent).toBe("harmony");
+  });
+});

web/src/commandBar.test.ts

@@ -0,0 +1,723 @@
+// @vitest-environment happy-dom
+import { afterEach, describe, expect, it, vi } from "vitest";
+
+import {
+  KILL_SESSION_EVENT,
+  RENAME_SESSION_EVENT,
+  SESSION_SELECT_EVENT,
+  SPAWN_SIMILAR_EVENT,
+} from "./catalog.js";
+import {
+  barGroups,
+  barRows,
+  closeCommandBar,
+  commandBarCandidates,
+  dedupeCommands,
+  directoryBarCandidates,
+  directoryCandidate,
+  isCommandBarOpen,
+  openCommandBar,
+  orderSessionsForBar,
+  parseBarQuery,
+  sessionBarCandidates,
+  sessionActionCandidates,
+  sessionCandidate,
+  SPAWN_DIRECTORY_EVENT,
+} from "./commandBar.js";
+import { COMMAND_SPECS, type Command } from "./commands.js";
+import type { Session } from "./types.js";
+
+function session(id: string, over: Partial<Session> = {}): Session {
+  return {
+    id,
+    cwd: "/home/me/dev/api",
+    command: "bash",
+    env: {},
+    metadata: { name: id },
+    status: "Running",
+    created_at: "2026-01-01T00:00:00Z",
+    ...over,
+  };
+}
+
+afterEach(() => {
+  closeCommandBar();
+  document.body.replaceChildren();
+});
+
+function press(key: string, init: KeyboardEventInit = {}): void {
+  const input = document.querySelector(".cmdbar-input") as HTMLInputElement;
+  input.dispatchEvent(new KeyboardEvent("keydown", { key, bubbles: true, ...init }));
+}
+
+function type(value: string): void {
+  const input = document.querySelector(".cmdbar-input") as HTMLInputElement;
+  input.value = value;
+  input.dispatchEvent(new Event("input", { bubbles: true }));
+}
+
+function rowNames(): string[] {
+  return [...document.querySelectorAll(".cmdbar-row-name")].map((r) => r.textContent ?? "");
+}
+
+function activeName(): string | undefined {
+  return document.querySelector(".cmdbar-row.is-active .cmdbar-row-name")?.textContent ?? undefined;
+}
+
+describe("empty-query ordering", () => {
+  it("sorts most recently focused first", () => {
+    const older = session("older", { last_focused_at: "2026-01-01T10:00:00Z" });
+    const newer = session("newer", { last_focused_at: "2026-01-01T11:00:00Z" });
+    expect(orderSessionsForBar([older, newer]).map((s) => s.id)).toEqual(["newer", "older"]);
+  });
+
+  it("sorts a never-focused session after every focused one, newest created first", () => {
+    const focused = session("focused", {
+      last_focused_at: "2020-01-01T00:00:00Z",
+      created_at: "2020-01-01T00:00:00Z",
+    });
+    const oldFresh = session("old-fresh", { created_at: "2026-01-01T00:00:00Z" });
+    const newFresh = session("new-fresh", { created_at: "2026-06-01T00:00:00Z" });
+    expect(orderSessionsForBar([oldFresh, newFresh, focused]).map((s) => s.id)).toEqual([
+      "focused",
+      "new-fresh",
+      "old-fresh",
+    ]);
+  });
+
+  it("sorts dead sessions after live ones regardless of recency", () => {
+    const deadRecent = session("dead", {
+      status: "Dead",
+      last_focused_at: "2026-06-01T00:00:00Z",
+    });
+    const liveStale = session("live", { last_focused_at: "2020-01-01T00:00:00Z" });
+    const liveNever = session("never");
+    expect(orderSessionsForBar([deadRecent, liveNever, liveStale]).map((s) => s.id)).toEqual([
+      "live",
+      "never",
+      "dead",
+    ]);
+  });
+
+  it("treats a null last_focused_at as never focused", () => {
+    const nulled = session("nulled", { last_focused_at: null });
+    const stamped = session("stamped", { last_focused_at: "2020-01-01T00:00:00Z" });
+    expect(orderSessionsForBar([nulled, stamped]).map((s) => s.id)).toEqual(["stamped", "nulled"]);
+  });
+});
+
+describe("session candidates", () => {
+  it("carries the candidate table's fields, with the directory abbreviated", () => {
+    const s = session("api", {
+      metadata: { name: "api" },
+      command: "claude --resume",
+      current_cwd: "/home/me/dev/api",
+    });
+    expect(sessionCandidate(s, "/home/me")).toEqual({
+      kind: "session",
+      session: s,
+      fields: {
+        name: "api",
+        directory: "~/dev/api",
+        command: "claude --resume",
+        tool: "claude",
+      },
+    });
+  });
+
+  it("leaves the tool out when the program has no mark, and groups a worktree by its repo", () => {
+    const s = session("edit", {
+      metadata: {},
+      command: "hx src/",
+      worktree: { path: "/home/me/dev/api/wt/x", base_repo: "/home/me/dev/api" },
+    });
+    const candidate = sessionCandidate(s, "/home/me");
+    expect(candidate.fields.tool).toBeUndefined();
+    expect(candidate.fields.directory).toBe("~/dev/api");
+    // No `metadata.name`: the sidebar's fallback is the command line.
+    expect(candidate.fields.name).toBe("hx src/");
+  });
+
+  it("builds candidates in the empty-query order", () => {
+    const a = session("a", { last_focused_at: "2026-01-01T10:00:00Z" });
+    const b = session("b", { last_focused_at: "2026-01-01T11:00:00Z" });
+    expect(sessionBarCandidates([a, b]).map((c) => c.session.id)).toEqual(["b", "a"]);
+  });
+});
+
+describe("rows and grouping", () => {
+  it("an empty query keeps every session in input order", () => {
+    const candidates = sessionBarCandidates([session("a"), session("b")]);
+    expect(barRows("", candidates).map((r) => r.candidate.session.id)).toEqual(["a", "b"]);
+  });
+
+  it("groups by kind without reordering the ranking", () => {
+    const candidates = sessionBarCandidates([
+      session("worker", { metadata: { name: "worker" }, current_cwd: "/home/me/dev/api" }),
+      session("api", { metadata: { name: "api" }, current_cwd: "/home/me/dev/web" }),
+    ]);
+    const rows = barRows("api", candidates);
+    const groups = barGroups(rows);
+    expect(groups).toHaveLength(1);
+    expect(groups[0].title).toBe("Sessions");
+    expect(groups[0].results.map((r) => r.candidate.session.id)).toEqual(
+      rows.map((r) => r.candidate.session.id),
+    );
+    // F6: the name beats the directory, and the directory match highlights
+    // inside the directory.
+    expect(groups[0].results[0].candidate.session.id).toBe("api");
+    expect(groups[0].results[1].field).toBe("directory");
+  });
+});
+
+describe("the overlay", () => {
+  const sessions = [
+    session("api", {
+      metadata: { name: "api" },
+      current_cwd: "/home/me/dev/api",
+      last_focused_at: "2026-01-01T11:00:00Z",
+    }),
+    session("worker", {
+      metadata: { name: "worker" },
+      current_cwd: "/home/me/dev/worker",
+      last_focused_at: "2026-01-01T10:00:00Z",
+    }),
+    session("notes", { metadata: { name: "notes" }, current_cwd: "/home/me/notes" }),
+  ];
+
+  // Sessions only: the mixed list's command half is the sigil describe's
+  // business, and the registry is whatever another test file happened to bind.
+  function open(over: Parameters<typeof openCommandBar>[0] | null = null) {
+    return openCommandBar(
+      over ?? { sessions, homeDir: "/home/me", commands: [], onOpenSession: () => {} },
+    );
+  }
+
+  it("is a registry command, so the help overlay lists it", () => {
+    const spec = COMMAND_SPECS.find((s) => s.id === "bar.open");
+    expect(spec?.keys).toEqual(["ctrl-k"]);
+    expect(spec?.scope).toBe("global");
+  });
+
+  it("lists sessions by recency under a kind header on an empty query", () => {
+    open();
+    expect([...document.querySelectorAll(".cmdbar-group-title")].map((h) => h.textContent)).toEqual([
+      "Sessions",
+    ]);
+    expect(rowNames()).toEqual(["api", "worker", "notes"]);
+    expect(activeName()).toBe("api");
+  });
+
+  it("opening twice leaves one overlay", () => {
+    open();
+    open();
+    expect(document.querySelectorAll(".cmdbar-overlay")).toHaveLength(1);
+    expect(isCommandBarOpen()).toBe(true);
+  });
+
+  it("ranks a typed query through the matcher and highlights the matched range", () => {
+    open();
+    type("wor");
+    expect(rowNames()).toEqual(["worker"]);
+    const marks = [...document.querySelectorAll(".cmdbar-row-name mark")].map((m) => m.textContent);
+    expect(marks).toEqual(["wor"]);
+  });
+
+  it("highlights inside the directory when that is the field that matched", () => {
+    open();
+    type("notes");
+    const row = document.querySelector(".cmdbar-row") as HTMLElement;
+    expect(row.dataset.sessionId).toBe("notes");
+    type("dev/wor");
+    expect(rowNames()).toEqual(["worker"]);
+    expect(
+      [...document.querySelectorAll(".cmdbar-row-meta mark")].map((m) => m.textContent).join(""),
+    ).toBe("dev/wor");
+  });
+
+  it("renders a no-results state rather than an empty list", () => {
+    open();
+    type("zzz");
+    expect(rowNames()).toEqual([]);
+    expect(document.querySelector(".cmdbar-empty")?.textContent).toBe("No matches");
+  });
+
+  it("moves the highlight with the arrows and ctrl-p/ctrl-n, without wrapping", () => {
+    open();
+    press("ArrowUp");
+    expect(activeName()).toBe("api");
+    press("ArrowDown");
+    expect(activeName()).toBe("worker");
+    press("n", { ctrlKey: true });
+    expect(activeName()).toBe("notes");
+    press("ArrowDown");
+    expect(activeName()).toBe("notes");
+    press("p", { ctrlKey: true });
+    expect(activeName()).toBe("worker");
+  });
+
+  it("puts the highlight back on the best row whenever the query changes", () => {
+    open();
+    press("ArrowDown");
+    expect(activeName()).toBe("worker");
+    type("o");
+    expect(activeName()).toBe(document.querySelector(".cmdbar-row-name")?.textContent);
+  });
+
+  it("opens the highlighted session through the shared open path on Enter", () => {
+    const seen: string[] = [];
+    const listener = (e: Event) => seen.push((e as CustomEvent<string>).detail);
+    document.addEventListener(SESSION_SELECT_EVENT, listener);
+    openCommandBar({ sessions, homeDir: "/home/me", commands: [] });
+    press("ArrowDown");
+    press("Enter");
+    document.removeEventListener(SESSION_SELECT_EVENT, listener);
+    expect(seen).toEqual(["worker"]);
+    expect(isCommandBarOpen()).toBe(false);
+  });
+
+  it("Enter on an empty result list does nothing", () => {
+    const onOpenSession = vi.fn();
+    open({ sessions, homeDir: "/home/me", commands: [], onOpenSession });
+    type("zzz");
+    press("Enter");
+    expect(onOpenSession).not.toHaveBeenCalled();
+    expect(isCommandBarOpen()).toBe(true);
+  });
+
+  it("closes on Escape and on a press outside the panel", () => {
+    open();
+    press("Escape");
+    expect(isCommandBarOpen()).toBe(false);
+
+    open();
+    (document.querySelector(".cmdbar-overlay") as HTMLElement).dispatchEvent(
+      new MouseEvent("mousedown", { bubbles: true }),
+    );
+    expect(isCommandBarOpen()).toBe(false);
+  });
+
+  it("stays open for a press inside the panel", () => {
+    open();
+    (document.querySelector(".cmdbar-panel") as HTMLElement).dispatchEvent(
+      new MouseEvent("mousedown", { bubbles: true }),
+    );
+    expect(isCommandBarOpen()).toBe(true);
+  });
+
+  it("returns the keyboard to whatever held it when it opened", () => {
+    const before = document.createElement("button");
+    document.body.appendChild(before);
+    before.focus();
+    open();
+    expect(document.activeElement).toBe(document.querySelector(".cmdbar-input"));
+    press("Escape");
+    expect(document.activeElement).toBe(before);
+  });
+
+  it("clicking a row opens that session", () => {
+    const onOpenSession = vi.fn();
+    open({ sessions, homeDir: "/home/me", commands: [], onOpenSession });
+    (document.querySelectorAll(".cmdbar-row")[1] as HTMLElement).click();
+    expect(onOpenSession).toHaveBeenCalledWith("worker");
+    expect(isCommandBarOpen()).toBe(false);
+  });
+});
+
+// ---- the sigils (#150) ----
+
+function command(id: string, label: string, keys: string[], run = () => {}): Command {
+  return { id, label, group: "Test", keys, scope: "global", run };
+}
+
+const flush = () => new Promise((resolve) => setTimeout(resolve, 0));
+
+function rowKeys(): string[][] {
+  return [...document.querySelectorAll(".cmdbar-row-keys")].map((el) =>
+    [...el.querySelectorAll("kbd")].map((k) => k.textContent ?? ""),
+  );
+}
+
+describe("parsing the query line", () => {
+  it("reads a sigil only in first position", () => {
+    expect(parseBarQuery(">kill")).toEqual({ sigil: ">", query: "kill" });
+    expect(parseBarQuery("~/dev")).toEqual({ sigil: "~", query: "/dev" });
+    expect(parseBarQuery("")).toEqual({ sigil: null, query: "" });
+    expect(parseBarQuery("api")).toEqual({ sigil: null, query: "api" });
+  });
+
+  it("leaves a sigil character elsewhere in the query literal", () => {
+    expect(parseBarQuery("api>x")).toEqual({ sigil: null, query: "api>x" });
+    // The case that matters: the second `~` of a directory query reaches the
+    // matcher.
+    expect(parseBarQuery("~~/dev")).toEqual({ sigil: "~", query: "~/dev" });
+  });
+
+  it("returns to the mixed list when the sigil is backspaced away", () => {
+    expect(parseBarQuery(">").sigil).toBe(">");
+    expect(parseBarQuery("").sigil).toBeNull();
+  });
+});
+
+describe("command candidates", () => {
+  it("dedupes by action, not by chord", () => {
+    const run = () => {};
+    const kill = command("a.kill", "Kill the session", ["x"], run);
+    const alias = command("b.kill", "Kill the session", ["ctrl-x"], run);
+    const other = command("c.rename", "Rename the session", ["r"]);
+    expect(dedupeCommands([kill, alias, other]).map((c) => c.id)).toEqual(["a.kill", "c.rename"]);
+  });
+
+  it("matches on the label only, and keeps the chord for display", () => {
+    const candidates = commandBarCandidates([command("a", "Open the spawn form", ["ctrl-k"])]);
+    expect(candidates[0].fields).toEqual({ label: "Open the spawn form" });
+    expect(candidates[0].command.keys).toEqual(["ctrl-k"]);
+  });
+});
+
+describe("directory candidates", () => {
+  it("abbreviates the path it shows and keeps the one it spawns in", () => {
+    const c = directoryCandidate("/home/me/dev/api", "/home/me");
+    expect(c).toEqual({ kind: "directory", path: "/home/me/dev/api", fields: { path: "~/dev/api" } });
+  });
+
+  it("expands a typed `~` and dedupes by the directory spawned in", () => {
+    const paths = ["~/dev/api", "/home/me/dev/api", "/tmp/scratch"];
+    expect(directoryBarCandidates(paths, "/home/me").map((c) => c.path)).toEqual([
+      "/home/me/dev/api",
+      "/tmp/scratch",
+    ]);
+  });
+});
+
+describe("the sigils in the overlay", () => {
+  const sessions = [session("api", { metadata: { name: "api" }, current_cwd: "/home/me/dev/api" })];
+  const ran: string[] = [];
+  const commands = [
+    command("spawn.open", "Open the spawn form", ["n"], () => ran.push("spawn.open")),
+    command("list.kill", "Kill the highlighted session", ["x"], () => ran.push("list.kill")),
+  ];
+
+  afterEach(() => {
+    ran.length = 0;
+  });
+
+  function open(over: Partial<Parameters<typeof openCommandBar>[0]> = {}) {
+    return openCommandBar({
+      sessions,
+      homeDir: "/home/me",
+      commands,
+      onOpenSession: () => {},
+      loadDirectories: async () => [],
+      listDirEntries: async () => [],
+      onSpawnDirectory: () => {},
+      ...over,
+    });
+  }
+
+  it("lists every command in registry order under `>`, with its chord and no header", () => {
+    open();
+    type(">");
+    expect(rowNames()).toEqual(["Open the spawn form", "Kill the highlighted session"]);
+    expect(rowKeys()).toEqual([["n"], ["x"]]);
+    expect(document.querySelectorAll(".cmdbar-group-title")).toHaveLength(0);
+  });
+
+  it("matches a command on its label and never on its chord", () => {
+    open();
+    type(">kill");
+    expect(rowNames()).toEqual(["Kill the highlighted session"]);
+    // `n` and `x` are chords, not label text: querying one finds nothing that
+    // the label does not also justify.
+    type(">ctrlx");
+    expect(rowNames()).toEqual([]);
+  });
+
+  it("runs the highlighted command on Enter", () => {
+    open();
+    type(">kill");
+    press("Enter");
+    expect(ran).toEqual(["list.kill"]);
+    expect(isCommandBarOpen()).toBe(false);
+  });
+
+  it("keeps the list mixed with no sigil, and returns to it when the sigil goes", () => {
+    open();
+    type("s");
+    expect([...document.querySelectorAll(".cmdbar-group-title")].map((h) => h.textContent)).toEqual([
+      "Sessions",
+      "Commands",
+    ]);
+    type(">spawn");
+    expect(rowNames()).toEqual(["Open the spawn form"]);
+    // Backspacing the sigil away is ordinary editing.
+    type("spawn");
+    expect(rowNames()).toContain("Open the spawn form");
+    type("");
+    expect(rowNames()).toEqual(["api"]);
+  });
+
+  it("lists recent dirs then projects under `~`", async () => {
+    open({ loadDirectories: async () => ["/home/me/dev/api", "/srv/www"] });
+    type("~");
+    await flush();
+    expect(rowNames()).toEqual(["~/dev/api", "/srv/www"]);
+    expect(document.querySelectorAll(".cmdbar-group-title")).toHaveLength(0);
+  });
+
+  it("fills the list in from /api/dirs as a path is typed", async () => {
+    const asked: string[] = [];
+    open({
+      loadDirectories: async () => ["/home/me/notes"],
+      listDirEntries: async (dir) => {
+        asked.push(dir);
+        return ["maestro", "api"];
+      },
+    });
+    // The second `~` is a literal query character and reaches the matcher.
+    type("~~/dev/mae");
+    await flush();
+    expect(asked).toEqual(["~/dev/"]);
+    expect(rowNames()).toEqual(["~/dev/maestro"]);
+  });
+
+  it("spawns in the highlighted directory on Enter", async () => {
+    const spawned: string[] = [];
+    open({
+      loadDirectories: async () => ["~/dev/api"],
+      onSpawnDirectory: (path) => spawned.push(path),
+    });
+    type("~api");
+    await flush();
+    press("Enter");
+    expect(spawned).toEqual(["/home/me/dev/api"]);
+    expect(isCommandBarOpen()).toBe(false);
+  });
+
+  it("raises the spawn event when the caller supplies no handler", async () => {
+    const seen: string[] = [];
+    const listener = (e: Event) => seen.push((e as CustomEvent<string>).detail);
+    document.addEventListener(SPAWN_DIRECTORY_EVENT, listener);
+    openCommandBar({
+      sessions,
+      homeDir: "/home/me",
+      commands,
+      onOpenSession: () => {},
+      loadDirectories: async () => ["/home/me/dev/api"],
+      listDirEntries: async () => [],
+    });
+    type("~");
+    await flush();
+    press("Enter");
+    document.removeEventListener(SPAWN_DIRECTORY_EVENT, listener);
+    expect(seen).toEqual(["/home/me/dev/api"]);
+  });
+});
+
+describe("the focus round-trip over a pane (#152)", () => {
+  function terminalTextarea(): HTMLTextAreaElement {
+    const ta = document.createElement("textarea");
+    ta.className = "xterm-helper-textarea";
+    document.body.appendChild(ta);
+    return ta;
+  }
+
+  it("hands the keyboard back to the terminal that had it", () => {
+    const ta = terminalTextarea();
+    ta.focus();
+    openCommandBar({ sessions: [], commands: [] });
+    expect(document.activeElement).toBe(document.querySelector(".cmdbar-input"));
+    press("Escape");
+    expect(document.activeElement).toBe(ta);
+  });
+
+  it("reports no focus change to the daemon, opening or closing", () => {
+    const fetchMock = vi.fn(() => Promise.resolve(new Response(null, { status: 204 })));
+    vi.stubGlobal("fetch", fetchMock);
+    try {
+      const ta = terminalTextarea();
+      ta.focus();
+      openCommandBar({ sessions: [], commands: [] });
+      press("Escape");
+      const focusCalls = fetchMock.mock.calls.filter(([url]: unknown[]) =>
+        String(url).includes("/focus"),
+      );
+      expect(focusCalls).toEqual([]);
+    } finally {
+      vi.unstubAllGlobals();
+    }
+  });
+});
+
+describe("the session action page (#151)", () => {
+  const sessions = [
+    session("api", {
+      metadata: { name: "api" },
+      current_cwd: "/home/me/dev/api",
+      last_focused_at: "2026-01-01T11:00:00Z",
+    }),
+    session("worker", {
+      metadata: { name: "worker" },
+      current_cwd: "/home/me/dev/worker",
+      last_focused_at: "2026-01-01T10:00:00Z",
+    }),
+  ];
+
+  function open(over: Partial<Parameters<typeof openCommandBar>[0]> = {}) {
+    return openCommandBar({
+      sessions,
+      homeDir: "/home/me",
+      commands: [],
+      onOpenSession: () => {},
+      ...over,
+    });
+  }
+
+  function headerText(): string | undefined {
+    return document.querySelector(".cmdbar-page-header")?.textContent ?? undefined;
+  }
+
+  it("lists kill, rename and spawn similar for the highlighted session", () => {
+    open();
+    press("Tab");
+    expect(rowNames()).toEqual(["Kill session", "Rename session", "Spawn similar"]);
+    expect(activeName()).toBe("Kill session");
+  });
+
+  it("names the session being acted on", () => {
+    open();
+    press("ArrowDown");
+    press("Tab");
+    expect(headerText()).toContain("worker");
+  });
+
+  it("drops the kind headers, since the page is one kind", () => {
+    open();
+    press("Tab");
+    expect(document.querySelectorAll(".cmdbar-group-title")).toHaveLength(0);
+  });
+
+  it("stays fuzzy-searchable over the three actions", () => {
+    open();
+    press("Tab");
+    type("ren");
+    expect(rowNames()).toEqual(["Rename session"]);
+    type("spwn");
+    expect(rowNames()).toEqual(["Spawn similar"]);
+    type("zzz");
+    expect(document.querySelector(".cmdbar-empty")?.textContent).toBe("No matches");
+  });
+
+  it("does nothing on a command row", () => {
+    openCommandBar({
+      sessions,
+      homeDir: "/home/me",
+      commands: [{ ...COMMAND_SPECS[0], run: () => {} } as Command],
+      onOpenSession: () => {},
+    });
+    type(">");
+    const before = rowNames();
+    press("Tab");
+    expect(rowNames()).toEqual(before);
+    expect(headerText()).toBeUndefined();
+  });
+
+  it("does nothing on a directory row", async () => {
+    open({ loadDirectories: () => Promise.resolve(["/home/me/dev/api"]) });
+    type("~");
+    await Promise.resolve();
+    press("Tab");
+    expect(rowNames()).toEqual(["~/dev/api"]);
+    expect(headerText()).toBeUndefined();
+  });
+
+  it("returns to the result list on Escape, with the previous query intact", () => {
+    open();
+    type("wor");
+    press("Tab");
+    expect(headerText()).toContain("worker");
+    press("Escape");
+    expect(isCommandBarOpen()).toBe(true);
+    expect(headerText()).toBeUndefined();
+    expect((document.querySelector(".cmdbar-input") as HTMLInputElement).value).toBe("wor");
+    expect(rowNames()).toEqual(["worker"]);
+  });
+
+  it("returns to the result list on backspace at an empty query", () => {
+    open();
+    type("wor");
+    press("Tab");
+    type("");
+    press("Backspace");
+    expect(headerText()).toBeUndefined();
+    expect((document.querySelector(".cmdbar-input") as HTMLInputElement).value).toBe("wor");
+    expect(rowNames()).toEqual(["worker"]);
+  });
+
+  it("keeps backspace ordinary while the page's query has text", () => {
+    open();
+    press("Tab");
+    type("ren");
+    press("Backspace");
+    expect(headerText()).toContain("api");
+    expect(rowNames()).toEqual(["Rename session"]);
+  });
+
+  it("closes the bar when the page's Escape has already been used", () => {
+    open();
+    press("Tab");
+    press("Escape");
+    press("Escape");
+    expect(isCommandBarOpen()).toBe(false);
+  });
+
+  it("raises kill, rename and spawn similar with the session, closing the bar", () => {
+    const seen: string[] = [];
+    for (const [hook, key] of [
+      ["onKillSession", "Kill session"],
+      ["onRenameSession", "Rename session"],
+      ["onSpawnSimilar", "Spawn similar"],
+    ] as const) {
+      open({ [hook]: (s: Session) => seen.push(`${hook}:${s.id}`) });
+      type("wor");
+      press("Tab");
+      type(key);
+      press("Enter");
+      expect(isCommandBarOpen()).toBe(false);
+    }
+    expect(seen).toEqual([
+      "onKillSession:worker",
+      "onRenameSession:worker",
+      "onSpawnSimilar:worker",
+    ]);
+  });
+
+  it("hands each action to the flow it already has, by default", () => {
+    const seen: string[] = [];
+    const listeners: Array<[string, EventListener]> = [
+      [KILL_SESSION_EVENT, (e) => seen.push(`kill:${(e as CustomEvent<Session>).detail.id}`)],
+      [RENAME_SESSION_EVENT, (e) => seen.push(`rename:${(e as CustomEvent<Session>).detail.id}`)],
+      [SPAWN_SIMILAR_EVENT, (e) => seen.push(`similar:${(e as CustomEvent<Session>).detail.id}`)],
+    ];
+    for (const [name, fn] of listeners) document.addEventListener(name, fn);
+    try {
+      for (const action of ["Kill session", "Rename session", "Spawn similar"]) {
+        open();
+        press("Tab");
+        type(action);
+        press("Enter");
+      }
+    } finally {
+      for (const [name, fn] of listeners) document.removeEventListener(name, fn);
+    }
+    expect(seen).toEqual(["kill:api", "rename:api", "similar:api"]);
+  });
+
+  it("offers no action beyond the three", () => {
+    expect(sessionActionCandidates().map((c) => c.action.id)).toEqual([
+      "kill",
+      "rename",
+      "spawn-similar",
+    ]);
+  });
+});

web/src/commandBar.ts

@@ -0,0 +1,809 @@
+// The `ctrl-k` command bar (docs/COMMAND-BAR.md): a query line over a result
+// list, opened from the sidebar, closed with Escape.
+//
+// Three kinds live here: sessions and commands, ranked together by default,
+// and directories, which need the `~` sigil. `tab` on a session drills into
+// its action page (#151), which is the same overlay over three actions.
+
+import { listDir, projects as fetchProjects, recentDirs } from "./api.js";
+import {
+  KILL_SESSION_EVENT,
+  RENAME_SESSION_EVENT,
+  SESSION_SELECT_EVENT,
+  SPAWN_SIMILAR_EVENT,
+} from "./catalog.js";
+import { keyCaps, publishedCommands, type Command } from "./commands.js";
+import {
+  matchAndRank,
+  type CandidateKind,
+  type CommandCandidate,
+  type DirectoryCandidate,
+  type MatchRange,
+  type MatchResult,
+  type SessionCandidate,
+} from "./matcher.js";
+import { splitPath } from "./paths.js";
+import { splitCommand } from "./toolIcon.js";
+import { abbreviateCwd, sessionName, sessionTreePath, type Session } from "./types.js";
+
+/** A matcher candidate that remembers what it came from, so a result can be
+ *  acted on without a second lookup. The extra property is invisible to the
+ *  matcher, which only ever reads `kind` and `fields`. */
+export type SessionBarCandidate = SessionCandidate & { session: Session };
+export type CommandBarCandidate = CommandCandidate & { command: Command };
+/** `fields.path` is the abbreviated path the operator reads and the matcher
+ *  ranks; `path` is the one a spawn is made in. */
+export type DirectoryBarCandidate = DirectoryCandidate & { path: string };
+
+/** One row of a session's action page. It is a `command` to the matcher — a
+ *  single `label` field, ranked exactly like a registry command — and carries
+ *  the action it stands for instead of a registry entry. */
+export type ActionBarCandidate = CommandCandidate & { action: SessionAction };
+
+export type BarCandidate =
+  SessionBarCandidate | CommandBarCandidate | ActionBarCandidate | DirectoryBarCandidate;
+export type BarResult = MatchResult<BarCandidate>;
+
+/** Raised when Enter lands on a directory row. The bar picks the directory; the
+ *  shell owns the spawn, which is the same fast-forward path `N` takes. */
+export const SPAWN_DIRECTORY_EVENT = "cmdbar-spawn-directory";
+
+/** One kind's slice of the ranked list, in rank order. */
+export interface BarGroup<C extends BarCandidate = BarCandidate> {
+  kind: CandidateKind;
+  title: string;
+  results: MatchResult<C>[];
+}
+
+const KIND_TITLES: Record<CandidateKind, string> = {
+  session: "Sessions",
+  command: "Commands",
+  directory: "Directories",
+};
+
+// ---- the sigils ----
+
+export type BarSigil = ">" | "~";
+
+export interface BarQuery {
+  /** The sigil in force, or null for the mixed list. */
+  sigil: BarSigil | null;
+  /** What the matcher sees: everything after a sigil, or the whole query. */
+  query: string;
+}
+
+/** Split a raw query line into its sigil and the query proper.
+ *
+ *  A sigil is only a sigil in first position: `>` or `~` anywhere else is a
+ *  literal query character, which is what a directory query with a second `~`
+ *  in it depends on. Backspacing past a sigil needs no special case either —
+ *  the first character goes and the query is a mixed one again. */
+export function parseBarQuery(raw: string): BarQuery {
+  const first = raw[0];
+  if (first === ">" || first === "~") return { sigil: first, query: raw.slice(1) };
+  return { sigil: null, query: raw };
+}
+
+// ---- the session action page ----
+
+/** The actions a session's action page offers, and no others: the bar picks
+ *  one and hands off to the flow that already implements it
+ *  (docs/COMMAND-BAR.md, "Drill-in"). */
+export type SessionActionId = "kill" | "rename" | "spawn-similar";
+
+export interface SessionAction {
+  id: SessionActionId;
+  label: string;
+}
+
+export const SESSION_ACTIONS: readonly SessionAction[] = [
+  { id: "kill", label: "Kill session" },
+  { id: "rename", label: "Rename session" },
+  { id: "spawn-similar", label: "Spawn similar" },
+];
+
+/** The action page's candidates, in the order above — which is the order an
+ *  empty query lists them in, since the matcher keeps input order. */
+export function sessionActionCandidates(): ActionBarCandidate[] {
+  return SESSION_ACTIONS.map((action) => ({
+    kind: "command",
+    action,
+    fields: { label: action.label },
+  }));
+}
+
+/** Narrow a `command` candidate to an action row. Both share the matcher's
+ *  `command` kind, so what separates them is what they carry. */
+export function isActionCandidate(candidate: BarCandidate): candidate is ActionBarCandidate {
+  return candidate.kind === "command" && "action" in candidate;
+}
+
+// ---- candidates ----
+
+function focusedAt(s: Session): number | null {
+  const stamp = s.last_focused_at;
+  if (typeof stamp !== "string" || stamp === "") return null;
+  const ms = Date.parse(stamp);
+  return Number.isNaN(ms) ? null : ms;
+}
+
+function createdAt(s: Session): number {
+  const ms = Date.parse(s.created_at ?? "");
+  return Number.isNaN(ms) ? 0 : ms;
+}
+
+/** The empty-query order (docs/COMMAND-BAR.md, "Empty query"): most recently
+ *  focused first; a session that has never been focused sorts after every
+ *  session that has, most recently created first among those; and a dead
+ *  session sorts after every live one regardless of recency, because a session
+ *  you cannot attach to is not where you just were.
+ *
+ *  This is also the input order for a non-empty query, which is what the
+ *  matcher's last tie-break preserves. */
+export function orderSessionsForBar(sessions: readonly Session[]): Session[] {
+  return [...sessions].sort((a, b) => {
+    const deadA = a.status === "Dead" ? 1 : 0;
+    const deadB = b.status === "Dead" ? 1 : 0;
+    if (deadA !== deadB) return deadA - deadB;
+
+    const focusA = focusedAt(a);
+    const focusB = focusedAt(b);
+    if ((focusA === null) !== (focusB === null)) return focusA === null ? 1 : -1;
+    if (focusA !== null && focusB !== null && focusA !== focusB) return focusB - focusA;
+
+    return createdAt(b) - createdAt(a);
+  });
+}
+
+/** Build one session's candidate: the fields docs/COMMAND-BAR.md's candidate
+ *  table names, with the directory abbreviated the way the sidebar shows it. */
+export function sessionCandidate(s: Session, homeDir?: string): SessionBarCandidate {
+  const treePath = sessionTreePath(s);
+  const directory = treePath ? abbreviateCwd(treePath, homeDir) : undefined;
+  const tool = splitCommand(s.command).tool ?? undefined;
+  return {
+    kind: "session",
+    session: s,
+    fields: {
+      name: sessionName(s),
+      ...(directory ? { directory } : {}),
+      ...(s.command ? { command: s.command } : {}),
+      ...(tool ? { tool } : {}),
+    },
+  };
+}
+
+/** Every session as a candidate, in the empty-query order. */
+export function sessionBarCandidates(
+  sessions: readonly Session[],
+  homeDir?: string,
+): SessionBarCandidate[] {
+  return orderSessionsForBar(sessions).map((s) => sessionCandidate(s, homeDir));
+}
+
+/** Drop the commands that would list twice. Several chords can be bound to one
+ *  action — the registry already carries its aliases on one entry, but nothing
+ *  stops two entries running the same handler, and listed naively that is two
+ *  identical rows. The dedupe is by **action**, never by chord: the chord is
+ *  displayed, so a command with two of them is still one row. */
+export function dedupeCommands(commands: readonly Command[]): Command[] {
+  const seenRun = new Set<Command["run"]>();
+  const seenLabel = new Set<string>();
+  const kept: Command[] = [];
+  for (const command of commands) {
+    if (seenRun.has(command.run) || seenLabel.has(command.label)) continue;
+    seenRun.add(command.run);
+    seenLabel.add(command.label);
+    kept.push(command);
+  }
+  return kept;
+}
+
+/** Every bound command as a candidate, in registry order. Only the label is a
+ *  field: the chord is displayed beside the row, never matched, because
+ *  matching it would make `>` results depend on a user's rebinds. */
+export function commandBarCandidates(commands: readonly Command[]): CommandBarCandidate[] {
+  return dedupeCommands(commands).map((command) => ({
+    kind: "command",
+    command,
+    fields: { label: command.label },
+  }));
+}
+
+/** `~/dev/api` back to `/home/me/dev/api` — the inverse of `abbreviateCwd`, for
+ *  a path the operator typed or `/api/dirs` completed. */
+export function expandHome(path: string, homeDir?: string): string {
+  if (!homeDir) return path;
+  if (path === "~") return homeDir;
+  return path.startsWith("~/") ? `${homeDir}${path.slice(1)}` : path;
+}
+
+export function directoryCandidate(path: string, homeDir?: string): DirectoryBarCandidate {
+  const absolute = expandHome(path, homeDir);
+  return { kind: "directory", path: absolute, fields: { path: abbreviateCwd(absolute, homeDir) } };
+}
+
+/** Candidates for `~`, deduped by the directory they spawn in and keeping the
+ *  first mention of each — recent dirs (newest first) ahead of the project
+ *  list, which is the empty-query order the contract asks for. */
+export function directoryBarCandidates(
+  paths: readonly string[],
+  homeDir?: string,
+): DirectoryBarCandidate[] {
+  const seen = new Set<string>();
+  const out: DirectoryBarCandidate[] = [];
+  for (const path of paths) {
+    if (path === "") continue;
+    const candidate = directoryCandidate(path, homeDir);
+    if (seen.has(candidate.path)) continue;
+    seen.add(candidate.path);
+    out.push(candidate);
+  }
+  return out;
+}
+
+/** The directory list the bar starts from: what the spawn form already knows —
+ *  `GET /api/recent-dirs` and the project list — either alone if the other
+ *  fails. */
+export async function loadBarDirectories(): Promise<string[]> {
+  const [recents, discovered] = await Promise.all([
+    recentDirs()
+      .then((r) => r.dirs.map((d) => d.cwd))
+      .catch(() => [] as string[]),
+    fetchProjects()
+      .then((list) => list.map((p) => p.path))
+      .catch(() => [] as string[]),
+  ]);
+  return [...recents, ...discovered];
+}
+
+// ---- grouping ----
+
+/** Bucket a ranked list by kind for rendering. Grouping is a rendering of the
+ *  ranking, never a reordering of it: a group holds its matches in rank order,
+ *  and groups appear in the order their best-scoring member does — so the first
+ *  row under the first header is the globally best result. */
+export function barGroups<C extends BarCandidate>(
+  results: readonly MatchResult<C>[],
+): BarGroup<C>[] {
+  const groups: BarGroup<C>[] = [];
+  for (const result of results) {
+    const kind = result.candidate.kind;
+    let group = groups.find((g) => g.kind === kind);
+    if (!group) {
+      group = { kind, title: KIND_TITLES[kind], results: [] };
+      groups.push(group);
+    }
+    group.results.push(result);
+  }
+  return groups;
+}
+
+/** The rows a query produces, flat and in rank order — what the highlight walks
+ *  and what Enter acts on. Headers are labels, not rows, so they are never in
+ *  this list. */
+export function barRows<C extends BarCandidate>(
+  query: string,
+  candidates: readonly C[],
+): MatchResult<C>[] {
+  return matchAndRank(query, candidates);
+}
+
+// ---- rendering ----
+
+/** Text with its matched ranges wrapped in `<mark>`. Ranges come from the
+ *  matcher as `[start, end)` character pairs over the field that won. */
+export function renderHighlighted(text: string, ranges: readonly MatchRange[]): DocumentFragment {
+  const frag = document.createDocumentFragment();
+  let cursor = 0;
+  for (const [start, end] of ranges) {
+    if (start > cursor) frag.append(text.slice(cursor, start));
+    const mark = document.createElement("mark");
+    mark.className = "cmdbar-hit";
+    mark.textContent = text.slice(start, end);
+    frag.append(mark);
+    cursor = end;
+  }
+  if (cursor < text.length) frag.append(text.slice(cursor));
+  return frag;
+}
+
+/** The name line of a row: the session's name, the command's label, or the
+ *  directory's path. */
+function rowName(candidate: BarCandidate): string {
+  switch (candidate.kind) {
+    case "session":
+      return candidate.fields.name;
+    case "command":
+      return candidate.fields.label;
+    case "directory":
+      return candidate.fields.path;
+  }
+}
+
+/** The secondary line under a session row: the field the match was found in
+ *  when that was not the name, so a session found through its directory says
+ *  so. Only sessions have one — a command shows keycaps instead, and a
+ *  directory's path is already the name. */
+function metaText(result: BarResult): string | undefined {
+  if (result.candidate.kind !== "session") return undefined;
+  const fields = result.candidate.fields;
+  switch (result.field) {
+    case "directory":
+      return fields.directory;
+    case "command":
+      return fields.command;
+    case "tool":
+      return fields.tool;
+    default:
+      return fields.directory;
+  }
+}
+
+function renderRow(result: BarResult, index: number): HTMLElement {
+  const candidate = result.candidate;
+  const row = document.createElement("div");
+  row.className = "cmdbar-row";
+  row.setAttribute("role", "option");
+  row.id = `cmdbar-row-${index}`;
+  row.dataset.index = String(index);
+  row.dataset.kind = candidate.kind;
+  if (candidate.kind === "session") {
+    row.dataset.sessionId = candidate.session.id;
+    if (candidate.session.status === "Dead") row.classList.add("is-dead");
+  } else if (isActionCandidate(candidate)) {
+    row.dataset.actionId = candidate.action.id;
+  } else if (candidate.kind === "command") {
+    row.dataset.commandId = candidate.command.id;
+  } else {
+    row.dataset.path = candidate.path;
+  }
+
+  const name = document.createElement("span");
+  name.className = "cmdbar-row-name";
+  const nameText = rowName(candidate);
+  const nameMatched =
+    result.field === "name" || result.field === "label" || result.field === "path";
+  name.append(nameMatched ? renderHighlighted(nameText, result.ranges) : nameText);
+  row.appendChild(name);
+
+  // The chord is teaching material, not a match target: it is rendered from
+  // the live registry entry and never fed to the matcher.
+  if (candidate.kind === "command" && !isActionCandidate(candidate)) {
+    const keys = document.createElement("span");
+    keys.className = "cmdbar-row-keys";
+    for (const cap of keyCaps(candidate.command.keys[0])) {
+      const kbd = document.createElement("kbd");
+      kbd.textContent = cap;
+      keys.appendChild(kbd);
+    }
+    row.appendChild(keys);
+    return row;
+  }
+
+  const meta = metaText(result);
+  if (meta) {
+    const el = document.createElement("span");
+    el.className = "cmdbar-row-meta";
+    const highlighted = result.field !== undefined && result.field !== "name";
+    el.append(highlighted ? renderHighlighted(meta, result.ranges) : meta);
+    row.appendChild(el);
+  }
+  return row;
+}
+
+const PLACEHOLDERS: Record<"mixed" | BarSigil, string> = {
+  mixed: "Go to a session…",
+  ">": "Run a command…",
+  "~": "Spawn in a directory…",
+};
+
+// ---- the overlay ----
+
+export interface CommandBarOptions {
+  /** Sessions to build candidates from, as the store has them right now. */
+  sessions: readonly Session[];
+  /** The daemon's home dir, for the directory field's `~/…` abbreviation. */
+  homeDir?: string;
+  /** Open the highlighted session. Defaults to the shared open path — the
+   *  sidebar's click event — which is what the contract requires; tests pass
+   *  their own. */
+  onOpenSession?: (sessionId: string) => void;
+  /** The command registry to list under `>`. Defaults to every bound command,
+   *  in registry order. */
+  commands?: readonly Command[];
+  /** The directory list behind `~`, fetched once on first use. */
+  loadDirectories?: () => Promise<string[]>;
+  /** One directory's subdirectories, for filling the list in as a path is
+   *  typed. Defaults to `GET /api/dirs`. */
+  listDirEntries?: (dir: string) => Promise<string[]>;
+  /** Spawn a session in the highlighted directory. Defaults to raising
+   *  `SPAWN_DIRECTORY_EVENT`, which the shell turns into a fast-forward
+   *  spawn. */
+  onSpawnDirectory?: (path: string) => void;
+  /** The action page's three actions (#151). Each defaults to raising the
+   *  event the flow that already implements it listens on — the sidebar's
+   *  confirm-and-blockers kill, its inline rename prompt, the spawn form
+   *  seeded from the session. The bar picks the action and nothing more. */
+  onKillSession?: (session: Session) => void;
+  onRenameSession?: (session: Session) => void;
+  onSpawnSimilar?: (session: Session) => void;
+}
+
+interface OpenBar {
+  el: HTMLElement;
+  dispose: () => void;
+}
+
+let current: OpenBar | null = null;
+
+export function isCommandBarOpen(): boolean {
+  return current !== null;
+}
+
+export function closeCommandBar(): void {
+  current?.dispose();
+}
+
+/** Mount the bar. Opening while one is up replaces it, so a stray second call
+ *  can never stack two overlays. */
+export function openCommandBar(opts: CommandBarOptions): HTMLElement {
+  closeCommandBar();
+
+  // Closing returns the keyboard to whatever held it when the bar opened: a
+  // round trip through the bar never silently moves focus.
+  const previouslyFocused = document.activeElement as HTMLElement | null;
+  const openSession =
+    opts.onOpenSession ??
+    ((id: string) => document.dispatchEvent(new CustomEvent(SESSION_SELECT_EVENT, { detail: id })));
+  const spawnDirectory =
+    opts.onSpawnDirectory ??
+    ((path: string) =>
+      document.dispatchEvent(new CustomEvent(SPAWN_DIRECTORY_EVENT, { detail: path })));
+  const sessionEvent =
+    (name: string) =>
+    (session: Session): void => {
+      document.dispatchEvent(new CustomEvent(name, { detail: session }));
+    };
+  const killSession = opts.onKillSession ?? sessionEvent(KILL_SESSION_EVENT);
+  const renameSession = opts.onRenameSession ?? sessionEvent(RENAME_SESSION_EVENT);
+  const spawnSimilar = opts.onSpawnSimilar ?? sessionEvent(SPAWN_SIMILAR_EVENT);
+  const loadDirectories = opts.loadDirectories ?? loadBarDirectories;
+  const listEntries =
+    opts.listDirEntries ?? ((dir: string) => listDir(dir).then((listing) => listing.entries));
+
+  const sessionCandidates: SessionBarCandidate[] = sessionBarCandidates(
+    opts.sessions,
+    opts.homeDir,
+  );
+  const commandCandidates: CommandBarCandidate[] = commandBarCandidates(
+    opts.commands ?? publishedCommands(),
+  );
+
+  const el = document.createElement("div");
+  el.className = "cmdbar-overlay";
+  el.setAttribute("role", "dialog");
+  el.setAttribute("aria-modal", "true");
+  el.setAttribute("aria-label", "Command bar");
+
+  const panel = document.createElement("div");
+  panel.className = "cmdbar-panel";
+
+  const input = document.createElement("input");
+  input.type = "text";
+  input.className = "cmdbar-input";
+  input.setAttribute("role", "combobox");
+  input.setAttribute("aria-expanded", "true");
+  input.setAttribute("aria-controls", "cmdbar-results");
+  input.setAttribute("aria-label", "Search sessions, commands and directories");
+  input.setAttribute("autocomplete", "off");
+  input.spellcheck = false;
+  input.placeholder = PLACEHOLDERS.mixed;
+
+  const results = document.createElement("div");
+  results.className = "cmdbar-results";
+  results.id = "cmdbar-results";
+  results.setAttribute("role", "listbox");
+
+  panel.append(input, results);
+  el.appendChild(panel);
+  document.body.appendChild(el);
+
+  let rows: BarResult[] = [];
+  let highlighted = 0;
+
+  // The action page (#151). `page` is the session being acted on, `stashed`
+  // the result-list query it was drilled into from — backing out restores it,
+  // so the round trip costs the operator nothing.
+  let page: Session | null = null;
+  let stashed = "";
+  let header: HTMLElement | null = null;
+
+  // `~`'s candidates: the recents-and-projects list, fetched once, plus
+  // whatever `/api/dirs` has filled in for the directory being typed.
+  let directories: DirectoryBarCandidate[] = [];
+  let directoriesRequested = false;
+  let probed: DirectoryBarCandidate[] = [];
+  let probedDir: string | null = null;
+  const listings = new Map<string, string[]>();
+
+  function alive(): boolean {
+    return current?.el === el;
+  }
+
+  /** Fetch the recents-and-projects list the first time `~` is used. */
+  function ensureDirectories(): void {
+    if (directoriesRequested) return;
+    directoriesRequested = true;
+    loadDirectories()
+      .then((paths) => {
+        directories = directoryBarCandidates(paths, opts.homeDir);
+        if (alive()) render();
+      })
+      .catch(() => {
+        /* no directories is a shorter list, not an error state */
+      });
+  }
+
+  /** Fill the list in from `GET /api/dirs` once the query looks like a path:
+   *  the directory it names is listed and its children join the candidates, so
+   *  `~` reaches a directory that was never spawned in. */
+  function probeDirectories(query: string): void {
+    const { dir } = splitPath(query);
+    if (dir === "") {
+      probed = [];
+      probedDir = null;
+      return;
+    }
+    if (dir === probedDir) return;
+    probedDir = dir;
+    const cached = listings.get(dir);
+    if (cached) {
+      probed = directoryBarCandidates(
+        cached.map((entry) => `${dir}${entry}`),
+        opts.homeDir,
+      );
+      return;
+    }
+    probed = [];
+    listEntries(dir)
+      .then((entries) => {
+        listings.set(dir, entries);
+        if (!alive() || probedDir !== dir) return;
+        probed = directoryBarCandidates(
+          entries.map((entry) => `${dir}${entry}`),
+          opts.homeDir,
+        );
+        render();
+      })
+      .catch(() => {
+        /* an unreadable directory contributes nothing */
+      });
+  }
+
+  /** What the matcher sees for the query line as it stands. With no sigil the
+   *  list is mixed — sessions and commands together — except on an empty query,
+   *  where the bar is a session switcher. */
+  function candidatesFor(parsed: BarQuery): BarCandidate[] {
+    if (page) return sessionActionCandidates();
+    switch (parsed.sigil) {
+      case ">":
+        return [...commandCandidates];
+      case "~": {
+        ensureDirectories();
+        probeDirectories(parsed.query);
+        const seen = new Set<string>();
+        return [...directories, ...probed].filter((c) =>
+          seen.has(c.path) ? false : (seen.add(c.path), true),
+        );
+      }
+      default:
+        return parsed.query === ""
+          ? [...sessionCandidates]
+          : [...sessionCandidates, ...commandCandidates];
+    }
+  }
+
+  function paintHighlight(): void {
+    for (const row of results.querySelectorAll<HTMLElement>(".cmdbar-row")) {
+      const active = Number(row.dataset.index) === highlighted;
+      row.classList.toggle("is-active", active);
+      row.setAttribute("aria-selected", active ? "true" : "false");
+      if (active) {
+        row.scrollIntoView({ block: "nearest" });
+        input.setAttribute("aria-activedescendant", row.id);
+      }
+    }
+    if (rows.length === 0) input.removeAttribute("aria-activedescendant");
+  }
+
+  /** The line naming the session being acted on, so the target is never
+   *  ambiguous. Present only while the action page is up. */
+  function paintHeader(): void {
+    header?.remove();
+    header = null;
+    if (!page) return;
+    header = document.createElement("div");
+    header.className = "cmdbar-page-header";
+    header.setAttribute("role", "presentation");
+    header.textContent = `Actions for "${sessionName(page)}"`;
+    panel.insertBefore(header, results);
+  }
+
+  function render(): void {
+    // On the action page the query line is over the three actions, so there is
+    // no sigil to read: `>` and `~` are ordinary characters there.
+    const parsed = page ? { sigil: null, query: input.value } : parseBarQuery(input.value);
+    input.placeholder = page
+      ? `Act on ${sessionName(page)}…`
+      : PLACEHOLDERS[parsed.sigil ?? "mixed"];
+    paintHeader();
+    rows = barRows(parsed.query, candidatesFor(parsed));
+    // The highlight starts on the globally best row every time the list
+    // changes: an old index would point at a different result.
+    highlighted = 0;
+    results.replaceChildren();
+
+    if (rows.length === 0) {
+      const empty = document.createElement("div");
+      empty.className = "cmdbar-empty";
+      empty.textContent = "No matches";
+      results.appendChild(empty);
+      paintHighlight();
+      return;
+    }
+
+    let index = 0;
+    for (const group of barGroups(rows)) {
+      // While a sigil is in force there is one kind, so the header is
+      // dropped — and the action page is one kind too.
+      if (parsed.sigil === null && !page) {
+        const header = document.createElement("div");
+        header.className = "cmdbar-group-title";
+        header.setAttribute("role", "presentation");
+        header.textContent = group.title;
+        results.appendChild(header);
+      }
+      for (const result of group.results) {
+        const at = index;
+        const row = renderRow(result, at);
+        row.addEventListener("click", () => activate(at));
+        results.appendChild(row);
+        index += 1;
+      }
+    }
+    paintHighlight();
+  }
+
+  /** The highlight does not wrap: it stops at the first and last row. */
+  function move(delta: number): void {
+    if (rows.length === 0) return;
+    highlighted = Math.min(rows.length - 1, Math.max(0, highlighted + delta));
+    paintHighlight();
+  }
+
+  /** `tab`: drill into the highlighted session's action page. No effect on any
+   *  other kind, and none on the page itself, which has no session rows. */
+  function drillIn(): void {
+    const candidate = rows[highlighted]?.candidate;
+    if (page || candidate?.kind !== "session") return;
+    page = candidate.session;
+    stashed = input.value;
+    input.value = "";
+    render();
+  }
+
+  /** Escape, or backspace at an empty query: back to the result list with the
+   *  query the drill-in was made from. */
+  function leavePage(): void {
+    page = null;
+    input.value = stashed;
+    stashed = "";
+    render();
+  }
+
+  function runAction(action: SessionAction, session: Session): void {
+    close();
+    switch (action.id) {
+      case "kill":
+        killSession(session);
+        return;
+      case "rename":
+        renameSession(session);
+        return;
+      case "spawn-similar":
+        spawnSimilar(session);
+        return;
+    }
+  }
+
+  function activate(index: number): void {
+    const result = rows[index];
+    if (!result) return;
+    const candidate = result.candidate;
+    if (isActionCandidate(candidate)) {
+      // The page cannot be up without a session to act on.
+      if (page) runAction(candidate.action, page);
+      return;
+    }
+    close();
+    switch (candidate.kind) {
+      case "session":
+        openSession(candidate.session.id);
+        return;
+      case "command":
+        candidate.command.run();
+        return;
+      case "directory":
+        spawnDirectory(candidate.path);
+        return;
+    }
+  }
+
+  function onKeydown(e: KeyboardEvent): void {
+    switch (e.key) {
+      case "Escape":
+        e.preventDefault();
+        // On an action page Escape is one level up, not the way out.
+        if (page) leavePage();
+        else close();
+        return;
+      case "Tab":
+        e.preventDefault();
+        drillIn();
+        return;
+      case "Backspace":
+        // Ordinary editing, except at an empty query on the action page.
+        if (page && input.value === "") {
+          e.preventDefault();
+          leavePage();
+        }
+        return;
+      case "Enter":
+        e.preventDefault();
+        activate(highlighted);
+        return;
+      case "ArrowDown":
+        e.preventDefault();
+        move(1);
+        return;
+      case "ArrowUp":
+        e.preventDefault();
+        move(-1);
+        return;
+      case "n":
+        if (e.ctrlKey) {
+          e.preventDefault();
+          move(1);
+        }
+        return;
+      case "p":
+        if (e.ctrlKey) {
+          e.preventDefault();
+          move(-1);
+        }
+        return;
+    }
+  }
+
+  function close(): void {
+    if (current?.el !== el) return;
+    current = null;
+    el.remove();
+    // Restoring focus is what makes the bar a view over the app rather than a
+    // place in it; a detached node cannot take it.
+    if (previouslyFocused?.isConnected) previouslyFocused.focus();
+  }
+
+  input.addEventListener("keydown", onKeydown);
+  input.addEventListener("input", render);
+  // A press on the scrim closes; one inside the panel is left alone.
+  el.addEventListener("mousedown", (ev) => {
+    if (!panel.contains(ev.target as Node)) close();
+  });
+
+  current = { el, dispose: close };
+  render();
+  input.focus();
+  return el;
+}

web/src/commands.test.ts

@@ -0,0 +1,400 @@
+// @vitest-environment happy-dom
+import { describe, expect, it, vi } from "vitest";
+
+import {
+  COMMAND_SPECS,
+  CommandSet,
+  commandSpecs,
+  DEFAULT_LEADER,
+  canonicalizeKey,
+  controlByte,
+  defineCommands,
+  isBarTypingTarget,
+  isTerminalTextarea,
+  isTypingTarget,
+  keyCaps,
+  publishedCommands,
+  type Command,
+} from "./commands.js";
+
+function key(k: string, init: KeyboardEventInit = {}): KeyboardEvent {
+  return new KeyboardEvent("keydown", { key: k, cancelable: true, ...init });
+}
+
+function el(html: string): HTMLElement {
+  const d = document.createElement("div");
+  d.innerHTML = html;
+  return d.firstElementChild as HTMLElement;
+}
+
+/** Dispatch on a target, so `isTypingTarget` sees something other than null. */
+function pressOn(set: CommandSet, target: HTMLElement, k: string, init?: KeyboardEventInit): boolean {
+  const e = key(k, init);
+  Object.defineProperty(e, "target", { value: target });
+  return set.handle(e);
+}
+
+describe("command specs", () => {
+  it("has a unique id and at least one chord per command", () => {
+    const ids = COMMAND_SPECS.map((s) => s.id);
+    expect(new Set(ids).size).toBe(ids.length);
+    for (const spec of COMMAND_SPECS) {
+      expect(spec.keys.length).toBeGreaterThan(0);
+      expect(spec.label.length).toBeGreaterThan(0);
+    }
+  });
+
+  it("binds each chord once within a scope", () => {
+    const seen = new Set<string>();
+    for (const spec of COMMAND_SPECS) {
+      for (const k of spec.keys) {
+        const slot = `${spec.scope}:${k}`;
+        expect(seen.has(slot)).toBe(false);
+        seen.add(slot);
+      }
+    }
+  });
+
+  it("rejects a handler for an id that isn't in the registry", () => {
+    expect(() => defineCommands({ "nope.missing": () => {} })).toThrow(/unknown command id/);
+  });
+
+  it("carries every spec field onto the defined command", () => {
+    const [cmd] = defineCommands({ "spawn.open": () => {} });
+    expect(cmd).toMatchObject({ id: "spawn.open", keys: ["n"], scope: "global" });
+  });
+});
+
+describe("canonicalizeKey", () => {
+  it("spells keys the way the TUI's InputKey::canonical does", () => {
+    expect(canonicalizeKey(key("n"))).toBe("n");
+    expect(canonicalizeKey(key("N", { shiftKey: true }))).toBe("N");
+    expect(canonicalizeKey(key("?", { shiftKey: true }))).toBe("?");
+    expect(canonicalizeKey(key("a", { ctrlKey: true }))).toBe("ctrl-a");
+    expect(canonicalizeKey(key("Escape"))).toBe("esc");
+    expect(canonicalizeKey(key("Enter"))).toBe("enter");
+    expect(canonicalizeKey(key("Tab"))).toBe("tab");
+    expect(canonicalizeKey(key("Tab", { shiftKey: true }))).toBe("backtab");
+    expect(canonicalizeKey(key("ArrowDown"))).toBe("down");
+  });
+
+  it("folds a modified letter to lower case with an explicit shift-", () => {
+    expect(canonicalizeKey(key("H", { ctrlKey: true, shiftKey: true }))).toBe("ctrl-shift-h");
+    expect(canonicalizeKey(key("h", { ctrlKey: true, shiftKey: true }))).toBe("ctrl-shift-h");
+  });
+
+  it("has no canonical form for a modifier pressed alone", () => {
+    expect(canonicalizeKey(key("Control", { ctrlKey: true }))).toBeNull();
+    expect(canonicalizeKey(key("Shift", { shiftKey: true }))).toBeNull();
+  });
+});
+
+describe("keyCaps", () => {
+  it("renders one cap per modifier and key", () => {
+    expect(keyCaps("ctrl-shift-h")).toEqual(["Ctrl", "Shift", "H"]);
+    expect(keyCaps("enter")).toEqual(["Enter"]);
+    expect(keyCaps("j")).toEqual(["j"]);
+    expect(keyCaps("N")).toEqual(["N"]);
+    expect(keyCaps("?")).toEqual(["?"]);
+    expect(keyCaps("ctrl-a ctrl-k")).toEqual(["Ctrl", "A", "then", "Ctrl", "K"]);
+  });
+});
+
+describe("CommandSet", () => {
+  it("runs the command bound to a chord, and swallows the browser default", () => {
+    const run = vi.fn();
+    const set = new CommandSet(defineCommands({ "spawn.open": run }));
+    const e = key("n");
+    expect(set.handle(e)).toBe(true);
+    expect(run).toHaveBeenCalledTimes(1);
+    expect(e.defaultPrevented).toBe(true);
+  });
+
+  it("leaves an unbound key alone", () => {
+    const set = new CommandSet(defineCommands({ "spawn.open": vi.fn() }));
+    const e = key("q");
+    expect(set.handle(e)).toBe(false);
+    expect(e.defaultPrevented).toBe(false);
+  });
+
+  it("treats a modified key as a different binding", () => {
+    const run = vi.fn();
+    const set = new CommandSet(defineCommands({ "spawn.open": run }));
+    expect(set.handle(key("n", { ctrlKey: true }))).toBe(false);
+    expect(set.handle(key("n", { metaKey: true }))).toBe(false);
+    expect(run).not.toHaveBeenCalled();
+  });
+
+  it("runs every alias of a command", () => {
+    const run = vi.fn();
+    const set = new CommandSet(defineCommands({ "list.next": run }));
+    set.handle(key("j"));
+    set.handle(key("ArrowDown"));
+    expect(run).toHaveBeenCalledTimes(2);
+  });
+
+  it("keeps plain keys deaf inside a form field, and leader chords live from the pane", () => {
+    const plain = vi.fn();
+    const chorded = vi.fn();
+    const set = new CommandSet(
+      defineCommands({ "spawn.open": plain, "focus.toggle": chorded }, DEFAULT_LEADER),
+      { leader: DEFAULT_LEADER },
+    );
+    const input = el("<input>");
+    expect(pressOn(set, input, "n")).toBe(false);
+    expect(plain).not.toHaveBeenCalled();
+    // focus.toggle hangs off the leader (#166): a plain, unmodified Escape is
+    // left for the pane's shell/app instead.
+    const terminal = el('<textarea class="xterm-helper-textarea"></textarea>');
+    pressOn(set, terminal, "a", { ctrlKey: true });
+    expect(pressOn(set, terminal, "h")).toBe(true);
+    expect(chorded).toHaveBeenCalledTimes(1);
+  });
+
+  it("leaves a plain Escape for the pane instead of binding it", () => {
+    const set = new CommandSet(defineCommands({ "spawn.open": vi.fn() }));
+    const textarea = el('<textarea class="xterm-helper-textarea"></textarea>');
+    expect(pressOn(set, textarea, "Escape")).toBe(false);
+  });
+});
+
+describe("the leader", () => {
+  it("defaults to the TUI's ctrl-a", () => {
+    expect(DEFAULT_LEADER).toBe("ctrl-a");
+  });
+
+  // #159: the leader is the operator's, served on `/api/info`. Every chord
+  // behind it is built from it, so a rebound leader carries its escape hatches
+  // with it instead of leaving them on a stale ctrl-a.
+  it("builds the chords behind it from the configured leader", () => {
+    const byId = new Map(commandSpecs("ctrl-b").map((s) => [s.id, s]));
+    expect(byId.get("pane.literalCtrlK")?.keys).toEqual(["ctrl-b ctrl-k"]);
+    expect(byId.get("pane.literalLeader")?.keys).toEqual(["ctrl-b ctrl-b"]);
+    expect(byId.get("focus.toggle")?.keys).toEqual(["ctrl-b h"]);
+    // Commands that do not hang off the leader are untouched.
+    expect(byId.get("bar.open")?.keys).toEqual(["ctrl-k"]);
+  });
+
+  it("dispatches a configured leader's chord and not the default's", () => {
+    const literalCtrlK = vi.fn();
+    const set = new CommandSet(defineCommands({ "pane.literalCtrlK": literalCtrlK }, "ctrl-b"), {
+      leader: "ctrl-b",
+    });
+    set.handle(key("b", { ctrlKey: true }));
+    expect(set.handle(key("k", { ctrlKey: true }))).toBe(true);
+    expect(literalCtrlK).toHaveBeenCalledTimes(1);
+
+    // The old leader is an ordinary key again: it holds nothing, and the chord
+    // that used to follow it runs nothing.
+    set.handle(key("a", { ctrlKey: true }));
+    set.handle(key("k", { ctrlKey: true }));
+    expect(literalCtrlK).toHaveBeenCalledTimes(1);
+  });
+
+  it("sends the configured leader's own byte for the doubled chord", () => {
+    expect(controlByte("ctrl-b")).toBe("\x02");
+  });
+
+  it("holds the leader as a partial chord instead of selecting the page", () => {
+    const set = new CommandSet(defineCommands({ "spawn.open": vi.fn() }), {
+      leader: DEFAULT_LEADER,
+    });
+    const e = key("a", { ctrlKey: true });
+    expect(set.handle(e)).toBe(true);
+    expect(e.defaultPrevented).toBe(true);
+  });
+
+  it("swallows the key after the leader rather than running its plain binding", () => {
+    const run = vi.fn();
+    const set = new CommandSet(defineCommands({ "spawn.open": run }), {
+      leader: DEFAULT_LEADER,
+    });
+    set.handle(key("a", { ctrlKey: true }));
+    expect(set.handle(key("n"))).toBe(true);
+    expect(run).not.toHaveBeenCalled();
+    // The next key is an ordinary one again.
+    set.handle(key("n"));
+    expect(run).toHaveBeenCalledTimes(1);
+  });
+
+  it("forgets a held leader once the chord timeout passes", () => {
+    const run = vi.fn();
+    let now = 0;
+    const set = new CommandSet(defineCommands({ "spawn.open": run }), {
+      leader: DEFAULT_LEADER,
+      chordTimeoutMs: 1000,
+      now: () => now,
+    });
+    set.handle(key("a", { ctrlKey: true }));
+    now = 1500;
+    set.handle(key("n"));
+    expect(run).toHaveBeenCalledTimes(1);
+  });
+
+  it("leaves select-all alone in a real form field", () => {
+    const set = new CommandSet(defineCommands({ "spawn.open": vi.fn() }), {
+      leader: DEFAULT_LEADER,
+    });
+    const input = el("<input>");
+    const e = key("a", { ctrlKey: true });
+    Object.defineProperty(e, "target", { value: input });
+    expect(set.handle(e)).toBe(false);
+    expect(e.defaultPrevented).toBe(false);
+  });
+});
+
+describe("publishing", () => {
+  it("lists a constructed set's commands, replacing an id rather than doubling it", () => {
+    new CommandSet(defineCommands({ "list.kill": () => {} }));
+    new CommandSet(defineCommands({ "list.kill": () => {} }));
+    const ids = publishedCommands().map((c) => c.id);
+    expect(ids.filter((id) => id === "list.kill")).toEqual(["list.kill"]);
+  });
+
+  it("keeps published commands in registry order", () => {
+    const order = COMMAND_SPECS.map((s) => s.id);
+    const ids = publishedCommands().map((c) => c.id);
+    expect(ids).toEqual(order.filter((id) => ids.includes(id)));
+  });
+});
+
+describe("isTypingTarget", () => {
+  it("is true for form fields and editable nodes, false otherwise", () => {
+    expect(isTypingTarget(el("<input>"))).toBe(true);
+    expect(isTypingTarget(el("<textarea></textarea>"))).toBe(true);
+    expect(isTypingTarget(el("<select></select>"))).toBe(true);
+    expect(isTypingTarget(el('<div contenteditable="true"></div>'))).toBe(true);
+    expect(isTypingTarget(el("<button></button>"))).toBe(false);
+    expect(isTypingTarget(null)).toBe(false);
+  });
+});
+
+describe("isTerminalTextarea", () => {
+  it("recognises xterm's offscreen textarea, and nothing else", () => {
+    expect(isTerminalTextarea(el('<textarea class="xterm-helper-textarea"></textarea>'))).toBe(true);
+    expect(isTerminalTextarea(el("<textarea></textarea>"))).toBe(false);
+    expect(isTerminalTextarea(el("<input>"))).toBe(false);
+    expect(isTerminalTextarea(null)).toBe(false);
+  });
+});
+
+describe("isBarTypingTarget", () => {
+  it("holds the bar's keys out of real form fields", () => {
+    expect(isBarTypingTarget(el("<input>"))).toBe(true);
+    expect(isBarTypingTarget(el("<textarea></textarea>"))).toBe(true);
+  });
+
+  it("does not count the terminal's textarea, so ctrl-k reaches the bar there", () => {
+    expect(isBarTypingTarget(el('<textarea class="xterm-helper-textarea"></textarea>'))).toBe(false);
+    expect(isBarTypingTarget(el("<button></button>"))).toBe(false);
+    expect(isBarTypingTarget(null)).toBe(false);
+  });
+});
+
+describe("ctrl-k over a focused pane (#152)", () => {
+  const terminal = () => el('<textarea class="xterm-helper-textarea"></textarea>');
+
+  /** The global listener's routing: the bar's set only sees a key that is not
+   *  aimed at a real form field. */
+  function route(set: CommandSet, target: HTMLElement, k: string, init?: KeyboardEventInit) {
+    if (isBarTypingTarget(target)) return false;
+    return pressOn(set, target, k, init);
+  }
+
+  it("opens the bar when the terminal has the keyboard", () => {
+    const open = vi.fn();
+    const set = new CommandSet(defineCommands({ "bar.open": open }));
+    expect(route(set, terminal(), "k", { ctrlKey: true })).toBe(true);
+    expect(open).toHaveBeenCalledTimes(1);
+  });
+
+  it("leaves the spawn form's inputs their own Ctrl-K", () => {
+    const open = vi.fn();
+    const set = new CommandSet(defineCommands({ "bar.open": open }));
+    expect(route(set, el("<input>"), "k", { ctrlKey: true })).toBe(false);
+    expect(open).not.toHaveBeenCalled();
+  });
+
+  it("sends the literal 0x0B after the leader, without opening the bar", () => {
+    const open = vi.fn();
+    const literal = vi.fn();
+    const bar = new CommandSet(defineCommands({ "bar.open": open }));
+    const set = new CommandSet(defineCommands({ "pane.literalCtrlK": literal }), {
+      leader: DEFAULT_LEADER,
+    });
+    const target = terminal();
+    expect(pressOn(set, target, "a", { ctrlKey: true })).toBe(true);
+    const e = key("k", { ctrlKey: true });
+    Object.defineProperty(e, "target", { value: target });
+    expect(set.handle(e)).toBe(true);
+    expect(literal).toHaveBeenCalledTimes(1);
+    // The leader's set consumed the key, so the bar's set never sees it.
+    expect(open).not.toHaveBeenCalled();
+    expect(bar.handle(e)).toBe(true); // sanity: it would have opened otherwise
+    expect(open).toHaveBeenCalledTimes(1);
+  });
+
+  it("binds the escape hatch behind the default leader", () => {
+    const spec = COMMAND_SPECS.find((s) => s.id === "pane.literalCtrlK");
+    expect(spec?.keys).toEqual([`${DEFAULT_LEADER} ctrl-k`]);
+  });
+});
+
+describe("leader pressed twice (#158)", () => {
+  it("sends one literal leader byte and clears the pending chord", () => {
+    const literal = vi.fn();
+    const run = vi.fn();
+    const set = new CommandSet(
+      defineCommands({ "pane.literalLeader": literal, "spawn.open": run }),
+      { leader: DEFAULT_LEADER },
+    );
+    const target = el('<textarea class="xterm-helper-textarea"></textarea>');
+    expect(pressOn(set, target, "a", { ctrlKey: true })).toBe(true);
+    expect(pressOn(set, target, "a", { ctrlKey: true })).toBe(true);
+    expect(literal).toHaveBeenCalledTimes(1);
+    // The chord is cleared, not still held: the next key is ordinary again.
+    expect(set.handle(key("n"))).toBe(true);
+    expect(run).toHaveBeenCalledTimes(1);
+  });
+
+  it("binds the escape hatch behind the default leader", () => {
+    const spec = COMMAND_SPECS.find((s) => s.id === "pane.literalLeader");
+    expect(spec?.keys).toEqual([`${DEFAULT_LEADER} ${DEFAULT_LEADER}`]);
+  });
+
+  // Not just the default: the chord is resolved from whatever leader this
+  // set was constructed with, so a rebound leader carries the escape hatch
+  // with it — the same proof #156 wrote for the TUI. The web has no config
+  // for this yet (#159), but the mechanism must not be hardcoded to ctrl-a.
+  it("follows a rebound leader, not just the default", () => {
+    const literal = vi.fn();
+    const rebound: Command = {
+      id: "pane.literalLeader",
+      label: "Send a literal leader key to the pane",
+      group: "Pane",
+      scope: "global",
+      keys: ["ctrl-b ctrl-b"],
+      run: literal,
+    };
+    const set = new CommandSet([rebound], { leader: "ctrl-b" });
+    const target = el('<textarea class="xterm-helper-textarea"></textarea>');
+    expect(pressOn(set, target, "b", { ctrlKey: true })).toBe(true);
+    expect(pressOn(set, target, "b", { ctrlKey: true })).toBe(true);
+    expect(literal).toHaveBeenCalledTimes(1);
+    // The old leader no longer does anything special.
+    expect(pressOn(set, target, "a", { ctrlKey: true })).toBe(false);
+  });
+});
+
+describe("controlByte", () => {
+  it("computes the raw control byte from a plain ctrl chord", () => {
+    expect(controlByte("ctrl-a")).toBe("\x01");
+    expect(controlByte("ctrl-k")).toBe("\x0b");
+  });
+
+  it("rejects anything that isn't a single plain ctrl chord", () => {
+    expect(() => controlByte("ctrl-shift-a")).toThrow();
+    expect(() => controlByte("a")).toThrow();
+    expect(() => controlByte("ctrl-a ctrl-a")).toThrow();
+  });
+});

web/src/commands.ts

@@ -0,0 +1,440 @@
+// The web client's command registry (#148). One entry per command — a stable
+// id, a plain-language label, the key chord it answers to, and a `run()` — so
+// there is exactly one list of what the client can do. The `?` overlay renders
+// from it (`help.ts`), and every keybinding is dispatched through it; a command
+// added here is bound and documented in the same edit.
+//
+// Keys are canonical strings, the same spelling the TUI's `InputKey::canonical`
+// produces (`ctrl-shift-h`, `enter`, `esc`, `n`, `N`) and chords are those
+// joined by a space (`ctrl-a ctrl-k`). Matching the TUI's spelling is what lets
+// docs/COMMAND-BAR.md describe one key model for both clients.
+
+/** Where a command's keys are listened for. `global` is the window, `list` the
+ *  sidebar's session tree, `pane` the attached terminal, `overlay` the help
+ *  dialog while it is up. */
+export type CommandScope = "global" | "list" | "pane" | "overlay";
+
+export interface CommandSpec {
+  /** Stable identifier. Never rendered; safe to bind config and tests to. */
+  id: string;
+  /** Plain-language label — what the `?` overlay and (later) the command bar
+   *  show. */
+  label: string;
+  /** Help-overlay section. Groups render in the order they first appear here. */
+  group: string;
+  /** Canonical chords that run it. The first is the one shown to the operator;
+   *  the rest are aliases (`j` and `down`). */
+  keys: string[];
+  scope: CommandScope;
+}
+
+export interface Command extends CommandSpec {
+  run: () => void;
+}
+
+/** Leader used when the daemon does not name one — an older daemon, or an
+ *  unreachable `/api/info`. Mirrors the TUI's `[tui].leader` default. `ctrl-a`
+ *  is select-all in a browser, so a set that owns the leader
+ *  `preventDefault`s it. */
+export const DEFAULT_LEADER = "ctrl-a";
+
+/** Every command the web client has, for one leader. The single list: labels,
+ *  chords and grouping live here and nowhere else. Chords behind the leader are
+ *  built from it (#159), so the configured leader — served on `/api/info` as
+ *  `leader` — is what the overlay renders and the sets dispatch. */
+export function commandSpecs(leader: string = DEFAULT_LEADER): readonly CommandSpec[] {
+  return SPECS.map(({ leaderKeys, ...spec }) =>
+    leaderKeys ? { ...spec, keys: leaderKeys(leader) } : spec,
+  );
+}
+
+/** A spec whose chords are fixed, or a spec that builds them from the leader. */
+type SpecSource = CommandSpec & { leaderKeys?: (leader: string) => string[] };
+
+const SPECS: readonly SpecSource[] = [
+  {
+    id: "spawn.open",
+    label: "Open the spawn form",
+    group: "Sessions",
+    keys: ["n"],
+    scope: "global",
+  },
+  {
+    id: "spawn.fastForward",
+    label: "Spawn a session with every default resolved",
+    group: "Sessions",
+    keys: ["N"],
+    scope: "global",
+  },
+  {
+    id: "bar.open",
+    label: "Open the command bar",
+    group: "Sessions",
+    keys: ["ctrl-k"],
+    scope: "global",
+  },
+  {
+    id: "pane.literalCtrlK",
+    label: "Send a literal Ctrl-K to the pane",
+    group: "Pane",
+    keys: [`${DEFAULT_LEADER} ctrl-k`],
+    leaderKeys: (leader) => [`${leader} ctrl-k`],
+    scope: "global",
+  },
+  {
+    id: "pane.literalLeader",
+    label: "Send a literal leader key to the pane",
+    group: "Pane",
+    keys: [`${DEFAULT_LEADER} ${DEFAULT_LEADER}`],
+    leaderKeys: (leader) => [`${leader} ${leader}`],
+    scope: "global",
+  },
+  {
+    id: "focus.toggle",
+    label: "Move the keyboard between the session list and the pane",
+    group: "Session list",
+    keys: [`${DEFAULT_LEADER} h`],
+    leaderKeys: (leader) => [`${leader} h`],
+    scope: "global",
+  },
+  {
+    id: "list.next",
+    label: "Highlight the next session",
+    group: "Session list",
+    keys: ["j", "down"],
+    scope: "list",
+  },
+  {
+    id: "list.prev",
+    label: "Highlight the previous session",
+    group: "Session list",
+    keys: ["k", "up"],
+    scope: "list",
+  },
+  {
+    id: "list.activate",
+    label: "Open the highlighted session, or expand a folder",
+    group: "Session list",
+    keys: ["enter"],
+    scope: "list",
+  },
+  {
+    id: "list.toggleFolder",
+    label: "Collapse or expand the highlighted folder",
+    group: "Session list",
+    keys: ["c"],
+    scope: "list",
+  },
+  {
+    id: "list.rename",
+    label: "Rename the highlighted session",
+    group: "Session list",
+    keys: ["r"],
+    scope: "list",
+  },
+  {
+    id: "list.kill",
+    label: "Kill the highlighted session",
+    group: "Session list",
+    keys: ["x"],
+    scope: "list",
+  },
+  {
+    id: "list.focusPane",
+    label: "Send the keyboard to the pane",
+    group: "Session list",
+    keys: ["tab"],
+    scope: "list",
+  },
+  {
+    id: "help.toggle",
+    label: "Show or hide this help",
+    group: "Help",
+    keys: ["?"],
+    scope: "global",
+  },
+  {
+    id: "help.close",
+    label: "Close the help overlay or an open menu",
+    group: "Help",
+    keys: ["esc"],
+    scope: "overlay",
+  },
+  {
+    id: "debug.toggleHud",
+    label: "Toggle the debug HUD",
+    group: "Debug",
+    keys: ["ctrl-shift-d"],
+    scope: "global",
+  },
+];
+
+/** The command list under the default leader. Iteration order everywhere else
+ *  (the help overlay, the bar) comes from here. */
+export const COMMAND_SPECS: readonly CommandSpec[] = commandSpecs();
+
+/** Attach handlers to specs, by id. Throws on an unknown id, so a typo is a
+ *  test failure rather than a key that silently does nothing. `leader` picks
+ *  the chords behind the leader; omit it for a set that has none. */
+export function defineCommands(
+  handlers: Record<string, () => void>,
+  leader: string = DEFAULT_LEADER,
+): Command[] {
+  const byId = new Map(commandSpecs(leader).map((s) => [s.id, s]));
+  return Object.entries(handlers).map(([id, run]) => {
+    const spec = byId.get(id);
+    if (!spec) throw new Error(`unknown command id: ${id}`);
+    return { ...spec, run };
+  });
+}
+
+// ---- what the help overlay renders ----
+
+const published = new Map<string, Command>();
+
+/** Record commands as bound. Re-registering an id replaces it, so a second
+ *  sidebar (tests, hot reload) doesn't duplicate rows in the overlay. */
+export function publishCommands(cmds: Command[]): void {
+  for (const c of cmds) published.set(c.id, c);
+}
+
+/** Every bound command, in `COMMAND_SPECS` order. */
+export function publishedCommands(): Command[] {
+  return COMMAND_SPECS.map((s) => published.get(s.id)).filter((c): c is Command => c !== undefined);
+}
+
+// ---- key canonicalisation ----
+
+const NAMED: Record<string, string> = {
+  Escape: "esc",
+  Enter: "enter",
+  Tab: "tab",
+  Backspace: "backspace",
+  ArrowUp: "up",
+  ArrowDown: "down",
+  ArrowLeft: "left",
+  ArrowRight: "right",
+  Home: "home",
+  End: "end",
+  PageUp: "pageup",
+  PageDown: "pagedown",
+  Delete: "delete",
+  " ": "space",
+};
+
+/** The canonical string for one keydown. Mirrors the TUI's
+ *  `InputKey::canonical`: modifier prefixes in ctrl/alt/shift order, then the
+ *  key. A shifted character already spells itself (`N`, `?`), so `shift-` is
+ *  only written when another modifier is present and the char was folded to
+ *  lower case. */
+export function canonicalizeKey(e: KeyboardEvent): string | null {
+  if (!e.key) return null;
+  // Modifier keys pressed alone are never a binding.
+  if (e.key === "Control" || e.key === "Alt" || e.key === "Shift" || e.key === "Meta") return null;
+  const named = NAMED[e.key];
+  if (named === "tab" && e.shiftKey) return "backtab";
+  let out = "";
+  if (e.ctrlKey) out += "ctrl-";
+  if (e.altKey) out += "alt-";
+  if (e.metaKey) out += "meta-";
+  if (named) {
+    if (e.shiftKey) out += "shift-";
+    return out + named;
+  }
+  if (e.key.length === 1) {
+    if (out === "") return e.key;
+    if (e.shiftKey) out += "shift-";
+    return out + e.key.toLowerCase();
+  }
+  if (e.shiftKey) out += "shift-";
+  return out + e.key.toLowerCase();
+}
+
+/** The raw control byte for a canonical `ctrl-<letter>` chord — `ctrl-a` is
+ *  `0x01` — mirroring the TUI's `encode_key`. Built from the chord string
+ *  itself so a different leader sends its own byte, not a hardcoded one. */
+export function controlByte(chord: string): string {
+  const m = /^ctrl-([a-z])$/.exec(chord);
+  if (!m) throw new Error(`not a plain ctrl chord: ${chord}`);
+  return String.fromCharCode(m[1].charCodeAt(0) - 96);
+}
+
+const MOD_PREFIX = /^(ctrl|alt|meta|shift)-/;
+
+/** True when a chord carries a modifier or more than one key. Plain single-key
+ *  chords are the ones that stay deaf inside form fields. */
+function isChorded(chord: string): boolean {
+  return chord.includes(" ") || MOD_PREFIX.test(chord);
+}
+
+/** True when the event target swallows plain keystrokes — a form field, or the
+ *  hidden textarea xterm types into. Every plain single-key binding is deaf in
+ *  the same places. */
+export function isTypingTarget(target: EventTarget | null): boolean {
+  const el = target as HTMLElement | null;
+  if (!el || typeof el.tagName !== "string") return false;
+  return (
+    el.tagName === "INPUT" ||
+    el.tagName === "TEXTAREA" ||
+    el.tagName === "SELECT" ||
+    el.isContentEditable
+  );
+}
+
+/** xterm's offscreen textarea. It is a typing target like any other, but it is
+ *  also where the leader has to work — a pane is exactly where the operator
+ *  needs the escape hatch (docs/COMMAND-BAR.md). */
+export function isTerminalTextarea(target: EventTarget | null): boolean {
+  const el = target as HTMLElement | null;
+  return !!el && typeof el.className === "string" && el.classList?.contains("xterm-helper-textarea");
+}
+
+/** True where the command bar's own keys must stay out of the way: a real form
+ *  field, and not the pane. `ctrl-k` is intercepted ahead of xterm
+ *  (docs/COMMAND-BAR.md, "Opening"), so a focused terminal opens the bar, while
+ *  the spawn form's inputs keep their own Ctrl-K. */
+export function isBarTypingTarget(target: EventTarget | null): boolean {
+  return isTypingTarget(target) && !isTerminalTextarea(target);
+}
+
+// ---- display ----
+
+const CAPS: Record<string, string> = {
+  ctrl: "Ctrl",
+  alt: "Alt",
+  meta: "Meta",
+  shift: "Shift",
+  esc: "Esc",
+  enter: "Enter",
+  tab: "Tab",
+  backtab: "Shift Tab",
+  backspace: "Backspace",
+  up: "Up",
+  down: "Down",
+  left: "Left",
+  right: "Right",
+  home: "Home",
+  end: "End",
+  pageup: "PgUp",
+  pagedown: "PgDn",
+  delete: "Del",
+  space: "Space",
+};
+
+/** Keycaps for a chord, left to right: `ctrl-shift-h` → Ctrl, Shift, H. A
+ *  multi-key chord separates its keys with a `then` cap. */
+export function keyCaps(chord: string): string[] {
+  const caps: string[] = [];
+  for (const [i, key] of chord.split(" ").entries()) {
+    if (i > 0) caps.push("then");
+    const parts = key.split("-");
+    // A bare `-` key splits into two empties; treat it as the key itself.
+    if (parts.every((p) => p === "")) {
+      caps.push("-");
+      continue;
+    }
+    const last = parts.pop() as string;
+    const mods = parts.filter((p) => p !== "");
+    for (const m of mods) caps.push(CAPS[m] ?? m);
+    caps.push(CAPS[last] ?? (mods.length > 0 && last.length === 1 ? last.toUpperCase() : last));
+  }
+  return caps;
+}
+
+// ---- dispatch ----
+
+/** How long a partial chord waits for its next key — the TUI's
+ *  `chord_timeout_ms` default. */
+export const DEFAULT_CHORD_TIMEOUT_MS = 1000;
+
+export interface CommandSetOptions {
+  /** Canonical leader key. A set given one holds every leader press as a
+   *  pending chord, whether or not anything is bound behind it yet. */
+  leader?: string | null;
+  chordTimeoutMs?: number;
+  /** Call `preventDefault()` on a handled key. Off for the terminal's own key
+   *  handler, which swallows by returning `false` to xterm instead. */
+  preventDefault?: boolean;
+  /** Clock, for tests. */
+  now?: () => number;
+}
+
+/** A group of commands listening on one surface. Resolves a keydown to a
+ *  command the way the TUI's `ChordState` does: hold while the sequence is a
+ *  strict prefix of some binding, otherwise resolve and dispatch. */
+export class CommandSet {
+  private readonly byChord = new Map<string, Command>();
+  private readonly leader: string | null;
+  private readonly timeout: number;
+  private readonly preventDefault: boolean;
+  private readonly now: () => number;
+  private held: string[] = [];
+  private lastPress = 0;
+
+  constructor(
+    readonly commands: Command[],
+    opts: CommandSetOptions = {},
+  ) {
+    for (const c of commands) for (const k of c.keys) this.byChord.set(k, c);
+    this.leader = opts.leader ?? null;
+    this.timeout = opts.chordTimeoutMs ?? DEFAULT_CHORD_TIMEOUT_MS;
+    this.preventDefault = opts.preventDefault ?? true;
+    this.now = opts.now ?? (() => Date.now());
+    publishCommands(commands);
+  }
+
+  /** Whether any binding starts with `candidate` and continues. */
+  private isPrefix(candidate: string): boolean {
+    const marker = `${candidate} `;
+    for (const chord of this.byChord.keys()) if (chord.startsWith(marker)) return true;
+    return false;
+  }
+
+  /** Feed one keydown. Returns true when the key was consumed — dispatched, or
+   *  held as a partial chord. */
+  handle(e: KeyboardEvent): boolean {
+    const key = canonicalizeKey(e);
+    if (key === null) return false;
+    if (this.held.length > 0 && this.now() - this.lastPress > this.timeout) this.held = [];
+    const candidate = this.held.length > 0 ? `${this.held.join(" ")} ${key}` : key;
+    this.lastPress = this.now();
+
+    // The leader is a prefix by construction, so it stops being select-all
+    // before anything is bound behind it (#149 binds the first chord).
+    if (this.leader !== null && this.held.length === 0 && key === this.leader) {
+      if (isTypingTarget(e.target) && !isTerminalTextarea(e.target)) return false;
+      this.held = [key];
+      if (this.preventDefault) e.preventDefault();
+      return true;
+    }
+
+    if (this.isPrefix(candidate)) {
+      this.held.push(key);
+      if (this.preventDefault) e.preventDefault();
+      return true;
+    }
+
+    const wasChord = this.held.length > 0;
+    this.held = [];
+    const cmd = this.byChord.get(candidate);
+    if (!cmd) {
+      // A chord that resolved to nothing is still consumed: the leader took
+      // the key, so it must not also fall through to a plain binding.
+      return wasChord;
+    }
+    // Plain single-key bindings are deaf where typing happens; chorded ones are
+    // not, and neither are the pane's and the overlay's, which are only fed
+    // from the surface that owns them.
+    if (
+      !isChorded(candidate) &&
+      cmd.scope !== "pane" &&
+      cmd.scope !== "overlay" &&
+      isTypingTarget(e.target)
+    ) {
+      return false;
+    }
+    if (this.preventDefault) e.preventDefault();
+    cmd.run();
+    return true;
+  }
+}

web/src/connections.test.ts

@@ -2,11 +2,83 @@
 import { afterEach, describe, expect, it, vi } from "vitest";
 
 import { ConnectionPool } from "./connections.js";
+import { CatalogStore } from "./events.js";
+import type { Session } from "./types.js";
+
+// The pane's own bytes-out path, stubbed: the escape hatch only needs to know
+// the pool reaches the focused connection with them.
+const sent: { id: string; data: string }[] = [];
+const disposed: string[] = [];
+const mounts: { id: string; focus: boolean | undefined }[] = [];
+function fakeConn(kind: string, id: string) {
+  const el = document.createElement("div");
+  el.tabIndex = -1; // focusable via .focus(), like a real input/terminal
+  el.dataset.kind = kind;
+  el.dataset.session = id;
+  return {
+    sessionId: id,
+    kind,
+    el,
+    onMount(opts?: { focus?: boolean }) {
+      mounts.push({ id, focus: opts?.focus });
+    },
+    onUnmount() {},
+    focusTerminal() {},
+    sendInput(data: string) {
+      sent.push({ id, data });
+    },
+    dispose() {
+      disposed.push(`${kind}:${id}`);
+    },
+  };
+}
+vi.mock("./attach.js", () => ({
+  createAttachConnection: (id: string) => fakeConn("attach", id),
+}));
+vi.mock("./structured.js", () => ({
+  createStructuredConnection: (id: string) => fakeConn("structured", id),
+}));
 
 afterEach(() => {
   vi.unstubAllGlobals();
+  sent.length = 0;
+  disposed.length = 0;
+  mounts.length = 0;
 });
 
+/** Minimal fixture for the `CatalogState` a `CatalogStore` broadcasts. */
+function session(id: string, view?: "Terminal" | "Structured"): Session {
+  return {
+    id,
+    cwd: "/repo",
+    command: "claude",
+    env: {},
+    metadata: {},
+    status: "Running",
+    created_at: "2026-01-01T00:00:00Z",
+    view,
+  };
+}
+
+/** A `CatalogStore` an id can be pushed into on demand, mirroring
+ *  events.test.ts's own injectable-socket pattern. */
+class FakeCatalogSocket {
+  onmessage: ((ev: { data: string }) => void) | null = null;
+  onopen: (() => void) | null = null;
+  onclose: (() => void) | null = null;
+  onerror: (() => void) | null = null;
+  close(): void {}
+  push(sessions: Session[]): void {
+    this.onmessage?.({ data: JSON.stringify({ type: "Snapshot", sessions }) });
+  }
+}
+function fakeStore(): { store: CatalogStore; socket: FakeCatalogSocket } {
+  const socket = new FakeCatalogSocket();
+  const store = new CatalogStore({ socket: () => socket as unknown as WebSocket });
+  store.start();
+  return { store, socket };
+}
+
 const A = "aaaaaaaa-0000-0000-0000-0000000000ff";
 const B = "bbbbbbbb-0000-0000-0000-0000000000ff";
 
@@ -85,3 +157,226 @@ describe("ConnectionPool.setFocus", () => {
     await Promise.resolve();
   });
 });
+
+describe("ConnectionPool.sendToFocused", () => {
+  it("types the bytes into the focused session's PTY", () => {
+    mockFetch();
+    sent.length = 0;
+    const pool = new ConnectionPool();
+    const pane = document.createElement("div");
+    pool.mount(A, pane);
+    pool.setFocus(A);
+
+    expect(pool.sendToFocused("\x0b")).toBe(true);
+    expect(sent).toEqual([{ id: A, data: "\x0b" }]);
+  });
+
+  it("is a no-op with nothing focused", () => {
+    mockFetch();
+    sent.length = 0;
+    const pool = new ConnectionPool();
+
+    expect(pool.sendToFocused("\x0b")).toBe(false);
+    expect(sent).toEqual([]);
+  });
+});
+
+// A deep link or restored layout can `mount()` a session before the catalog
+// snapshot names its view — the daemon defaults an absent `view` to
+// `"Terminal"`, but so does an *unknown* session, and only one of those is
+// actually resolved (#140 review).
+describe("ConnectionPool: view resolution races", () => {
+  it("replaces a wrongly-typed connection once the catalog resolves it, without waiting for another mount()", () => {
+    mockFetch();
+    const { store, socket } = fakeStore();
+    const pool = new ConnectionPool({ store });
+    const pane = document.createElement("div");
+
+    pool.mount(A, pane); // no info: deep-link-before-snapshot race
+    expect(disposed).toEqual([]);
+
+    socket.push([session(A, "Structured")]);
+
+    expect(disposed).toEqual(["attach:" + A]);
+    // The fresh connection landed in the same pane nothing re-mounted it into.
+    expect(pane.children).toHaveLength(1);
+  });
+
+  it("also repairs a wrongly-typed connection that is parked, not mounted, without evicting its other parked siblings", () => {
+    mockFetch();
+    const { store, socket } = fakeStore();
+    const pool = new ConnectionPool({ store });
+    const hidden = document.body.lastElementChild as HTMLElement; // this pool's own cache
+    pool.mount(A, document.createElement("div"));
+    pool.mount(B, document.createElement("div"));
+    pool.unmount(A);
+    pool.unmount(B);
+    disposed.length = 0;
+
+    socket.push([session(A, "Structured")]);
+
+    expect(disposed).toEqual(["attach:" + A]);
+    // B's own element is still parked — A's repair didn't wipe its siblings
+    // out of the shared hidden cache.
+    expect(hidden.querySelector(`[data-session="${B}"]`)).not.toBeNull();
+    expect((hidden.querySelector(`[data-session="${A}"]`) as HTMLElement | null)?.dataset.kind).toBe("structured");
+  });
+
+  it("does not replace a connection whose resolved view already matches", () => {
+    mockFetch();
+    const { store, socket } = fakeStore();
+    const pool = new ConnectionPool({ store });
+    const pane = document.createElement("div");
+    pool.mount(A, pane, { name: "a", command: "claude", view: "Structured" });
+    disposed.length = 0;
+
+    socket.push([session(A, "Structured")]);
+
+    expect(disposed).toEqual([]);
+  });
+
+  it("does not downgrade an already-resolved connection when a later mount() call has no info", () => {
+    mockFetch();
+    const pool = new ConnectionPool();
+    const pane = document.createElement("div");
+    pool.mount(A, pane, { name: "a", command: "claude", view: "Structured" });
+    disposed.length = 0;
+
+    pool.mount(A, pane); // e.g. a re-render before the catalog answers again
+
+    expect(disposed).toEqual([]);
+  });
+
+  it("does not treat a session missing from the catalog as Terminal and churn a live connection", () => {
+    mockFetch();
+    const { store, socket } = fakeStore();
+    const pool = new ConnectionPool({ store });
+    const pane = document.createElement("div");
+    pool.mount(A, pane, { name: "a", command: "claude", view: "Structured" });
+    disposed.length = 0;
+
+    // `A` is absent from this snapshot — main.ts's own subscription handles
+    // closing the pane; the pool must not race it by "fixing" the view first.
+    socket.push([session(B, "Terminal")]);
+
+    expect(disposed).toEqual([]);
+  });
+
+  it("re-focuses the fresh connection when the keyboard was actually inside the replaced pane", () => {
+    mockFetch();
+    const { store, socket } = fakeStore();
+    const pool = new ConnectionPool({ store });
+    const pane = document.createElement("div");
+    document.body.appendChild(pane);
+    pool.mount(A, pane);
+    pool.setFocus(A);
+    (pane.firstElementChild as HTMLElement).focus();
+    expect(document.activeElement).toBe(pane.firstElementChild);
+    mounts.length = 0;
+
+    socket.push([session(A, "Structured")]);
+
+    expect(disposed).toEqual(["attach:" + A]);
+    expect(mounts).toEqual([{ id: A, focus: true }]);
+    pane.remove();
+  });
+
+  it("does not steal focus from a same-tab sidebar preview even though focusedId still names the previous pane", () => {
+    // docs/PREVIEW.md: previewing a session already open in the current tab
+    // moves the keyboard into the sidebar without ever calling setFocus, so
+    // `focusedId` keeps naming the pane the operator was in before — but the
+    // DOM disagrees, and the DOM is what must decide.
+    mockFetch();
+    const { store, socket } = fakeStore();
+    const pool = new ConnectionPool({ store });
+    const pane = document.createElement("div");
+    document.body.appendChild(pane);
+    pool.mount(A, pane);
+    pool.setFocus(A);
+    (pane.firstElementChild as HTMLElement).focus();
+
+    const sidebarInput = document.createElement("input");
+    document.body.appendChild(sidebarInput);
+    sidebarInput.focus();
+    expect(document.activeElement).toBe(sidebarInput);
+    mounts.length = 0;
+
+    socket.push([session(A, "Structured")]);
+
+    expect(disposed).toEqual(["attach:" + A]);
+    expect(mounts).toEqual([{ id: A, focus: false }]);
+    pane.remove();
+    sidebarInput.remove();
+  });
+
+  it("counts focus on a descendant of the pane's element, not just the element itself", () => {
+    mockFetch();
+    const { store, socket } = fakeStore();
+    const pool = new ConnectionPool({ store });
+    const pane = document.createElement("div");
+    document.body.appendChild(pane);
+    pool.mount(A, pane);
+    pool.setFocus(A);
+    const textarea = document.createElement("textarea");
+    (pane.firstElementChild as HTMLElement).appendChild(textarea);
+    textarea.focus();
+    expect(document.activeElement).toBe(textarea);
+    mounts.length = 0;
+
+    socket.push([session(A, "Structured")]);
+
+    expect(mounts).toEqual([{ id: A, focus: true }]);
+    pane.remove();
+  });
+
+  it("treats document.body (nothing meaningfully focused) as no active descendant", () => {
+    mockFetch();
+    const { store, socket } = fakeStore();
+    const pool = new ConnectionPool({ store });
+    const pane = document.createElement("div");
+    document.body.appendChild(pane);
+    pool.mount(A, pane);
+    pool.setFocus(A);
+    (document.activeElement as HTMLElement | null)?.blur();
+    expect(document.activeElement).toBe(document.body);
+    mounts.length = 0;
+
+    socket.push([session(A, "Structured")]);
+
+    expect(mounts).toEqual([{ id: A, focus: false }]);
+    pane.remove();
+  });
+
+  it("does not steal focus for a merely-visible pane that was never actually focused", () => {
+    mockFetch();
+    const { store, socket } = fakeStore();
+    const pool = new ConnectionPool({ store });
+    const paneA = document.createElement("div");
+    const paneB = document.createElement("div");
+    pool.mount(A, paneA);
+    pool.mount(B, paneB);
+    pool.setFocus(B); // B is the real keyboard focus; A is only visible
+    mounts.length = 0;
+
+    socket.push([session(A, "Structured")]);
+
+    expect(disposed).toEqual(["attach:" + A]);
+    expect(mounts).toEqual([{ id: A, focus: false }]);
+  });
+
+  it("does not focus a parked (unmounted) connection it repairs", () => {
+    mockFetch();
+    const { store, socket } = fakeStore();
+    const pool = new ConnectionPool({ store });
+    const pane = document.createElement("div");
+    pool.mount(A, pane);
+    pool.setFocus(A);
+    pool.unmount(A); // parked — no longer visible, `focusedId` still names it
+    mounts.length = 0;
+
+    socket.push([session(A, "Structured")]);
+
+    expect(disposed).toEqual(["attach:" + A]);
+    expect(mounts).toEqual([]); // parked repair calls onUnmount, never onMount
+  });
+});

web/src/connections.ts

@@ -1,10 +1,10 @@
-import {
-  createAttachConnection,
-  type AttachConnection,
-  type AttachInfo,
-} from "./attach.js";
+import { createAttachConnection } from "./attach.js";
+import type { AttachInfo } from "./paneTitle.js";
+import type { PaneConnection } from "./pane.js";
+import { createStructuredConnection } from "./structured.js";
 import { setSessionFocus } from "./api.js";
-import type { Uuid } from "./types.js";
+import type { CatalogState, CatalogStore } from "./events.js";
+import { sessionName, type SessionView, type Uuid } from "./types.js";
 
 /**
  * How many *parked* (off-screen but still-connected) sessions to keep warm
@@ -16,6 +16,15 @@ import type { Uuid } from "./types.js";
  */
 const MAX_PARKED = 6;
 
+/** A session's view defaults to `"Terminal"` wherever it isn't carried —
+ *  matching the wire default (`SessionView`'s `#[default]`, types.ts). Only
+ *  meaningful once the session itself is known; an altogether-unknown
+ *  session (no `AttachInfo`/`Session` at all) is a distinct, un-resolved
+ *  state callers must check for separately, not "Terminal". */
+function resolveView(view: SessionView | undefined): SessionView {
+  return view ?? "Terminal";
+}
+
 export interface PoolOptions {
   /** Fired when the focused session changes (drives sidebar highlight + HUD). */
   onFocusChange?: (id: Uuid | null) => void;
@@ -27,6 +36,9 @@ export interface PoolOptions {
   onClosed?: (id: Uuid) => void;
   /** Forwarded to each connection: should a dropped socket be retried? */
   shouldReconnect?: (id: Uuid, code: number) => boolean;
+  /** Threaded through to a structured connection so its rail can read live
+   *  worktree/git-status data (#140). Terminal connections don't need it. */
+  store?: CatalogStore;
 }
 
 /**
@@ -40,12 +52,19 @@ export interface PoolOptions {
  */
 export class ConnectionPool {
   /** All live connections. Insertion order doubles as LRU: oldest first. */
-  private readonly cache = new Map<Uuid, AttachConnection>();
+  private readonly cache = new Map<Uuid, PaneConnection>();
+  /** The view each cached connection was actually created for — a deep link
+   *  or a restored layout can `mount()` a session before the catalog
+   *  snapshot names its view, defaulting it to `"Terminal"`; this is what
+   *  lets a later reconciliation notice the resolved view disagrees (#140
+   *  review). */
+  private readonly connViews = new Map<Uuid, SessionView>();
   /** Sessions currently mounted into a visible pane (never evicted). */
   private readonly mounted = new Set<Uuid>();
   private readonly hidden: HTMLElement;
   private focusedId: Uuid | null = null;
   private readonly opts: PoolOptions;
+  private readonly unsubscribeStore?: () => void;
 
   constructor(opts: PoolOptions = {}) {
     this.opts = opts;
@@ -54,6 +73,11 @@ export class ConnectionPool {
     this.hidden.className = "conn-cache";
     this.hidden.setAttribute("aria-hidden", "true");
     document.body.appendChild(this.hidden);
+    // A session `mount()`ed before its catalog entry exists gets a
+    // `"Terminal"` connection by default; once the snapshot actually names
+    // the view, fix any connection that guessed wrong — nothing else
+    // re-`mount()`s an already-open pane just because the catalog updated.
+    this.unsubscribeStore = opts.store?.subscribe((state) => this.reconcileViews(state));
   }
 
   /** The focused session, or null when nothing is focused (welcome pane). */
@@ -74,33 +98,98 @@ export class ConnectionPool {
    * Ensure `id` is live and shown inside `pane`, reusing its connection if one
    * exists (refreshing LRU recency). Does not touch other mounted panes.
    */
-  mount(id: Uuid, pane: HTMLElement, info?: AttachInfo): void {
+  mount(id: Uuid, pane: HTMLElement, info?: AttachInfo, opts?: { focus?: boolean }): void {
     let conn = this.cache.get(id);
     if (conn) {
-      this.cache.delete(id);
-      this.cache.set(id, conn);
+      // `info === undefined` means "session not known yet", not "Terminal" —
+      // never downgrade a resolved connection just because a later caller
+      // couldn't resolve the session. Only a *resolved* view that disagrees
+      // with what this connection was built for forces a replace.
+      if (info !== undefined && resolveView(info.view) !== this.connViews.get(id)) {
+        conn = this.replace(id, info);
+      } else {
+        this.cache.delete(id);
+        this.cache.set(id, conn); // LRU refresh
+      }
     } else {
-      conn = createAttachConnection(
-        id,
-        {
-          onRequestClose: (sid) => this.opts.onRequestClose?.(sid),
-          onClosed: (sid) => this.opts.onClosed?.(sid),
-          shouldReconnect: (sid, code) => this.opts.shouldReconnect?.(sid, code) ?? false,
-        },
-        info,
-      );
+      conn = this.create(id, info);
       this.cache.set(id, conn);
     }
     if (conn.el.parentElement !== pane) {
       pane.replaceChildren(conn.el);
-      conn.onMount();
+      conn.onMount(opts);
     } else if (!this.mounted.has(id)) {
-      conn.onMount();
+      conn.onMount(opts);
     }
     this.mounted.add(id);
     this.evict();
   }
 
+  private create(id: Uuid, info?: AttachInfo): PaneConnection {
+    const view = resolveView(info?.view);
+    this.connViews.set(id, view);
+    const connOpts = {
+      onRequestClose: (sid: Uuid) => this.opts.onRequestClose?.(sid),
+      onClosed: (sid: Uuid) => this.opts.onClosed?.(sid),
+      shouldReconnect: (sid: Uuid, code: number) => this.opts.shouldReconnect?.(sid, code) ?? false,
+    };
+    return view === "Structured"
+      ? createStructuredConnection(id, connOpts, info, this.opts.store)
+      : createAttachConnection(id, connOpts, info);
+  }
+
+  /** Dispose whatever is cached for `id` and cache a freshly created
+   *  connection in its place. Does not touch the DOM or `mounted` — callers
+   *  place the new element themselves. */
+  private replace(id: Uuid, info?: AttachInfo): PaneConnection {
+    this.cache.get(id)?.dispose();
+    const fresh = this.create(id, info);
+    this.cache.set(id, fresh);
+    return fresh;
+  }
+
+  /** Proactively fix any cached connection whose view no longer matches the
+   *  catalog — the only path that repairs a pane nothing will `mount()`
+   *  again on its own (parked, or mounted but not currently being
+   *  re-rendered by anything else). A session absent from `state` (not yet
+   *  known, or removed) is left alone — that's `main.ts`'s
+   *  `closePane`/eviction concern, not a view mismatch. */
+  private reconcileViews(state: CatalogState): void {
+    for (const id of [...this.cache.keys()]) {
+      const session = state.sessions.get(id);
+      if (session === undefined || resolveView(session.view) === this.connViews.get(id)) continue;
+      const existing = this.cache.get(id)!;
+      const parent = existing.el.parentElement;
+      const wasMounted = this.mounted.has(id);
+      // Capture before anything below touches the DOM: dispose()/el.remove()
+      // detach `existing.el`, and once a focused descendant is detached the
+      // browser moves `document.activeElement` to `<body>` — too late to
+      // tell whether the keyboard was actually in this pane.
+      const hadDomFocus = existing.el.contains(document.activeElement);
+      const info: AttachInfo = { name: sessionName(session), command: session.command, view: session.view };
+      const fresh = this.replace(id, info);
+      existing.el.remove(); // don't rely on dispose() to clear the DOM
+      if (parent && parent !== this.hidden) {
+        parent.replaceChildren(fresh.el);
+      } else {
+        // Parked: `this.hidden` holds every parked connection's element as
+        // siblings — append, never replaceChildren, or they'd all vanish.
+        this.hidden.appendChild(fresh.el);
+      }
+      if (wasMounted) {
+        // `focusedId` names the session the pool was last told to focus —
+        // but a same-tab sidebar preview moves the keyboard into the
+        // sidebar without clearing it (multiview.ts skips `setFocus` while
+        // previewing), so `focusedId` alone can point at a pane the
+        // keyboard already left. Only re-focus when the DOM agrees it
+        // never did.
+        fresh.onMount({ focus: this.focusedId === id && hadDomFocus });
+      } else {
+        fresh.onUnmount();
+      }
+    }
+  }
+
   /** Park `id` back into the hidden cache (still connected) and stop showing it. */
   unmount(id: Uuid): void {
     if (!this.mounted.delete(id)) return;
@@ -114,13 +203,17 @@ export class ConnectionPool {
   /**
    * Reconcile the visible set to exactly `entries` (in render order): park any
    * mounted session not listed, mount/refresh each listed one in its pane.
+   * `focus: false` shows the panes without taking the keyboard (preview).
    */
-  setVisible(entries: { id: Uuid; pane: HTMLElement; info?: AttachInfo }[]): void {
+  setVisible(
+    entries: { id: Uuid; pane: HTMLElement; info?: AttachInfo }[],
+    opts?: { focus?: boolean },
+  ): void {
     const next = new Set(entries.map((e) => e.id));
     for (const id of [...this.mounted]) {
       if (!next.has(id)) this.unmount(id);
     }
-    for (const e of entries) this.mount(e.id, e.pane, e.info);
+    for (const e of entries) this.mount(e.id, e.pane, e.info, opts);
   }
 
   /** Also tells the daemon which pane is focused (docs/SIDEBAR.md's
@@ -155,19 +248,34 @@ export class ConnectionPool {
     this.cache.get(this.focusedId)?.focusTerminal();
   }
 
+  /** Type raw bytes into the focused session's PTY. Returns false when there is
+   *  nothing focused, or its connection is gone — the leader's literal Ctrl-K
+   *  is a no-op over the welcome pane rather than an error
+   *  (docs/COMMAND-BAR.md). */
+  sendToFocused(data: string): boolean {
+    if (this.focusedId === null) return false;
+    const conn = this.cache.get(this.focusedId);
+    if (!conn) return false;
+    conn.sendInput(data);
+    return true;
+  }
+
   /** Fully disconnect + forget a session. */
   close(id: Uuid): void {
     const conn = this.cache.get(id);
     if (!conn) return;
     conn.dispose();
     this.cache.delete(id);
+    this.connViews.delete(id);
     this.mounted.delete(id);
     if (this.focusedId === id) this.setFocus(null);
   }
 
   dispose(): void {
+    this.unsubscribeStore?.();
     for (const conn of this.cache.values()) conn.dispose();
     this.cache.clear();
+    this.connViews.clear();
     this.mounted.clear();
     this.hidden.remove();
   }

web/src/debug.ts

@@ -2,6 +2,8 @@
 // survives reloads, flipped by a keybind (Ctrl+Shift+D), and force-enabled by
 // `?hud` in dev. A `maestro-hud-toggle` event lets the HUD re-render on change.
 
+import { CommandSet, defineCommands } from "./commands.js";
+
 const STORAGE_KEY = "maestro:hud";
 export const HUD_TOGGLE_EVENT = "maestro-hud-toggle";
 
@@ -31,12 +33,9 @@ export function toggleHud(): void {
   setHudEnabled(!isHudEnabled());
 }
 
+const hudKeys = new CommandSet(defineCommands({ "debug.toggleHud": () => toggleHud() }));
+
 /** Global keybind: Ctrl+Shift+D toggles the debug HUD. */
 export function installHudKeybind(): void {
-  window.addEventListener("keydown", (e) => {
-    if (e.ctrlKey && e.shiftKey && (e.key === "D" || e.key === "d")) {
-      e.preventDefault();
-      toggleHud();
-    }
-  });
+  window.addEventListener("keydown", (e) => hudKeys.handle(e));
 }

web/src/fastForward.test.ts

@@ -34,12 +34,14 @@ describe("resolveFastForward (#67)", () => {
     const res = resolveFastForward(projects, presets, "amber-falcon");
     expect(res.project?.path).toBe("/repos/fresh");
     expect(res.command).toBe("aider");
-    expect(res.name).toBe("amber-falcon");
+    expect(res.handle).toBe("amber-falcon");
 
     const req = buildFastForwardRequest(res)!;
     expect(req.cwd).toBe("/repos/fresh");
     expect(req.command).toBe("aider");
-    expect(req.metadata).toEqual({ name: "amber-falcon" });
+    // No name (#131): the daemon names the session after its first prompt,
+    // and a name here would collide with the branch handle.
+    expect(req.metadata).toBeUndefined();
     expect(req.worktree).toEqual({
       base_repo: "/repos/fresh",
       branch: "amber-falcon",
@@ -88,9 +90,9 @@ describe("resolveFastForward (#67)", () => {
     expect(buildFastForwardRequest(res)).toBeNull();
   });
 
-  it("downgrades to a draft when the generated name is missing", () => {
+  it("downgrades to a draft when the generated handle is missing", () => {
     const res = resolveFastForward([project({ last_command: "claude" })], presets);
-    expect(res.name).toBeUndefined();
+    expect(res.handle).toBeUndefined();
     expect(buildFastForwardRequest(res)).toBeNull();
   });
 
@@ -108,6 +110,17 @@ describe("resolveFastForward (#67)", () => {
     });
   });
 
+  it("seeds the handle as the branch and leaves the name field empty (#131)", () => {
+    const res = resolveFastForward(
+      [project({ path: "/repos/p", base_repo: "/repos/p", last_command: "aider" })],
+      presets,
+      "amber-falcon",
+    );
+    const seed = fastForwardSeed(res);
+    expect(seed.name).toBe("");
+    expect(seed.worktreeBranch).toBe("amber-falcon");
+  });
+
   it("leaves the worktree default alone when not even a project resolved", () => {
     // Not `false`: the form defaults the toggle on and a false would stick,
     // so the fallback draft would disagree with a normally-opened draft and

web/src/fastForward.ts

@@ -10,19 +10,21 @@ import { sortProjects } from "./projectList.js";
 export interface FastForwardResolution {
   project?: Project;
   command?: string;
-  name?: string;
+  /** A generated handle for the worktree branch (#131). Not a session name:
+   *  the fast path names no session. */
+  handle?: string;
 }
 
 /** The defaults: the currently focused session's project when it's still a
  *  known project, else the most recent one (fresh-first, same ordering the
  *  picker shows) — so `N` lands where the operator currently is, matching
  *  what plain `n` seeds from `spawnSimilarProjectSeed`. Its last command
- *  falls back to the first non-custom preset, and the name is freshly
- *  generated when the daemon supplied one. */
+ *  falls back to the first non-custom preset, and the branch handle is
+ *  freshly generated when the daemon supplied one. */
 export function resolveFastForward(
   projects: Project[],
   presets: SpawnPreset[],
-  name?: string,
+  handle?: string,
   focusedCwd?: string,
 ): FastForwardResolution {
   const project =
@@ -30,41 +32,45 @@ export function resolveFastForward(
   const lastCommand = project?.last_command?.trim();
   const command =
     lastCommand || presets.find((p) => p.command !== "")?.command || undefined;
-  return { project, command, name: name || undefined };
+  return { project, command, handle: handle || undefined };
 }
 
 /** The immediate spawn request — worktree on, new branch named after the
- *  generated session name — or `null` when any default is missing. */
+ *  generated handle — or `null` when any default is missing.
+ *
+ *  The request carries no name (#131): the daemon assigns a provisional one
+ *  and replaces it once the session sees its first prompt. A name here would
+ *  also collide with the branch handle's own session. */
 export function buildFastForwardRequest(
   res: FastForwardResolution,
 ): CreateSessionRequest | null {
-  const { project, command, name } = res;
-  if (!project || !command?.trim() || !name) return null;
+  const { project, command, handle } = res;
+  if (!project || !command?.trim() || !handle) return null;
   return {
     cwd: project.path,
     command,
-    metadata: { name },
     worktree: {
       base_repo: project.base_repo ?? project.path,
-      branch: name,
+      branch: handle,
       create_branch: true,
     },
   };
 }
 
 /** Seed for the fallback spawn form: whatever did resolve goes into the
- *  form; the rest stays with its own defaults. */
+ *  form; the rest stays with its own defaults. The name field stays empty
+ *  (#131) — the handle seeds the branch, not the session name. */
 export function fastForwardSeed(res: FastForwardResolution) {
   return {
     cwd: res.project?.path ?? "",
     command: res.command ?? "",
-    name: res.name ?? "",
+    name: "",
     // Left undefined rather than false when nothing resolved: the form
     // defaults the toggle on, and `false` would stick, so the fallback form
     // would disagree with both a normally-opened form and the TUI's fast path
     // (#67 review).
     worktreeEnabled: res.project ? true : undefined,
     worktreeBranch:
-      res.project && res.name ? res.name : undefined,
+      res.project && res.handle ? res.handle : undefined,
   };
 }

web/src/help.test.ts

@@ -1,14 +1,8 @@
 // @vitest-environment happy-dom
 import { afterEach, beforeEach, describe, expect, it } from "vitest";
 
-import {
-  SHORTCUTS,
-  closeHelp,
-  installHelpKeybind,
-  isHelpOpen,
-  isTypingTarget,
-  openHelp,
-} from "./help.js";
+import { defineCommands, keyCaps, publishCommands, publishedCommands } from "./commands.js";
+import { closeHelp, groupedCommands, installHelpKeybind, isHelpOpen, openHelp } from "./help.js";
 
 beforeEach(() => {
   installHelpKeybind();
@@ -30,14 +24,51 @@ function rows(): string[] {
 }
 
 describe("help overlay", () => {
-  it("renders every registered shortcut, grouped", () => {
+  it("renders exactly the commands the registry has bound, grouped", () => {
     openHelp();
-    const groups = [...document.querySelectorAll(".help-group-title")].map((h) => h.textContent);
-    expect(groups).toEqual(SHORTCUTS.map((g) => g.title));
-    expect(rows()).toEqual(SHORTCUTS.flatMap((g) => g.items.map((s) => s.keys.join(" "))));
-    expect(document.querySelectorAll(".help-desc")).toHaveLength(
-      SHORTCUTS.reduce((n, g) => n + g.items.length, 0),
+    const groups = groupedCommands();
+    expect([...document.querySelectorAll(".help-group-title")].map((h) => h.textContent)).toEqual(
+      groups.map((g) => g.title),
     );
+    expect(rows()).toEqual(
+      groups.flatMap((g) => g.items.map((c) => keyCaps(c.keys[0]).join(" "))),
+    );
+    expect([...document.querySelectorAll(".help-desc")].map((d) => d.textContent)).toEqual(
+      groups.flatMap((g) => g.items.map((c) => c.label)),
+    );
+  });
+
+  it("names each row by its command id, so a row can't drift from its command", () => {
+    openHelp();
+    expect([...document.querySelectorAll<HTMLElement>(".help-row")].map((r) => r.dataset.commandId))
+      .toEqual(publishedCommands().map((c) => c.id));
+  });
+
+  // #159: the leader comes from the daemon, so the overlay must render the
+  // configured chord — a hardcoded `Ctrl A` is the visible half of the bug.
+  it("renders the configured leader's chord, not a hardcoded Ctrl A", () => {
+    const bound = defineCommands(
+      { "pane.literalCtrlK": () => {}, "pane.literalLeader": () => {} },
+      "ctrl-b",
+    );
+    publishCommands(bound);
+    try {
+      openHelp();
+      const keysOf = (id: string) =>
+        [
+          ...(document.querySelector(`.help-row[data-command-id="${id}"]`) as HTMLElement)
+            .querySelectorAll("kbd"),
+        ]
+          .map((k) => k.textContent)
+          .join(" ");
+      expect(keysOf("pane.literalCtrlK")).toBe("Ctrl B then Ctrl K");
+      expect(keysOf("pane.literalLeader")).toBe("Ctrl B then Ctrl B");
+    } finally {
+      // Leave the registry as the rest of the suite expects it.
+      publishCommands(
+        defineCommands({ "pane.literalCtrlK": () => {}, "pane.literalLeader": () => {} }),
+      );
+    }
   });
 
   it("opens on ? and closes on a second ?", () => {
@@ -94,19 +125,3 @@ describe("help overlay", () => {
     expect(document.querySelectorAll(".help-overlay")).toHaveLength(1);
   });
 });
-
-describe("isTypingTarget", () => {
-  it("is true for form fields and editable nodes, false otherwise", () => {
-    const el = (html: string) => {
-      const d = document.createElement("div");
-      d.innerHTML = html;
-      return d.firstElementChild as HTMLElement;
-    };
-    expect(isTypingTarget(el("<input>"))).toBe(true);
-    expect(isTypingTarget(el("<textarea></textarea>"))).toBe(true);
-    expect(isTypingTarget(el("<select></select>"))).toBe(true);
-    expect(isTypingTarget(el('<div contenteditable="true"></div>'))).toBe(true);
-    expect(isTypingTarget(el("<button></button>"))).toBe(false);
-    expect(isTypingTarget(null)).toBe(false);
-  });
-});

web/src/help.ts

@@ -1,66 +1,15 @@
 /** Keyboard-shortcut overlay (`?`), the web counterpart of the TUI's help
- *  overlay. One registry drives both the rendering and what we claim is bound,
- *  so a binding added to `main.ts` without an entry here reads as missing. */
+ *  overlay. It renders the command registry (`commands.ts`) — the same list
+ *  that dispatches the keys — so a binding can never be documented as one
+ *  thing and do another. */
 
-export interface Shortcut {
-  /** Keycaps, rendered left to right as separate <kbd>. */
-  keys: string[];
-  description: string;
-}
-
-export interface ShortcutGroup {
-  title: string;
-  items: Shortcut[];
-}
-
-export const SHORTCUTS: ShortcutGroup[] = [
-  {
-    title: "Sessions",
-    items: [
-      { keys: ["n"], description: "Open the spawn form" },
-      { keys: ["N"], description: "Spawn a session with every default resolved" },
-    ],
-  },
-  {
-    title: "Session list",
-    items: [
-      {
-        keys: ["Ctrl", "Shift", "H"],
-        description: "Move the keyboard between the session list and the pane",
-      },
-      { keys: ["j"], description: "Highlight the next session" },
-      { keys: ["k"], description: "Highlight the previous session" },
-      { keys: ["Enter"], description: "Open the highlighted session, or expand a folder" },
-      { keys: ["Tab"], description: "Send the keyboard to the pane" },
-      { keys: ["Esc"], description: "Hand the keyboard back to the session list, from the pane" },
-    ],
-  },
-  {
-    title: "Help",
-    items: [
-      { keys: ["?"], description: "Show or hide this help" },
-      { keys: ["Esc"], description: "Close the help overlay or an open menu" },
-    ],
-  },
-  {
-    title: "Debug",
-    items: [{ keys: ["Ctrl", "Shift", "D"], description: "Toggle the debug HUD" }],
-  },
-];
-
-/** True when the event target swallows plain keystrokes — a form field, or the
- *  hidden textarea xterm types into. Shared with `main.ts` so every global
- *  single-key binding is deaf in the same places. */
-export function isTypingTarget(target: EventTarget | null): boolean {
-  const el = target as HTMLElement | null;
-  if (!el || typeof el.tagName !== "string") return false;
-  return (
-    el.tagName === "INPUT" ||
-    el.tagName === "TEXTAREA" ||
-    el.tagName === "SELECT" ||
-    el.isContentEditable
-  );
-}
+import {
+  CommandSet,
+  defineCommands,
+  keyCaps,
+  publishedCommands,
+  type Command,
+} from "./commands.js";
 
 let open: { el: HTMLElement; dispose: () => void } | null = null;
 
@@ -105,7 +54,7 @@ export function openHelp(): HTMLElement {
   head.append(title, close);
   panel.appendChild(head);
 
-  for (const group of SHORTCUTS) {
+  for (const group of groupedCommands()) {
     const section = document.createElement("section");
     section.className = "help-group";
     const heading = document.createElement("h3");
@@ -113,19 +62,20 @@ export function openHelp(): HTMLElement {
     heading.textContent = group.title;
     const list = document.createElement("dl");
     list.className = "help-list";
-    for (const item of group.items) {
+    for (const cmd of group.items) {
       const row = document.createElement("div");
       row.className = "help-row";
+      row.dataset.commandId = cmd.id;
       const keys = document.createElement("dt");
       keys.className = "help-keys";
-      for (const key of item.keys) {
+      for (const key of keyCaps(cmd.keys[0])) {
         const cap = document.createElement("kbd");
         cap.textContent = key;
         keys.appendChild(cap);
       }
       const desc = document.createElement("dd");
       desc.className = "help-desc";
-      desc.textContent = item.description;
+      desc.textContent = cmd.label;
       row.append(keys, desc);
       list.appendChild(row);
     }
@@ -150,6 +100,26 @@ export function openHelp(): HTMLElement {
   return el;
 }
 
+/** The registry's commands, in registry order, bucketed into the help
+ *  overlay's sections. Groups appear in the order their first command does. */
+export function groupedCommands(): { title: string; items: Command[] }[] {
+  const groups: { title: string; items: Command[] }[] = [];
+  for (const cmd of publishedCommands()) {
+    let group = groups.find((g) => g.title === cmd.group);
+    if (!group) {
+      group = { title: cmd.group, items: [] };
+      groups.push(group);
+    }
+    group.items.push(cmd);
+  }
+  return groups;
+}
+
+// The overlay's own two commands. `help.close` is `overlay`-scoped: it is only
+// fed keys while the dialog is up.
+const helpKeys = new CommandSet(defineCommands({ "help.toggle": () => toggleHelp() }));
+const overlayKeys = new CommandSet(defineCommands({ "help.close": () => closeHelp() }));
+
 let installed = false;
 
 /** Global keybind: `?` toggles the overlay, Escape closes it. Idempotent, so a
@@ -158,16 +128,7 @@ export function installHelpKeybind(): void {
   if (installed) return;
   installed = true;
   window.addEventListener("keydown", (e) => {
-    if (e.key === "Escape" && open) {
-      e.preventDefault();
-      closeHelp();
-      return;
-    }
-    // Shift is how `?` is typed on most layouts; the others would be a
-    // different binding entirely.
-    if (e.key !== "?" || e.ctrlKey || e.altKey || e.metaKey) return;
-    if (isTypingTarget(e.target)) return;
-    e.preventDefault();
-    toggleHelp();
+    if (open && overlayKeys.handle(e)) return;
+    helpKeys.handle(e);
   });
 }

web/src/killDialog.test.ts

@@ -0,0 +1,33 @@
+// @vitest-environment happy-dom
+import { beforeEach, describe, expect, it } from "vitest";
+import {
+  closeForceKillDialog,
+  openForceKillDialog,
+  openKillConfirmDialog,
+} from "./killDialog.js";
+
+describe("kill dialogs", () => {
+  beforeEach(() => {
+    closeForceKillDialog();
+    document.body.innerHTML = "";
+  });
+
+  it("focuses the kill button, so Enter confirms", () => {
+    const el = openKillConfirmDialog({
+      name: "alpha",
+      blockers: null,
+      onKill: () => Promise.resolve(),
+    });
+    expect(document.activeElement).toBe(el.querySelector(".kill-dialog-kill"));
+  });
+
+  it("focuses the force button too", () => {
+    const el = openForceKillDialog({
+      name: "alpha",
+      blockers: null,
+      reason: "worktree is dirty.",
+      onForce: () => Promise.resolve(),
+    });
+    expect(document.activeElement).toBe(el.querySelector(".kill-dialog-force"));
+  });
+});

web/src/killDialog.ts

@@ -1,14 +1,44 @@
 /**
- * Forced-kill prompt (#81).
+ * The two kill prompts (#81, #160).
  *
- * The daemon refuses to kill a session whose worktree still holds uncommitted
- * or unpushed work. `confirm()` can only ask the same question twice, so the
- * refusal gets its own dialog: it names what is in the way and offers the
- * override the daemon's `force=true` already implements. A kill the daemon
- * accepts never reaches here — there is nothing to warn about.
+ * A kill is destructive and unattended agents live in these sessions, so both
+ * clients ask before one goes through — the TUI's `KillConfirm`, and
+ * `openKillConfirmDialog` here (#160). Where the session's worktree still
+ * holds uncommitted or unpushed work, the confirmation says so up front, the
+ * same way the TUI's does.
+ *
+ * The daemon decides the rest: it refuses a kill over such a worktree, and
+ * that refusal needs an answer the confirmation cannot give — a forced kill.
+ * `openForceKillDialog` is that second prompt. A kill the daemon accepts never
+ * reaches it.
  */
 import { formatInTheWay, type InTheWay } from "./types.js";
 
+/** What both prompts need: a target to name and a button that acts on it. */
+interface KillDialogSpec {
+  /** Session name, as the sidebar shows it. */
+  name: string;
+  /** Sentence under the title. */
+  body: string;
+  /** Label on the acting button. */
+  confirmLabel: string;
+  /** Extra class on the acting button, so tests and styles can find it. */
+  confirmClass: string;
+  /** Run it. A rejection is rendered in the dialog, which stays open so the
+   *  press can be retried. */
+  onConfirm: () => Promise<void>;
+}
+
+export interface KillConfirmPrompt {
+  name: string;
+  /** What the card last saw in the way, when anything was. Shown before the
+   *  attempt, so "this will be refused" is not a surprise. */
+  blockers: InTheWay | null;
+  /** Run the plain kill. Opening a further dialog from here is allowed: the
+   *  confirmation only closes itself if it is still the one on screen. */
+  onKill: () => Promise<void>;
+}
+
 export interface ForceKillPrompt {
   /** Session name, as the sidebar shows it. */
   name: string;
@@ -30,9 +60,9 @@ export function closeForceKillDialog(): void {
   open = null;
 }
 
-/** Mount the prompt. Opening while one is up replaces it, so a second refusal
- *  can never stack two dialogs. */
-export function openForceKillDialog(p: ForceKillPrompt): HTMLElement {
+/** Mount one of the prompts. Opening while one is up replaces it, so the
+ *  confirmation and a refusal that follows it can never stack. */
+function mount(p: KillDialogSpec): HTMLElement {
   closeForceKillDialog();
 
   const el = document.createElement("div");
@@ -50,9 +80,7 @@ export function openForceKillDialog(p: ForceKillPrompt): HTMLElement {
 
   const body = document.createElement("p");
   body.className = "kill-dialog-body";
-  body.textContent = p.blockers
-    ? `Its worktree still has ${formatInTheWay(p.blockers)}. Forcing the kill removes the session and leaves the worktree on disk.`
-    : `${p.reason} Forcing the kill removes the session and leaves the worktree on disk.`;
+  body.textContent = p.body;
 
   const error = document.createElement("p");
   error.className = "kill-dialog-error";
@@ -65,22 +93,27 @@ export function openForceKillDialog(p: ForceKillPrompt): HTMLElement {
   cancel.className = "btn btn-ghost kill-dialog-cancel";
   cancel.textContent = "Cancel";
   cancel.addEventListener("click", closeForceKillDialog);
-  const force = document.createElement("button");
-  force.type = "button";
-  force.className = "btn btn-danger kill-dialog-force";
-  force.textContent = "Force kill";
-  force.addEventListener("click", () => {
-    force.disabled = true;
+  const confirm = document.createElement("button");
+  confirm.type = "button";
+  confirm.className = `btn btn-danger ${p.confirmClass}`;
+  confirm.textContent = p.confirmLabel;
+  confirm.addEventListener("click", () => {
+    confirm.disabled = true;
     void p
-      .onForce()
-      .then(closeForceKillDialog)
+      .onConfirm()
+      .then(() => {
+        // A handler that opened the refusal prompt has already replaced this
+        // dialog; closing here would take that one down with it.
+        if (open?.el === el) closeForceKillDialog();
+      })
       .catch((e: unknown) => {
-        force.disabled = false;
+        if (open?.el !== el) return;
+        confirm.disabled = false;
         error.hidden = false;
         error.textContent = `Failed to kill: ${(e as Error).message}`;
       });
   });
-  actions.append(cancel, force);
+  actions.append(cancel, confirm);
 
   panel.append(title, body, error, actions);
 
@@ -99,6 +132,34 @@ export function openForceKillDialog(p: ForceKillPrompt): HTMLElement {
   };
   window.addEventListener("keydown", onKeydown, true);
   open = { el, onKeydown };
-  cancel.focus();
+  // The acting button takes the focus in both prompts: the operator already
+  // asked for the kill, so Enter confirms it. Escape and the scrim cancel.
+  confirm.focus();
   return el;
 }
+
+/** Ask before a kill the daemon has not seen yet (#160). */
+export function openKillConfirmDialog(p: KillConfirmPrompt): HTMLElement {
+  return mount({
+    name: p.name,
+    body: p.blockers
+      ? `Its worktree still has ${formatInTheWay(p.blockers)}. The kill will be refused unless it is forced.`
+      : "The session and everything running in it go away. Its worktree stays on disk.",
+    confirmLabel: "Kill",
+    confirmClass: "kill-dialog-kill",
+    onConfirm: p.onKill,
+  });
+}
+
+/** Offer the override after the daemon refuses a guarded kill (#81). */
+export function openForceKillDialog(p: ForceKillPrompt): HTMLElement {
+  return mount({
+    name: p.name,
+    body: p.blockers
+      ? `Its worktree still has ${formatInTheWay(p.blockers)}. Forcing the kill removes the session and leaves the worktree on disk.`
+      : `${p.reason} Forcing the kill removes the session and leaves the worktree on disk.`,
+    confirmLabel: "Force kill",
+    confirmClass: "kill-dialog-force",
+    onConfirm: p.onForce,
+  });
+}

web/src/kit.ts

@@ -129,6 +129,7 @@ export function renderKit(): HTMLElement {
       "--muted",
       "--faint",
       "--accent",
+      "--preview",
       "--danger",
       "--warn",
     ];

web/src/layout.test.ts

@@ -2,6 +2,7 @@ import { describe, expect, it } from "vitest";
 
 import {
   emptyLayout,
+  equalizeRatios,
   leaves,
   locateSession,
   openSessions,
@@ -44,6 +45,23 @@ describe("splitLeaf", () => {
   });
 });
 
+describe("equalizeRatios", () => {
+  it("resets nested splits to equal width, not just the newest one", () => {
+    const tab = tabWithOneLeaf("s1");
+    const first = leaves(tab.root)[0].id;
+    splitLeaf(tab, first, "s2", "row", true); // A|B, 0.5/0.5
+    const second = leaves(tab.root)[1].id;
+    splitLeaf(tab, second, "s3", "row", true); // A(0.5) | (B|C, 0.5/0.5) -> B,C at 0.25 each
+
+    equalizeRatios(tab.root);
+
+    const root = tab.root as Extract<typeof tab.root, { kind: "split" }>;
+    expect(root.ratio).toBeCloseTo(1 / 3);
+    const inner = root.b as Extract<typeof root.b, { kind: "split" }>;
+    expect(inner.ratio).toBeCloseTo(1 / 2);
+  });
+});
+
 describe("removeLeaf", () => {
   it("collapses the parent split into the surviving sibling", () => {
     const tab = tabWithOneLeaf("s1");

web/src/layout.ts

@@ -118,6 +118,17 @@ export function removeLeaf(tab: Tab, leafId: string): void {
   tab.root = tab.root ? rec(tab.root) : null;
 }
 
+/** Reset every split ratio under `node` so all leaves get equal width,
+ *  regardless of split direction or nesting order. Returns the leaf count. */
+export function equalizeRatios(node: Node | null): number {
+  if (!node) return 0;
+  if (node.kind === "leaf") return 1;
+  const na = equalizeRatios(node.a);
+  const nb = equalizeRatios(node.b);
+  node.ratio = na / (na + nb);
+  return na + nb;
+}
+
 export function addTab(layout: Layout): Tab {
   const tab: Tab = {
     id: freshId("t"),

web/src/main.ts

@@ -6,7 +6,9 @@ import { renderSidebar } from "./catalog.js";
 import { ConnectionPool } from "./connections.js";
 import { installDrawer, installDrawerSwipe, requestToggleDrawer } from "./drawer.js";
 import { installHudKeybind } from "./debug.js";
-import { installHelpKeybind, isHelpOpen, isTypingTarget } from "./help.js";
+import { installHelpKeybind, isHelpOpen } from "./help.js";
+import { CommandSet, DEFAULT_LEADER, controlByte, defineCommands, isBarTypingTarget } from "./commands.js";
+import { isCommandBarOpen, openCommandBar, SPAWN_DIRECTORY_EVENT } from "./commandBar.js";
 import { DaemonLink } from "./daemonLink.js";
 import { CatalogStore } from "./events.js";
 import { installRestartOverlay } from "./restartOverlay.js";
@@ -15,6 +17,7 @@ import {
   createSession,
   fetchNames,
   getDaemonInfo,
+  gitRoot,
   projects as fetchProjects,
 } from "./api.js";
 import {
@@ -29,9 +32,10 @@ import { mountHud, type Hud } from "./hud.js";
 import { emptyLayout, type Layout, openSessions } from "./layout.js";
 import { createMultiView, type MultiView } from "./multiview.js";
 import { loadLayout, saveLayout } from "./persistence.js";
+import { createPreviewSchedule } from "./previewSchedule.js";
 import {
   FOCUS_PANE_EVENT,
-  FOCUS_SIDEBAR_EVENT,
+  OPEN_COMMAND_BAR_EVENT,
   OPEN_SPAWN_EVENT,
   SESSION_SELECT_EVENT,
   SPAWN_SIMILAR_EVENT,
@@ -78,6 +82,21 @@ async function bootApp(): Promise<void> {
 
 const store = new CatalogStore();
 
+// The daemon's home dir, for the command bar's `~/…` directory abbreviation.
+// Absolute paths are a fine fallback until it lands.
+let homeDir: string | undefined;
+void getDaemonInfo()
+  .then((info) => {
+    homeDir = info.home_dir;
+    // The leader is the operator's, not this module's (#159): a daemon that
+    // names one rebinds the chords hanging off it, and the `?` overlay and the
+    // command bar re-render from the rebuilt set.
+    if (info.leader) useLeader(info.leader);
+  })
+  .catch(() => {
+    /* absolute paths and the default leader are fine fallbacks */
+  });
+
 // The daemon's identity and liveness: names the release in the sidebar's status
 // dot, and blocks the UI behind the restart overlay while the daemon is away
 // (docs/RESTART.md). The events socket is the trigger — it dies first.
@@ -104,9 +123,20 @@ shellEl.dataset.route = "catalog";
 // after the welcome renderer). The hook only fires on user interaction, by which
 // point `mv` is assigned.
 let mv: MultiView;
+
+// Preview timing (docs/PREVIEW.md): the first move shows at once, and a burst
+// — j held down, or the pointer sweeping the whole list — is coalesced so it
+// costs a couple of pane mounts instead of one per row walked.
+const schedulePreview = createPreviewSchedule((sessionId) => {
+  ensureMultiView();
+  mv?.previewSession(sessionId);
+  updateShellRoute();
+});
+
 const sidebar = renderSidebar(store, {
   onLeafDrag: (id, e) => mv?.beginSessionDrag(id, e),
   link,
+  onPreview: schedulePreview,
 });
 const content = document.createElement("section");
 content.className = "content";
@@ -142,6 +172,7 @@ const pool = new ConnectionPool({
   onRequestClose: (id) => closePane(id),
   onClosed: (id) => closePane(id),
   shouldReconnect: (id, code) => shouldRetryClose(id, code, store.snapshot().sessions),
+  store,
 });
 
 // Session death used to reach the UI on two uncoordinated channels — the row
@@ -179,12 +210,14 @@ function scheduleSave(): void {
 
 function infoFor(sessionId: string) {
   const s = store.snapshot().sessions.get(sessionId);
-  return s ? { name: sessionName(s), command: s.command } : undefined;
+  return s ? { name: sessionName(s), command: s.command, view: s.view } : undefined;
 }
 
 /** Drive the shell's responsive layout off whether any pane is open. */
 function updateShellRoute(): void {
-  const hasPanes = openSessions(layout).size > 0;
+  // A preview is not an open pane (docs/PREVIEW.md), so the mobile shell does
+  // not swap the list out for a terminal on the way past a row.
+  const hasPanes = (mv?.openSessions() ?? openSessions(layout)).size > 0;
   shellEl.dataset.route = hasPanes ? "attach" : "catalog";
 }
 
@@ -244,11 +277,18 @@ mv = createMultiView({
   onLayoutChange: scheduleSave,
 });
 let contentShowsMv = false;
-function showMultiView(): void {
+/** Put the multi-view in the content pane, without rendering it. A preview
+ *  renders once, on its own terms (`docs/PREVIEW.md`); a render here would
+ *  first re-mount the pane it is about to replace, and that mount takes the
+ *  keyboard away from the list being walked. */
+function ensureMultiView(): void {
   if (!contentShowsMv) {
     content.replaceChildren(mv.el);
     contentShowsMv = true;
   }
+}
+function showMultiView(): void {
+  ensureMultiView();
   mv.render();
   updateShellRoute();
 }
@@ -305,21 +345,25 @@ function mountSpawned(session: Session, placement?: { newTab?: boolean }): void
 // a new branch named after that name. Anything unresolvable (no projects
 // known yet, no command, no generated name) opens the form pre-filled with
 // what did resolve instead.
+async function spawnPresets(): Promise<SpawnPreset[]> {
+  try {
+    const info = await getDaemonInfo();
+    if (info.presets?.length) return info.presets;
+  } catch {
+    /* keep fallbacks */
+  }
+  return FALLBACK_PRESETS;
+}
+
 async function requestFastForward(): Promise<void> {
-  const [discovered, name] = await Promise.all([
+  const [discovered, handle] = await Promise.all([
     fetchProjects().catch(() => [] as Project[]),
     fetchNames(1)
       .then((batch) => batch.names[0])
       .catch(() => undefined),
   ]);
-  let presets: SpawnPreset[] = FALLBACK_PRESETS;
-  try {
-    const info = await getDaemonInfo();
-    if (info.presets?.length) presets = info.presets;
-  } catch {
-    /* keep fallbacks */
-  }
-  const resolved = resolveFastForward(discovered, presets, name, focusedProjectCwd());
+  const presets = await spawnPresets();
+  const resolved = resolveFastForward(discovered, presets, handle, focusedProjectCwd());
   const req = buildFastForwardRequest(resolved);
   if (req) {
     try {
@@ -340,45 +384,159 @@ async function requestFastForward(): Promise<void> {
   });
 }
 
-// Keyboard pair (#67): `n` opens the spawn modal, `N` fast-forwards a spawn.
-// Ignored while typing anywhere (form fields, the terminal's hidden
-// textarea, search) so an attached session's keys are never hijacked.
-document.addEventListener("keydown", (e) => {
-  if (e.ctrlKey || e.altKey || e.metaKey) return;
-  if (isTypingTarget(e.target)) return;
-  // The help overlay owns the keyboard while it is up.
-  if (isHelpOpen()) return;
-  if (e.key === "n") {
-    e.preventDefault();
-    requestOpenSpawn();
-  } else if (e.key === "N") {
-    e.preventDefault();
-    void requestFastForward();
+// Enter on a `~` row in the command bar (docs/COMMAND-BAR.md): the same
+// fast-forward spawn, aimed at the chosen directory instead of the most recent
+// project. A directory the project scan never saw stands in as its own project;
+// one outside any repo spawns without a worktree, since there is no repo to cut
+// a branch from. Anything still unresolved opens the pre-filled form.
+async function requestSpawnInDirectory(path: string): Promise<void> {
+  const [discovered, handle] = await Promise.all([
+    fetchProjects().catch(() => [] as Project[]),
+    fetchNames(1)
+      .then((batch) => batch.names[0])
+      .catch(() => undefined),
+  ]);
+  const presets = await spawnPresets();
+  const known = discovered.find((p) => p.path === path);
+  const project: Project = known ?? { path, name: path.split("/").filter(Boolean).pop() ?? path };
+  const resolved = resolveFastForward([project], presets, handle, path);
+  const req = buildFastForwardRequest(resolved);
+  if (req) {
+    const inRepo =
+      known !== undefined ||
+      (await gitRoot(path)
+        .then((r) => !!r.root)
+        .catch(() => false));
+    if (!inRepo) delete req.worktree;
+    try {
+      mountSpawned(await createSession(req));
+      return;
+    } catch {
+      // A failed POST degrades to the pre-filled form, never a dead row.
+    }
   }
+  openSpawnModal({
+    seed: fastForwardSeed(resolved),
+    onSuccess: (session) => mountSpawned(session),
+  });
+}
+
+document.addEventListener(SPAWN_DIRECTORY_EVENT, (ev) => {
+  void requestSpawnInDirectory((ev as CustomEvent<string>).detail);
 });
 
-// Ctrl+Shift+H moves the keyboard between the session list and the pane, the
-// web counterpart of the TUI's `ctrl-w h`. It has to be a chord: an attached
-// terminal owns every plain keystroke, so nothing unmodified could ever get
-// the focus back out of it.
-window.addEventListener("keydown", (e) => {
-  if (!e.ctrlKey || !e.shiftKey || e.altKey || e.metaKey) return;
-  if (e.key !== "H" && e.key !== "h") return;
-  e.preventDefault();
-  if (sidebar.hasListFocus()) {
-    pool.focusTerminal();
-  } else {
-    drawer.open(); // no-op on desktop; on mobile the list is off-canvas
-    sidebar.focusList();
-  }
-});
+// The global half of the command registry (#148). Two sets, because they
+// differ in one thing: the help overlay owns the keyboard while it is up, so
+// the plain keys go deaf behind it while the focus chord does not — an
+// attached terminal must never be able to trap the focus keys.
+//
+// `n` opens the spawn modal, `N` fast-forwards a spawn (#67). Both are plain
+// keys, so `isTypingTarget` inside the set keeps them out of form fields and the terminal's
+// hidden textarea.
+const spawnKeys = new CommandSet(
+  defineCommands({
+    "spawn.open": () => requestOpenSpawn(),
+    "spawn.fastForward": () => void requestFastForward(),
+  }),
+);
 
-// Tab in the session list hands the keyboard to the pane; Escape in the pane
-// hands it back — the pair the TUI gets from `tab` and `esc`.
-document.addEventListener(FOCUS_PANE_EVENT, () => pool.focusTerminal());
-document.addEventListener(FOCUS_SIDEBAR_EVENT, () => {
-  drawer.open(); // no-op on desktop; on mobile the list is off-canvas
-  sidebar.focusList();
+// Leader-h moves the keyboard between the session list and the pane, the web
+// counterpart of the TUI's `ctrl-w h`. It has to be a chord behind the
+// leader: an attached terminal owns every plain keystroke, and Ctrl+Shift+H
+// is already claimed by the browser (history), so nothing unmodified — or
+// modified with a common browser chord — could get the focus back out of it.
+//
+// This set also owns the leader (`[tui].leader`, `ctrl-a` by default, served
+// on `/api/info`): it holds the key as a partial chord and takes select-all off
+// it, so the escape hatch docs/COMMAND-BAR.md describes has somewhere to land
+// (#149).
+let currentLeader = DEFAULT_LEADER;
+
+function buildFocusKeys(leader: string): CommandSet {
+  return new CommandSet(
+    defineCommands(
+      {
+        "focus.toggle": () => {
+          if (sidebar.hasListFocus()) {
+            pool.focusTerminal();
+          } else {
+            drawer.open(); // no-op on desktop; on mobile the list is off-canvas
+            sidebar.focusList();
+          }
+        },
+        // The escape hatch: binding ctrl-k takes readline's
+        // kill-to-end-of-line away from every pane, and leader ctrl-k gives it
+        // back as the literal 0x0B byte (docs/COMMAND-BAR.md). It resolves in
+        // this set, ahead of the bar's, so the chord never opens the bar.
+        "pane.literalCtrlK": () => pool.sendToFocused("\x0b"),
+        // The leader itself, pressed twice, tmux-style: sends one literal
+        // leader byte and clears the pending chord instead of resolving as a
+        // dead chord (docs/COMMAND-BAR.md, #158). Built from the leader, not a
+        // hardcoded byte, so a rebound leader sends its own.
+        "pane.literalLeader": () => pool.sendToFocused(controlByte(leader)),
+      },
+      leader,
+    ),
+    { leader },
+  );
+}
+
+let focusKeys = buildFocusKeys(DEFAULT_LEADER);
+
+/** Rebind the leader-owning set to the daemon's leader. Re-registering the
+ *  same command ids replaces them, so the help overlay and the command bar —
+ *  both of which render the published registry when they open — show the
+ *  configured chord rather than the default. */
+function useLeader(leader: string): void {
+  if (leader === currentLeader) return;
+  currentLeader = leader;
+  focusKeys = buildFocusKeys(leader);
+}
+
+// Ctrl+K opens the command bar (docs/COMMAND-BAR.md). It is a registry command
+// like any other, so the `?` overlay lists it without a second list.
+const openBar = () => {
+  // Opening while a session is previewed discards the preview first, like
+  // any other real change (docs/PREVIEW.md): the bar is not previewed into.
+  schedulePreview.cancel();
+  mv?.previewSession(null);
+  openCommandBar({ sessions: [...store.snapshot().sessions.values()], homeDir });
+};
+
+const barKeys = new CommandSet(defineCommands({ "bar.open": () => openBar() }));
+
+// The sidebar's search field is the touch entry point (#157): no `ctrl-k` on a
+// phone, so the field the operator already reaches for opens the same bar.
+document.addEventListener(OPEN_COMMAND_BAR_EVENT, () => openBar());
+
+// Capture phase: an attached xterm swallows every keystroke it is given, so the
+// bar's binding has to be seen ahead of the terminal (docs/COMMAND-BAR.md).
+window.addEventListener(
+  "keydown",
+  (e) => {
+    // The bar owns the keyboard while it is up; its own input handles the keys.
+    if (isCommandBarOpen()) return;
+    if (focusKeys.handle(e)) return;
+    // The help overlay owns the keyboard while it is up.
+    if (isHelpOpen()) return;
+    // The pane's hidden textarea is not a typing target for the bar: ctrl-k is
+    // seen ahead of xterm and opens the bar (#152). A real form field — the
+    // spawn form's inputs — keeps its own Ctrl+K.
+    if (!isBarTypingTarget(e.target) && barKeys.handle(e)) return;
+    spawnKeys.handle(e);
+  },
+  true,
+);
+
+
+// Tab in the session list hands the keyboard to the pane; leader-h (focus.toggle,
+// above) hands it back the other way.
+document.addEventListener(FOCUS_PANE_EVENT, () => {
+  // Handing the keyboard to a previewed pane is choosing it: the preview stops
+  // being provisional rather than snapping back the moment the list blurs.
+  const previewed = mv.previewedSessionId();
+  if (previewed) focusSession(previewed);
+  pool.focusTerminal();
 });
 
 /** Open/focus a session and reflect it in the shell chrome. Shared by the
@@ -386,6 +544,7 @@ document.addEventListener(FOCUS_SIDEBAR_EVENT, () => {
  *  on `hashchange` alone — a split or drag can move focus without the hash
  *  changing, leaving a click back onto that session's row silently ignored. */
 function focusSession(sessionId: string): void {
+  schedulePreview.cancel();
   showMultiView();
   mv.openSession(sessionId);
   updateShellRoute();