Merge remote-tracking branch 'origin/main' into timbre

A Claude Code or Codex spawn now asks for the structured view unless the
operator says otherwise: the two spawn forms open with the box ticked and
`maestro spawn` takes `--terminal` to opt out. Once the operator works the
toggle, a command change no longer re-ticks it under them.

The support predicate moves to `maestro_protocol::display` so all three
clients gate on the same resolution.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>

Cargo.lock

@@ -1467,6 +1467,7 @@ dependencies = [
  "maestro-cli",
  "maestro-daemon",
  "maestro-tui",
+ "tempfile",
  "tokio",
  "tracing-subscriber",
 ]

crates/maestro-acp/Cargo.toml

@@ -5,7 +5,7 @@ edition.workspace = true
 license.workspace = true
 repository.workspace = true
 publish.workspace = true
-description = "ACP client role: one claude-code-acp child per structured session"
+description = "ACP client role: one provider adapter child per structured session"
 
 [dependencies]
 agent-client-protocol.workspace = true

crates/maestro-acp/src/lib.rs

@@ -1,5 +1,5 @@
-//! ACP client role for the daemon (#134): one `claude-code-acp` child per
-//! structured session.
+//! ACP client role for the daemon: one provider adapter 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
@@ -9,10 +9,10 @@
 //!
 //! **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.
+//! adapter uses the provider's own file and command tools 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 with
+//! a real implementation.
 //!
 //! Every `session/update` notification the adapter sends lands on an
 //! unbounded channel the session owns ([`AcpSession::take_updates`]). Nothing
@@ -96,8 +96,8 @@ 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.
+/// declared failed. The real adapters boot a node process and their provider
+/// client 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

crates/maestro-cli/src/cli.rs

@@ -92,6 +92,14 @@ pub struct SpawnArgs {
     /// there.
     #[arg(long)]
     pub existing_branch: bool,
+    /// Run a Claude Code or Codex session in a plain terminal instead of the
+    /// structured (ACP) view it otherwise gets by default.
+    #[arg(long, conflicts_with = "structured")]
+    pub terminal: bool,
+    /// Ask for the structured (ACP) view explicitly. Only Claude Code and
+    /// Codex commands have an adapter; the daemon refuses anything else.
+    #[arg(long)]
+    pub structured: bool,
     /// After spawning, attach immediately.
     #[arg(long, short = 'a')]
     pub attach: bool,

crates/maestro-cli/src/sessions.rs

@@ -3,7 +3,7 @@
 use std::collections::HashMap;
 use std::io::Write;
 
-use maestro_protocol::display::abbreviate_dir;
+use maestro_protocol::display::{abbreviate_dir, supports_structured_view};
 use maestro_protocol::{
     ActivityState, ClientError, CreateSessionRequest, DaemonClient, DaemonInfo, SendInputRequest,
     Session, SessionStatus, SessionView, WorktreeSpec,
@@ -51,7 +51,7 @@ pub async fn run_spawn(client: &DaemonClient, args: SpawnArgs) -> Result<Session
     };
 
     let body = CreateSessionRequest {
-        view: Default::default(),
+        view: spawn_view(&args),
         cwd: args.cwd.clone(),
         command: args.command.clone(),
         env,
@@ -61,6 +61,22 @@ pub async fn run_spawn(client: &DaemonClient, args: SpawnArgs) -> Result<Session
     client.create_session(&body).await
 }
 
+/// The view a `maestro spawn` asks for: structured whenever the command
+/// resolves to an agent with an ACP adapter, since that is the richer session
+/// and the one both other clients now default to. `--terminal` opts out;
+/// `--structured` forces the request through even for a command this side
+/// does not recognise, leaving the refusal to the daemon.
+fn spawn_view(args: &SpawnArgs) -> SessionView {
+    if args.terminal {
+        return SessionView::Terminal;
+    }
+    if args.structured || supports_structured_view(&args.command) {
+        SessionView::Structured
+    } else {
+        SessionView::Terminal
+    }
+}
+
 /// `maestro kill`. A forced kill (#81) retains the guarded worktree instead
 /// of removing it; the outcome names what was kept so dispatch can say where
 /// the work went.
@@ -239,6 +255,62 @@ mod tests {
 
     use super::DaemonInfo;
 
+    use clap::Parser;
+
+    use crate::cli::{Cli, Command};
+
+    fn spawn_args(extra: &[&str]) -> crate::cli::SpawnArgs {
+        let mut argv = vec!["maestro", "spawn", "--cwd", "/tmp", "--command"];
+        argv.extend_from_slice(extra);
+        let cli = Cli::try_parse_from(argv).expect("parses");
+        let Command::Spawn(args) = cli.command else {
+            panic!("expected spawn")
+        };
+        args
+    }
+
+    /// The CLI follows the two interactive clients: a command with an ACP
+    /// adapter spawns structured unless `--terminal` says otherwise, and
+    /// `--structured` still forces the request for a command this side does
+    /// not recognise.
+    #[test]
+    fn spawn_defaults_to_structured_for_supported_agents() {
+        use super::spawn_view;
+        assert_eq!(
+            spawn_view(&spawn_args(&["claude"])),
+            SessionView::Structured
+        );
+        assert_eq!(
+            spawn_view(&spawn_args(&["npx codex exec"])),
+            SessionView::Structured
+        );
+        assert_eq!(spawn_view(&spawn_args(&["bash"])), SessionView::Terminal);
+        assert_eq!(
+            spawn_view(&spawn_args(&["claude", "--terminal"])),
+            SessionView::Terminal
+        );
+        assert_eq!(
+            spawn_view(&spawn_args(&["opencode", "--structured"])),
+            SessionView::Structured
+        );
+    }
+
+    #[test]
+    fn spawn_refuses_both_view_flags_at_once() {
+        let err = Cli::try_parse_from([
+            "maestro",
+            "spawn",
+            "--cwd",
+            "/tmp",
+            "--command",
+            "claude",
+            "--structured",
+            "--terminal",
+        ])
+        .unwrap_err();
+        assert!(err.to_string().contains("--terminal"), "{err}");
+    }
+
     fn session(cwd: &str, command: &str, id: u128) -> Session {
         Session {
             view: Default::default(),

crates/maestro-daemon/src/local_api.rs

@@ -12,7 +12,8 @@
 
 use std::sync::Arc;
 
-use axum::extract::{Path, Query, State};
+use axum::body::Bytes;
+use axum::extract::{DefaultBodyLimit, Path, Query, State};
 use axum::http::StatusCode;
 use axum::response::{IntoResponse, Response};
 use axum::routing::{any, delete, get, post};
@@ -70,6 +71,10 @@ pub fn router(state: LocalApiState) -> Router {
         .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_ATTACHMENT,
+            post(structured_attachment).layer(DefaultBodyLimit::max(20 * 1024 * 1024)),
+        )
         .route(routes::patterns::STRUCTURED_CANCEL, post(structured_cancel))
         .route(routes::patterns::STRUCTURED_CONFIG, post(structured_config))
         .route(
@@ -432,6 +437,46 @@ async fn structured_replay(
     }
 }
 
+#[derive(Deserialize)]
+struct AttachmentQuery {
+    name: String,
+}
+
+async fn structured_attachment(
+    State(s): State<LocalApiState>,
+    Path(id): Path<Uuid>,
+    Query(query): Query<AttachmentQuery>,
+    bytes: Bytes,
+) -> Response {
+    let name = query.name;
+    if name.is_empty()
+        || name.len() > 180
+        || name == "."
+        || name == ".."
+        || name
+            .chars()
+            .any(|c| c.is_control() || c == '/' || c == '\\')
+    {
+        return error_response(
+            StatusCode::BAD_REQUEST,
+            "invalid_filename",
+            "use a filename without directory separators, up to 180 bytes",
+        );
+    }
+    match s.manager.store_acp_attachment(id, &name, &bytes).await {
+        Ok(Some(path)) => Json(serde_json::json!({ "path": path })).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)
+        }
+    }
+}
+
 async fn structured_prompt(
     State(s): State<LocalApiState>,
     Path(id): Path<Uuid>,

crates/maestro-daemon/src/session.rs

@@ -604,6 +604,36 @@ impl SessionManager {
         Ok(Some(replay))
     }
 
+    /// Store attachment bytes for a live structured session.
+    pub async fn store_acp_attachment(
+        &self,
+        id: Uuid,
+        name: &str,
+        bytes: &[u8],
+    ) -> Result<Option<std::path::PathBuf>, SessionError> {
+        {
+            let sessions = self.inner.sessions.lock().await;
+            let record = sessions.get(&id).ok_or(SessionError::NotFound(id))?;
+            if !record.is_live_structured() {
+                return Ok(None);
+            }
+        }
+        let dir = self.inner.sidecar.dir().join(format!("{id}.attachments"));
+        tokio::fs::create_dir_all(&dir).await?;
+        let dir = tokio::fs::canonicalize(dir).await?;
+        let path = dir.join(format!("{}-{name}", Uuid::new_v4()));
+        let mut file = tokio::fs::OpenOptions::new()
+            .write(true)
+            .create_new(true)
+            .mode(0o600)
+            .open(&path)
+            .await?;
+        use tokio::io::AsyncWriteExt;
+        file.write_all(bytes).await?;
+        file.sync_all().await?;
+        Ok(Some(path))
+    }
+
     /// Subscribe to the two projections of a structured session's ACP log.
     ///
     /// The transcript snapshot and whole reduced state are folded once by the

crates/maestro-daemon/tests/local_api.rs

@@ -234,6 +234,60 @@ async fn structured_ws_sends_snapshot_then_live_projection() {
     );
 }
 
+#[tokio::test]
+async fn structured_attachments_preserve_bytes_and_reject_paths() {
+    let h = spawn("attachments").await;
+    let fake = FakeAcp::new();
+    let id = structured_session(&h, &fake).await;
+    let client = reqwest::Client::new();
+    let endpoint = url(
+        h.addr,
+        &format!("/api/sessions/{id}/structured/attachments"),
+    );
+    let bytes = vec![0, 255, 10, 13];
+    let response = client
+        .post(&endpoint)
+        .query(&[("name", "sample.bin")])
+        .body(bytes.clone())
+        .send()
+        .await
+        .unwrap();
+    assert_eq!(response.status(), 200);
+    let body: serde_json::Value = response.json().await.unwrap();
+    let path = body["path"].as_str().unwrap();
+    assert!(Path::new(path).is_absolute());
+    assert_eq!(std::fs::read(path).unwrap(), bytes);
+    for name in ["../escape", "a/b", "a\\b", "..", ""] {
+        let response = client
+            .post(&endpoint)
+            .query(&[("name", name)])
+            .body("text")
+            .send()
+            .await
+            .unwrap();
+        assert_eq!(response.status(), 400, "{name}");
+    }
+    let response = client
+        .post(&endpoint)
+        .query(&[("name", "large.bin")])
+        .body(vec![0; 20 * 1024 * 1024 + 1])
+        .send()
+        .await
+        .unwrap();
+    assert_eq!(response.status(), 413);
+    let response = client
+        .post(url(
+            h.addr,
+            &format!("/api/sessions/{}/structured/attachments", Uuid::new_v4()),
+        ))
+        .query(&[("name", "file.txt")])
+        .body("text")
+        .send()
+        .await
+        .unwrap();
+    assert_eq!(response.status(), 404);
+}
+
 #[tokio::test]
 async fn structured_prompt_rejects_a_second_in_flight_turn_and_cancel_clears_it() {
     let h = spawn("naps-laptop").await;

crates/maestro-daemon/tests/worktree.rs

@@ -405,15 +405,17 @@ 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.
+/// `git worktree add -b` alone fails outright when the branch already exists,
+/// even with the target directory free — a random handle commonly collides
+/// with one an earlier, already-removed worktree left behind. `add_new`
+/// sidesteps it on the branch name itself instead of erroring (#77).
 #[test]
-fn add_new_suffixes_when_branch_already_exists() {
+fn add_new_suffixes_branch_name_on_branch_collision() {
     let repo_dir = TempDir::new().unwrap();
     let repo = repo_dir.path().to_path_buf();
     init_repo(&repo);
 
-    // pre-create the branch
+    // pre-create the branch, unused by any worktree.
     let status = Command::new("git")
         .arg("-C")
         .arg(&repo)
@@ -425,9 +427,17 @@ fn add_new_suffixes_when_branch_already_exists() {
     let wt_root = TempDir::new().unwrap();
     let mgr = WorktreeManager::new(Some(wt_root.path().to_path_buf()));
 
-    let path = mgr.add_new(&repo, "feat/dup").unwrap();
+    let path = mgr
+        .add_new(&repo, "feat/dup")
+        .expect("sidesteps the branch collision");
     assert!(path.ends_with("feat/dup-2"), "{}", path.display());
-    assert!(path.is_dir());
+    assert!(path.exists());
+
+    // The pre-existing branch is untouched; the new worktree checked out the
+    // suffixed one instead of erroring or adopting `feat/dup`.
+    let branches = worktree_branches(&repo);
+    assert!(branches.contains(&"feat/dup-2".to_string()), "{branches:?}");
+    assert!(!branches.contains(&"feat/dup".to_string()), "{branches:?}");
 }
 
 /// The project picker lists linked worktrees as pickable rows, so `base_repo`

crates/maestro-e2e/tests/e2e.rs

@@ -383,13 +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 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`.)
+/// #66/#77: a second spawn onto the same branch used to be rejected outright;
+/// since the branch-collision suffixing landed, it succeeds instead — the
+/// second worktree lands on `<branch>-2` and the first stays untouched.
 #[tokio::test(flavor = "multi_thread")]
-async fn second_spawn_on_same_branch_is_rejected() {
+async fn second_spawn_on_same_branch_gets_suffixed() {
     let (_daemon, client) = bring_up().await;
 
     let base = TempDir::new().unwrap();
@@ -399,28 +397,33 @@ async fn second_spawn_on_same_branch_is_rejected() {
         .spawn_session(&worktree_req(base.path(), "feature/dup", true))
         .await
         .expect("first spawn");
-    let dup = client
-        .spawn_session(&worktree_req(base.path(), "feature/dup", false))
-        .await;
-    match dup {
-        Err(maestro_e2e::ClientError::Api(maestro_protocol::ClientError::Api { info, .. })) => {
-            assert_eq!(
-                info.code, "worktree_failed",
-                "expected worktree error: {info:?}"
-            );
-        }
-        other => panic!("expected rejection for duplicate branch, got {other:?}"),
-    }
+    let second = client
+        .spawn_session(&worktree_req(base.path(), "feature/dup", true))
+        .await
+        .expect("second spawn suffixes instead of rejecting");
 
-    // Exactly one registration, one directory, still usable.
-    // Count branch records only: the worktree path now contains the branch
-    // name too (`worktrees/feature/dup`), so a substring match over every line
-    // would count the same tree twice.
-    let holders = git_worktree_list(base.path())
-        .iter()
-        .filter(|w| w.as_str() == "branch refs/heads/feature/dup")
-        .count();
-    assert_eq!(holders, 1, "duplicate spawn must not register another tree");
+    let suffixed = base.path().join("worktrees").join("feature").join("dup-2");
+    assert_eq!(
+        second.cwd, suffixed,
+        "second worktree must land on the suffixed path"
+    );
+    assert!(suffixed.is_dir());
+
+    // Both registrations exist: the original branch, untouched, and the
+    // suffixed one the second spawn created.
+    let registrations = git_worktree_list(base.path());
+    assert!(
+        registrations
+            .iter()
+            .any(|l| l.as_str() == "branch refs/heads/feature/dup"),
+        "original branch must stay registered: {registrations:?}"
+    );
+    assert!(
+        registrations
+            .iter()
+            .any(|l| l.as_str() == "branch refs/heads/feature/dup-2"),
+        "suffixed branch must be registered too: {registrations:?}"
+    );
     assert!(
         base.path()
             .join("worktrees")
@@ -431,7 +434,8 @@ async fn second_spawn_on_same_branch_is_rejected() {
     );
 
     let _origin = throwaway_origin(base.path());
-    client.kill_session(first.id).await.expect("kill");
+    client.kill_session(first.id).await.expect("kill first");
+    client.kill_session(second.id).await.expect("kill second");
 }
 
 /// #66/#56: when the client picks a *linked worktree* as base_repo, placement

crates/maestro-protocol/src/display.rs

@@ -226,6 +226,15 @@ pub fn command_tool(command: &str) -> Option<&'static str> {
         .map(|(_, tool)| *tool)
 }
 
+/// Whether a command line resolves to an agent Maestro can run as a
+/// structured (ACP) session — Claude Code or Codex, the two adapters
+/// `docs/STRUCTURED-VIEW.md` lists. Every client gates its structured-view
+/// control on this, and the daemon rejects a `Structured` request for
+/// anything else, so the answer has to come from one place.
+pub fn supports_structured_view(command: &str) -> bool {
+    matches!(command_tool(command), Some("claude" | "codex"))
+}
+
 /// [`resolve`]'s outcome: the tokenized command line, and the index within it
 /// of the word that is the actual program (past every assignment/wrapper it
 /// resolved through).
@@ -1064,4 +1073,14 @@ mod tests {
         assert_eq!(tokenize("\"FOO=1\" claude").unwrap()[0].plain_eq, None);
         assert_eq!(tokenize("FOO\\=1 claude").unwrap()[0].plain_eq, None);
     }
+
+    #[test]
+    fn structured_view_support_follows_the_resolved_program() {
+        assert!(supports_structured_view("claude --resume"));
+        assert!(supports_structured_view("FOO=1 /usr/local/bin/codex exec"));
+        assert!(supports_structured_view("npx claude-code"));
+        assert!(!supports_structured_view("opencode"));
+        assert!(!supports_structured_view("bash -l"));
+        assert!(!supports_structured_view("claude-code-acp"));
+    }
 }

crates/maestro-protocol/src/lib.rs

@@ -123,7 +123,7 @@ pub struct Session {
     /// 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
+    /// The ACP session id the selected provider 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

crates/maestro-protocol/src/routes.rs

@@ -86,6 +86,11 @@ pub fn structured_prompt(id: Uuid) -> String {
     format!("{SESSIONS}/{id}/structured/prompt")
 }
 
+/// `POST /api/sessions/:id/structured/attachments` — upload a file.
+pub fn structured_attachment(id: Uuid) -> String {
+    format!("{SESSIONS}/{id}/structured/attachments")
+}
+
 /// `POST /api/sessions/:id/structured/cancel` — cancel an ACP turn.
 pub fn structured_cancel(id: Uuid) -> String {
     format!("{SESSIONS}/{id}/structured/cancel")
@@ -113,6 +118,7 @@ pub mod patterns {
     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_ATTACHMENT: &str = "/api/sessions/:id/structured/attachments";
     pub const STRUCTURED_CANCEL: &str = "/api/sessions/:id/structured/cancel";
     pub const STRUCTURED_CONFIG: &str = "/api/sessions/:id/structured/config";
     pub const STRUCTURED_APPROVAL: &str = "/api/sessions/:id/structured/approvals/:nonce";

crates/maestro-tui/src/app.rs

@@ -3053,17 +3053,19 @@ mod tests {
         let request = |view| CreateSessionRequest {
             view,
             cwd: std::path::PathBuf::from("/srv/work"),
-            command: "claude".into(),
+            command: "codex".into(),
             env: Default::default(),
             metadata: Default::default(),
             worktree: None,
         };
 
         let structured_id = Uuid::from_u128(188);
+        app.state.mode = Mode::Insert;
         app.submit_spawn(request(SessionView::Structured)).await;
         assert!(app.catalog.snapshot().sessions.is_empty());
         assert!(app.structured.contains_key(&structured_id));
         assert!(app.emulators.get(structured_id).is_none());
+        assert_eq!(app.state.mode, Mode::Normal);
 
         let terminal_id = Uuid::from_u128(187);
         app.submit_spawn(request(SessionView::Terminal)).await;

crates/maestro-tui/src/draft.rs

@@ -41,7 +41,7 @@ use std::time::{Duration, Instant};
 
 use chrono::{DateTime, Utc};
 use maestro_config::{builtin_presets, custom_preset};
-use maestro_protocol::display::{abbreviate_dir, command_tool};
+use maestro_protocol::display::{abbreviate_dir, supports_structured_view};
 use maestro_protocol::{
     BranchInfo, CreateSessionRequest, Project, SessionView, SpawnPreset, WorktreeSpec,
 };
@@ -91,7 +91,7 @@ pub enum DraftField {
     /// 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.
+    /// ACP-backed transcript instead of a terminal. Claude Code or Codex.
     StructuredToggle,
     /// Worktree on/off for this session (#65). Enter / Space toggles.
     WorktreeToggle,
@@ -255,9 +255,14 @@ 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.
+    /// ACP-backed structured transcript. Supported only when the resolved
+    /// command is Claude Code or Codex, and on by default whenever it is —
+    /// until the operator works the toggle themselves.
     pub structured_view: bool,
+    /// Set once the operator toggles structured view by hand. From then on a
+    /// command change never re-enables what they turned off, the same guard
+    /// `name_touched` gives the name field.
+    pub structured_view_touched: 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>,
@@ -298,7 +303,7 @@ impl Default for DraftPane {
         // while its data loads, and stay usable when the daemon reports none.
         let mut presets = builtin_presets();
         presets.push(custom_preset());
-        Self {
+        let mut draft = Self {
             id: NEXT_DRAFT_ID.fetch_add(1, std::sync::atomic::Ordering::Relaxed),
             presets,
             selected_preset: 0,
@@ -319,6 +324,7 @@ impl Default for DraftPane {
             worktree_enabled: true,
             advanced_collapsed: true,
             structured_view: false,
+            structured_view_touched: false,
             base_repo: None,
             probed_cwd: None,
             probe_seq: 0,
@@ -337,7 +343,11 @@ impl Default for DraftPane {
             // straight away, and Tab from here reaches the command tiles.
             focused_field: DraftField::DirPicker,
             home_dir: String::new(),
-        }
+        };
+        // The built-in tile the form opens on decides whether structured view
+        // starts ticked, exactly as a later preset list would.
+        draft.sync_structured_view();
+        draft
     }
 }
 
@@ -356,7 +366,7 @@ impl DraftPane {
             .position(|p| !p.command.is_empty())
             .unwrap_or(0);
         self.apply_seed_command();
-        self.clear_unsupported_structured_view();
+        self.sync_structured_view();
     }
 
     /// Land a seeded command on the tile that runs it: its own preset when the
@@ -673,18 +683,24 @@ impl DraftPane {
     }
 
     fn supports_structured_view(&self) -> bool {
-        command_tool(self.command()) == Some("claude")
+        supports_structured_view(self.command())
     }
 
-    fn clear_unsupported_structured_view(&mut self) {
+    /// Re-resolve the toggle after the command changed: an unsupported
+    /// command forces it off, a supported one turns it back on unless the
+    /// operator has already made the choice themselves.
+    fn sync_structured_view(&mut self) {
         if !self.supports_structured_view() {
             self.structured_view = false;
+        } else if !self.structured_view_touched {
+            self.structured_view = true;
         }
     }
 
     pub fn toggle_structured_view(&mut self) {
         if self.supports_structured_view() {
             self.structured_view = !self.structured_view;
+            self.structured_view_touched = true;
         }
     }
 
@@ -827,7 +843,7 @@ impl DraftPane {
         }
         self.selected_preset =
             ((self.selected_preset as i32) + delta).rem_euclid(len as i32) as usize;
-        self.clear_unsupported_structured_view();
+        self.sync_structured_view();
     }
 
     /// Step-one boxes surviving the type-to-filter, in display order. A
@@ -1130,7 +1146,7 @@ impl DraftPane {
                     DraftField::Preset | DraftField::Submit => {}
                     DraftField::CustomCommand => {
                         self.custom_command.handle_key(other);
-                        self.clear_unsupported_structured_view();
+                        self.sync_structured_view();
                     }
                     // Typing filters the list; the highlight resets to the top
                     // so a narrowed search always starts at its best match.
@@ -1888,18 +1904,39 @@ mod tests {
     }
 
     #[test]
-    fn structured_view_is_default_off_and_only_visible_for_claude_code() {
+    fn structured_view_is_default_on_and_visible_for_supported_agents() {
         let mut draft = DraftPane {
             advanced_collapsed: false,
             ..DraftPane::default()
         };
-        assert!(!draft.structured_view);
+        draft.set_presets(vec![
+            SpawnPreset {
+                id: "claude".into(),
+                label: "Claude".into(),
+                command: "claude".into(),
+            },
+            SpawnPreset {
+                id: "codex".into(),
+                label: "Codex".into(),
+                command: "codex".into(),
+            },
+            SpawnPreset {
+                id: "opencode".into(),
+                label: "OpenCode".into(),
+                command: "opencode".into(),
+            },
+        ]);
+        assert!(draft.structured_view, "on by default for a supported agent");
         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}");
+        assert!(rendered.contains("[x] structured view"), "{rendered}");
 
-        draft.toggle_structured_view();
-        assert!(draft.structured_view);
+        draft.cycle_preset(1);
+        assert_eq!(draft.command(), "codex");
+        assert!(
+            draft.structured_view,
+            "Codex keeps the structured selection"
+        );
         draft.cycle_preset(1);
         assert_eq!(draft.command(), "opencode");
         assert!(
@@ -1928,9 +1965,9 @@ mod tests {
 
     /// A custom command typed into the free-text field, run through the same
     /// resolver the daemon/web gate uses (`command_tool`, #199): a path, an
-    /// env prefix, or a wrapper still resolves to Claude, so the toggle stays
-    /// offered and the request carries `Structured`; an unrelated program
-    /// does not.
+    /// env prefix, or a wrapper still resolves to Claude Code or Codex, so
+    /// the toggle stays offered and the request carries `Structured`; an
+    /// unrelated program does not.
     #[test]
     fn structured_view_follows_command_resolution_for_custom_commands() {
         let cases: &[(&str, bool)] = &[
@@ -1952,6 +1989,16 @@ mod tests {
             ("yarn --silent dlx claude-code", true),
             ("bun x claude-code", true),
             ("\"/opt/my agent/claude\" --resume", true),
+            ("codex", true),
+            ("codex --full-auto", true),
+            ("CODEX=1 codex", true),
+            ("/usr/local/bin/codex exec", true),
+            ("npx codex", true),
+            ("sudo -u root codex", true),
+            ("env -i codex", true),
+            ("command codex", true),
+            ("pnpm --silent dlx codex", true),
+            ("\"/opt/my agent/codex\" exec", true),
             ("bash", false),
             ("opencode", false),
             ("/usr/local/bin/bash -l", false),
@@ -1973,16 +2020,16 @@ mod tests {
             };
             draft.selected_preset = draft.presets.len() - 1;
             draft.custom_command = crate::text_input::TextInput::with_value(command);
+            draft.sync_structured_view();
 
             assert_eq!(
                 draft.field_order().contains(&DraftField::StructuredToggle),
                 supported,
                 "toggle visibility for {command:?}"
             );
-            draft.toggle_structured_view();
             assert_eq!(
                 draft.structured_view, supported,
-                "toggle takes effect for {command:?}"
+                "default selection for {command:?}"
             );
             let view = draft.build_request().unwrap().view;
             assert_eq!(
@@ -1994,12 +2041,18 @@ mod tests {
                 },
                 "request view for {command:?}"
             );
+
+            draft.toggle_structured_view();
+            assert!(
+                !draft.structured_view,
+                "the toggle turns the default off for {command:?}"
+            );
         }
     }
 
     /// A configured preset (the spawn-form "alias" for a command) is gated
     /// the same way as free text: a preset whose command resolves to Claude
-    /// through a wrapper still offers structured view.
+    /// Code or Codex through a wrapper still offers structured view.
     #[test]
     fn structured_view_follows_command_resolution_for_presets() {
         let mut draft = DraftPane {
@@ -2014,6 +2067,11 @@ mod tests {
                 label: "Claude (npx)".into(),
                 command: "npx claude-code --resume".into(),
             },
+            SpawnPreset {
+                id: "codex-wrapped".into(),
+                label: "Codex (npx)".into(),
+                command: "npx codex exec".into(),
+            },
             SpawnPreset {
                 id: "aider".into(),
                 label: "Aider".into(),
@@ -2023,11 +2081,16 @@ mod tests {
 
         assert_eq!(draft.command(), "npx claude-code --resume");
         assert!(draft.field_order().contains(&DraftField::StructuredToggle));
-        draft.toggle_structured_view();
         assert!(draft.structured_view);
         assert_eq!(draft.build_request().unwrap().view, SessionView::Structured);
 
-        // Switching to a preset that does not resolve to Claude clears the
+        // Switching between supported presets preserves the selection.
+        draft.cycle_preset(1);
+        assert_eq!(draft.command(), "npx codex exec");
+        assert!(draft.structured_view);
+        assert_eq!(draft.build_request().unwrap().view, SessionView::Structured);
+
+        // Switching to a preset that does not resolve to an ACP agent clears the
         // stale selection instead of letting an invalid request through.
         draft.cycle_preset(1);
         assert_eq!(draft.command(), "aider");
@@ -2036,11 +2099,48 @@ mod tests {
         assert_eq!(draft.build_request().unwrap().view, SessionView::Terminal);
     }
 
-    /// Editing the custom-command text away from Claude clears an armed
+    /// The default only applies until the operator has an opinion: once they
+    /// untick the box, moving between supported commands leaves it unticked
+    /// instead of turning it back on under them.
+    #[test]
+    fn an_unticked_structured_view_survives_a_command_change() {
+        let mut draft = DraftPane {
+            picked_cwd: Some(PathBuf::from("/srv/work")),
+            worktree_enabled: false,
+            advanced_collapsed: false,
+            ..DraftPane::default()
+        };
+        draft.set_presets(vec![
+            SpawnPreset {
+                id: "claude".into(),
+                label: "Claude".into(),
+                command: "claude".into(),
+            },
+            SpawnPreset {
+                id: "codex".into(),
+                label: "Codex".into(),
+                command: "codex".into(),
+            },
+        ]);
+        assert!(draft.structured_view);
+
+        draft.toggle_structured_view();
+        assert!(!draft.structured_view);
+
+        draft.cycle_preset(1);
+        assert_eq!(draft.command(), "codex");
+        assert!(
+            !draft.structured_view,
+            "the operator's choice outranks the default"
+        );
+        assert_eq!(draft.build_request().unwrap().view, SessionView::Terminal);
+    }
+
+    /// Editing the custom-command text away from a supported agent clears an armed
     /// selection immediately, matching the preset-switch case above — an
     /// invalid `Structured` request can never reach `build_request`.
     #[test]
-    fn structured_view_clears_when_custom_command_edited_away_from_claude() {
+    fn structured_view_clears_when_custom_command_edited_away_from_supported_agent() {
         let mut draft = DraftPane {
             picked_cwd: Some(PathBuf::from("/srv/work")),
             worktree_enabled: false,
@@ -2049,22 +2149,22 @@ mod tests {
             ..DraftPane::default()
         };
         draft.selected_preset = draft.presets.len() - 1;
-        draft.custom_command = crate::text_input::TextInput::with_value("claude");
-        draft.toggle_structured_view();
+        draft.custom_command = crate::text_input::TextInput::with_value("codex");
+        draft.sync_structured_view();
         assert!(draft.structured_view);
 
         typed(&mut draft, " -p");
-        assert_eq!(draft.command(), "claude -p");
-        assert!(draft.structured_view, "still Claude, selection survives");
+        assert_eq!(draft.command(), "codex -p");
+        assert!(draft.structured_view, "still Codex, selection survives");
 
-        for _ in 0.."claude -p".chars().count() {
+        for _ in 0.."codex -p".chars().count() {
             draft.on_input(&InputKey::Backspace);
         }
         typed(&mut draft, "bash");
         assert_eq!(draft.command(), "bash");
         assert!(
             !draft.structured_view,
-            "editing the program away from claude clears the stale selection"
+            "editing the program away from Codex clears the stale selection"
         );
         assert_eq!(draft.build_request().unwrap().view, SessionView::Terminal);
     }

crates/maestro/Cargo.toml

@@ -29,3 +29,6 @@ tracing-subscriber.workspace = true
 maestro-cli = { path = "../maestro-cli", optional = true, default-features = false }
 maestro-daemon = { path = "../maestro-daemon", optional = true, default-features = false }
 maestro-tui = { path = "../maestro-tui", optional = true }
+
+[dev-dependencies]
+tempfile.workspace = true

crates/maestro/tests/subcommand_routing.rs

@@ -0,0 +1,102 @@
+//! Process-level routing for the umbrella `maestro` binary (#10): each
+//! enabled top-level subcommand must reach its own crate's runtime dispatch,
+//! not just parse successfully.
+//!
+//! A malformed `--config` file makes every crate's dispatch fail identically
+//! at config load, before any subcommand touches tmux, the network, or a
+//! terminal. That lets the assertions tell "clap parsed it but the handler
+//! never ran" (a usage error, exit 2) apart from "it dispatched into the real
+//! crate" (a `toml decode` runtime error via `main`'s `maestro: {e}` printer,
+//! exit 1).
+//!
+//! The absence tests below only compile when the matching feature is off, so
+//! they run under CI's per-feature-subset matrix (`--no-default-features
+//! --features cli|daemon|tui`) rather than the default all-features build.
+
+use std::io::Write;
+use std::path::PathBuf;
+use std::process::{Command, Output};
+
+fn bin() -> PathBuf {
+    PathBuf::from(env!("CARGO_BIN_EXE_maestro"))
+}
+
+fn bad_config() -> tempfile::NamedTempFile {
+    let mut f = tempfile::NamedTempFile::new().expect("create temp config file");
+    write!(f, "this is not valid toml {{{{{{").expect("write temp config");
+    f
+}
+
+fn run(args: &[&str]) -> Output {
+    Command::new(bin())
+        .args(args)
+        .output()
+        .unwrap_or_else(|e| panic!("spawn `maestro {args:?}`: {e}"))
+}
+
+/// Real dispatch happened: exit 1, `main`'s `"maestro: {e}"` prefix, and the
+/// config crate's error surfacing through — never clap's own usage-error
+/// page, which would mean the subcommand never reached its handler.
+fn assert_dispatched(out: &Output) {
+    let stderr = String::from_utf8_lossy(&out.stderr);
+    assert_eq!(out.status.code(), Some(1), "stderr:\n{stderr}");
+    assert!(stderr.starts_with("maestro: "), "stderr:\n{stderr}");
+    assert!(stderr.contains("toml decode"), "stderr:\n{stderr}");
+    assert!(!stderr.contains("Usage:"), "stderr:\n{stderr}");
+}
+
+/// Never reached a handler: clap rejected the subcommand outright because the
+/// feature that defines it is off. Only used by the `not(feature = "...")`
+/// tests below, which themselves only exist in a single-feature build.
+#[cfg(not(all(feature = "cli", feature = "daemon", feature = "tui")))]
+fn assert_unrecognized(out: &Output, name: &str) {
+    let stderr = String::from_utf8_lossy(&out.stderr);
+    assert_eq!(out.status.code(), Some(2), "stderr:\n{stderr}");
+    assert!(
+        stderr.contains("unrecognized subcommand"),
+        "stderr:\n{stderr}"
+    );
+    assert!(stderr.contains(name), "stderr:\n{stderr}");
+}
+
+#[cfg(feature = "cli")]
+#[test]
+fn list_dispatches_into_maestro_cli() {
+    let cfg = bad_config();
+    let out = run(&["list", "--config", cfg.path().to_str().unwrap()]);
+    assert_dispatched(&out);
+}
+
+#[cfg(not(feature = "cli"))]
+#[test]
+fn list_is_unrecognized_without_cli_feature() {
+    assert_unrecognized(&run(&["list"]), "list");
+}
+
+#[cfg(feature = "daemon")]
+#[test]
+fn daemon_dispatches_into_maestro_daemon() {
+    let cfg = bad_config();
+    let out = run(&["daemon", "--config", cfg.path().to_str().unwrap()]);
+    assert_dispatched(&out);
+}
+
+#[cfg(not(feature = "daemon"))]
+#[test]
+fn daemon_is_unrecognized_without_daemon_feature() {
+    assert_unrecognized(&run(&["daemon"]), "daemon");
+}
+
+#[cfg(feature = "tui")]
+#[test]
+fn tui_dispatches_into_maestro_tui() {
+    let cfg = bad_config();
+    let out = run(&["tui", "--config", cfg.path().to_str().unwrap()]);
+    assert_dispatched(&out);
+}
+
+#[cfg(not(feature = "tui"))]
+#[test]
+fn tui_is_unrecognized_without_tui_feature() {
+    assert_unrecognized(&run(&["tui"]), "tui");
+}

docs/INSTALL.md

@@ -195,25 +195,28 @@ 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`
+## Structured sessions: ACP adapters
 
-A session spawned with `view: Structured` (#134) runs Claude Code as a child
+A session spawned with `view: Structured` runs Claude Code or Codex 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:
+resolved session command selects the adapter binary, which must be on the
+session's `PATH` when the spawn request sets one, or the daemon's `PATH`
+otherwise. Install the adapter for each provider you use:
 
 ```sh
 npm install -g --prefix ~/.local @zed-industries/claude-code-acp
+npm install -g --prefix ~/.local @agentclientprotocol/codex-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
+That puts `claude-code-acp` and `codex-acp` in `~/.local/bin`, which must be on
+the applicable `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`).
+Claude adapter needs a logged-in Claude Code (`claude /login`); Codex uses the
+Codex CLI's or adapter's configured authentication.
 
 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
+with the provider-specific install command as its activity detail, so clients
+say 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

docs/STRUCTURED-VIEW.md

@@ -35,11 +35,27 @@ 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).
 
+## Choosing the view
+
+`view` is fixed at spawn and never changes. Every client picks it the same
+way, from the resolved command alone
+(`maestro_protocol::display::supports_structured_view`): a command that
+resolves to Claude Code or Codex spawns **Structured** by default, anything
+else spawns **Terminal**. The operator can override the default — the web and
+TUI spawn forms show the checkbox ticked and let it be unticked, and
+`maestro spawn` takes `--terminal` (or `--structured`, which sends the request
+even for a command the CLI does not recognise and lets the daemon refuse it).
+Once the operator works the toggle, a later command change never re-ticks it
+under them; it can still be forced off when the new command has no adapter.
+
+The daemon is the last word: a `Structured` request for a command with no
+adapter is refused there, whichever client sent it.
+
 ## The adapter
 
 The resolved structured command selects a provider adapter. Its binary is
-resolved by walking the session's `PATH` (when set on the spawn request), then
-the daemon's `PATH`, and taking the first executable with that name.
+resolved by walking the session's `PATH` when the spawn request sets one, or
+the daemon's `PATH` otherwise, and taking the first executable with that name.
 
 | Command | Adapter binary | Install command | Provider detail |
 | --- | --- | --- | --- |
@@ -302,6 +318,26 @@ pending decision, entirely on the daemon side:
 
 ## Prompt and cancel: bounded liveness
 
+The web composer accepts up to ten files through its attachment picker, file
+drop, or clipboard. Pasted text of at least 4,000 characters or 40 lines becomes
+a UTF-8 `.txt` attachment. Shorter pastes stay in the composer. Attachments can
+be removed before sending; failed sends retain the draft and attachments.
+Pastes also stay inline when all ten attachment slots are occupied or the text
+exceeds the 20 MiB file limit.
+
+On send, `POST /api/sessions/:id/structured/attachments?name=<filename>` uploads
+each file as raw bytes (20 MiB maximum) and returns its absolute `path`.
+Only live structured sessions accept uploads. Filenames are limited to 180
+bytes and cannot contain directory separators or control characters. Files get unique names and private
+file permissions in `<id>.attachments` beside the session sidecar. They persist
+across daemon restarts; removing a composer chip does not delete uploaded data.
+There is currently no automatic attachment cleanup.
+
+The prompt includes each filename and host path so the adapter can read it
+through its own file tools, including images when the provider supports them.
+These references are persisted in the ordinary user transcript row. Attachment
+bytes are not embedded in ACP messages or transcript history.
+
 `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

flake.nix

@@ -148,7 +148,7 @@
             pnpmDeps = (pkgs.fetchPnpmDeps.override { pnpm = pkgs.pnpm_10; }) {
               inherit (finalAttrs) pname version src;
               fetcherVersion = 3;
-              hash = "sha256-hOqiAbnjKsoQnV8lgto5HspDsLIb+48sNLkShIjCZPQ=";
+              hash = "sha256-AzF/rrhqbvl613hNsC18YSylBSVxtatg7fEiUEF1u2o=";
             };
 
             buildPhase = ''

web/package.json

@@ -6,7 +6,7 @@
   "packageManager": "pnpm@9.15.4",
   "scripts": {
     "dev": "vite",
-    "build": "tsc -b && vite build",
+    "build": "tsc -b tsconfig.build.json && vite build",
     "preview": "vite preview",
     "typecheck": "tsc -b --noEmit",
     "test": "vitest run",

web/src/api.ts

@@ -184,6 +184,15 @@ export async function sendStructuredPrompt(id: Uuid, prompt: string): Promise<vo
   );
 }
 
+export async function uploadStructuredFile(id: Uuid, file: File): Promise<{ path: string }> {
+  return jsonOrError(await fetch(`${routes.structuredAttachment(id)}?name=${encodeURIComponent(file.name)}`, {
+    method: "POST",
+    credentials: "same-origin",
+    headers: { "content-type": "application/octet-stream" },
+    body: file,
+  }));
+}
+
 /** Cancel a structured session's active ACP turn (#138). */
 export async function cancelStructuredTurn(id: Uuid): Promise<void> {
   await jsonOrError(

web/src/attach.ts

@@ -64,6 +64,7 @@ export function createAttachConnection(
     <div class="attach-body"></div>
   `;
 
+  const titleEl = el.querySelector(".attach-title") as HTMLSpanElement;
   const body = el.querySelector(".attach-body") as HTMLDivElement;
   const stateEl = el.querySelector(".attach-state") as HTMLSpanElement;
   const disconnectBtn = el.querySelector(".disconnect") as HTMLButtonElement;
@@ -323,6 +324,9 @@ export function createAttachConnection(
   let ws: WebSocket;
   let reconnectMs = INITIAL_RECONNECT_MS;
   let reconnectTimer: number | null = null;
+  // Snapshot replay starts at row zero, which can leave Codex at its oldest line.
+  // Follow it once per socket; later scrolling remains under the operator's control.
+  let awaitingReplay = true;
 
   const sendControl = (msg: ClientControl) => {
     if (ws.readyState !== WebSocket.OPEN) return;
@@ -342,6 +346,7 @@ export function createAttachConnection(
   };
 
   function connect(): void {
+    awaitingReplay = true;
     ws = new WebSocket(attachWsUrl(sessionId));
     ws.binaryType = "arraybuffer";
 
@@ -362,10 +367,20 @@ export function createAttachConnection(
         return;
       }
       if (ev.data instanceof ArrayBuffer) {
-        term.write(new Uint8Array(ev.data));
+        const replay = awaitingReplay;
+        awaitingReplay = false;
+        term.write(new Uint8Array(ev.data), () => {
+          if (replay) term.scrollToBottom();
+        });
       } else if (ev.data instanceof Blob) {
         // Some browsers may default to Blob despite binaryType="arraybuffer".
-        ev.data.arrayBuffer().then((b) => term.write(new Uint8Array(b)));
+        void ev.data.arrayBuffer().then((b) => {
+          const replay = awaitingReplay;
+          awaitingReplay = false;
+          term.write(new Uint8Array(b), () => {
+            if (replay) term.scrollToBottom();
+          });
+        });
       }
     };
 
@@ -463,6 +478,10 @@ export function createAttachConnection(
     // The closure above: the same bytes-out path keystrokes and the mobile key
     // bar already take.
     sendInput,
+    updateInfo(next: AttachInfo) {
+      titleEl.innerHTML = paneTitleHtml(sessionId, next);
+      titleEl.title = paneTitleAttr(sessionId, next);
+    },
     dispose() {
       if (disposed) return;
       disposed = true;

web/src/connections.test.ts

@@ -27,6 +27,7 @@ function fakeConn(kind: string, id: string) {
     sendInput(data: string) {
       sent.push({ id, data });
     },
+    updateInfo() {},
     dispose() {
       disposed.push(`${kind}:${id}`);
     },

web/src/connections.ts

@@ -110,6 +110,7 @@ export class ConnectionPool {
       } else {
         this.cache.delete(id);
         this.cache.set(id, conn); // LRU refresh
+        if (info) conn.updateInfo(info);
       }
     } else {
       conn = this.create(id, info);

web/src/pane.ts

@@ -4,6 +4,7 @@
 // transcript (structured.ts).
 
 import type { Uuid } from "./types.js";
+import type { AttachInfo } from "./paneTitle.js";
 
 export interface PaneConnection {
   readonly sessionId: Uuid;
@@ -21,6 +22,8 @@ export interface PaneConnection {
    *  literal-byte escape hatch, docs/COMMAND-BAR.md). A structured connection
    *  has no PTY, so this is a no-op there. */
   sendInput(data: string): void;
+  /** Refresh the pane header after the catalog renames a live session. */
+  updateInfo(info: AttachInfo): void;
   /** Fully disconnect and remove the element. */
   dispose(): void;
 }

web/src/routes.ts

@@ -47,6 +47,10 @@ export function structuredPrompt(id: Uuid): string {
   return `${session(id)}/structured/prompt`;
 }
 
+export function structuredAttachment(id: Uuid): string {
+  return `${session(id)}/structured/attachments`;
+}
+
 /** `POST /api/sessions/:id/structured/cancel` — cancel an ACP turn. */
 export function structuredCancel(id: Uuid): string {
   return `${session(id)}/structured/cancel`;

web/src/spawnForm.test.ts

@@ -26,15 +26,21 @@ describe("buildSpawnRequest", () => {
     expect(res).toEqual({ req: { cwd: base.cwd, command: base.command, metadata: {} } });
   });
 
-  it("requests structured view only for Claude Code", () => {
-    expect(buildSpawnRequest({ ...base, structuredView: true }, null)).toEqual({
-      req: {
-        cwd: base.cwd,
-        command: "claude",
-        metadata: { name: "amber-fox" },
-        view: "Structured",
-      },
-    });
+  it.each(["claude", "FOO=1 /usr/local/bin/codex", "env -i codex"])(
+    "requests structured view for resolved %s commands",
+    (command) => {
+      expect(buildSpawnRequest({ ...base, command, structuredView: true }, null)).toEqual({
+        req: {
+          cwd: base.cwd,
+          command,
+          metadata: { name: "amber-fox" },
+          view: "Structured",
+        },
+      });
+    },
+  );
+
+  it("does not request structured view for unsupported commands", () => {
     expect(
       buildSpawnRequest({ ...base, command: "opencode", structuredView: true }, null),
     ).toEqual({

web/src/spawnForm.ts

@@ -15,6 +15,13 @@ import { splitCommand } from "./toolIcon.js";
 import { abbreviateCwd } from "./types.js";
 import type { BranchInfo, CreateSessionRequest, Project, Session, SpawnPreset } from "./types.js";
 
+const STRUCTURED_VIEW_TOOLS = new Set(["claude", "codex"]);
+
+function supportsStructuredView(command: string): boolean {
+  const tool = splitCommand(command).tool;
+  return tool !== null && STRUCTURED_VIEW_TOOLS.has(tool);
+}
+
 /** Where a worktree's branch comes from: freshly created (default) or picked
  * from the repository's existing branches (#61). */
 export type WorktreeBranchMode = "new" | "existing";
@@ -68,7 +75,7 @@ export function buildSpawnRequest(
     metadata,
   };
 
-  if (values.structuredView && splitCommand(values.command).tool === "claude") {
+  if (values.structuredView && supportsStructuredView(values.command)) {
     req.view = "Structured";
   }
 
@@ -368,13 +375,23 @@ export function createSpawnForm(opts: SpawnFormOptions): SpawnFormHandle {
   // operator has already touched (#76).
   let commandTouched = false;
 
+  // Set once the operator works the checkbox themselves. Until then every
+  // command change re-derives the default (on for Claude Code and Codex, off
+  // for everything else); afterwards their choice outranks it, the same guard
+  // `commandTouched` gives the command field.
+  let structuredTouched = false;
+
   function updateStructuredAvailability(): void {
-    const supported = splitCommand(command).tool === "claude";
+    const supported = supportsStructuredView(command);
     structuredWrap.hidden = !supported;
     if (!supported) structuredView.checked = false;
+    else if (!structuredTouched) structuredView.checked = true;
   }
 
-  structuredView.addEventListener("change", emit);
+  structuredView.addEventListener("change", () => {
+    structuredTouched = true;
+    emit();
+  });
 
   cmdRaw.addEventListener("input", () => {
     if (selectedPresetId === "custom" || presets.find((p) => p.id === selectedPresetId)?.command === "") {

web/src/spawnFormStructured.test.ts

@@ -44,7 +44,7 @@ describe("spawn form structured view", () => {
     vi.unstubAllGlobals();
   });
 
-  it("is default-off and shown only for the resolved Claude Code command", async () => {
+  it("is default-on and shown for resolved Claude Code and Codex commands", async () => {
     stubApi();
     handle = createSpawnForm({ onSuccess() {} });
     document.body.appendChild(handle.el);
@@ -57,28 +57,55 @@ describe("spawn form structured view", () => {
     handle.el.querySelector<HTMLButtonElement>(".wt-toggle")!.click();
     expect(disclosure.hidden).toBe(false);
     expect(wrap.hidden).toBe(false);
-    expect(checkbox.checked).toBe(false);
+    expect(checkbox.checked).toBe(true);
 
-    handle.el.querySelector<HTMLButtonElement>('[data-id="opencode"]')!.click();
-    expect(wrap.hidden).toBe(true);
-
-    handle.el.querySelector<HTMLButtonElement>('[data-id="claude"]')!.click();
+    const custom = handle.el.querySelector<HTMLButtonElement>('[data-id="custom"]')!;
+    custom.click();
+    const command = handle.el.querySelector<HTMLInputElement>(".cmd-raw")!;
+    command.value = "FOO=1 /usr/local/bin/codex";
+    command.dispatchEvent(new Event("input"));
     expect(wrap.hidden).toBe(false);
+    expect(checkbox.checked).toBe(true);
+
+    command.value = "opencode";
+    command.dispatchEvent(new Event("input"));
+    expect(wrap.hidden).toBe(true);
+    expect(checkbox.checked).toBe(false);
   });
 
-  it("clears a checked value when the command changes away from Claude Code", async () => {
+  it("keeps an unchecked box unchecked across a command change", async () => {
     stubApi();
     handle = createSpawnForm({ onSuccess() {} });
     document.body.appendChild(handle.el);
     await drain();
 
     const checkbox = handle.el.querySelector<HTMLInputElement>("input[name=structured_view]")!;
+    expect(checkbox.checked).toBe(true);
     checkbox.click();
+    expect(checkbox.checked).toBe(false);
+
+    handle.el.querySelector<HTMLButtonElement>('[data-id="custom"]')!.click();
+    const command = handle.el.querySelector<HTMLInputElement>(".cmd-raw")!;
+    command.value = "codex";
+    command.dispatchEvent(new Event("input"));
+
+    expect(checkbox.checked).toBe(false);
+  });
+
+  it("clears the checked default when Codex changes to an unsupported command", async () => {
+    stubApi();
+    handle = createSpawnForm({ onSuccess() {} });
+    document.body.appendChild(handle.el);
+    await drain();
+
+    handle.el.querySelector<HTMLButtonElement>('[data-id="custom"]')!.click();
+    const command = handle.el.querySelector<HTMLInputElement>(".cmd-raw")!;
+    command.value = "env -i codex";
+    command.dispatchEvent(new Event("input"));
+
+    const checkbox = handle.el.querySelector<HTMLInputElement>("input[name=structured_view]")!;
     expect(checkbox.checked).toBe(true);
 
-    const custom = handle.el.querySelector<HTMLButtonElement>('[data-id="custom"]')!;
-    custom.click();
-    const command = handle.el.querySelector<HTMLInputElement>(".cmd-raw")!;
     command.value = "opencode";
     command.dispatchEvent(new Event("input"));
 
@@ -86,7 +113,33 @@ describe("spawn form structured view", () => {
     expect(checkbox.checked).toBe(false);
   });
 
-  it("emits Structured in the submitted request when selected", async () => {
+  it.each(["claude", "codex"])("emits Structured for a %s command by default", async (tool) => {
+    const requests = stubApi();
+    handle = createSpawnForm({
+      seed: { cwd: "/srv/work", cwdRawVisible: true, worktreeEnabled: false },
+      onSuccess() {},
+    });
+    document.body.appendChild(handle.el);
+    await drain();
+
+    if (tool === "codex") {
+      handle.el.querySelector<HTMLButtonElement>('[data-id="custom"]')!.click();
+      const command = handle.el.querySelector<HTMLInputElement>(".cmd-raw")!;
+      command.value = "codex";
+      command.dispatchEvent(new Event("input"));
+    }
+
+    handle.el.requestSubmit();
+    await drain();
+
+    expect(requests).toHaveLength(1);
+    expect(JSON.parse(String(requests[0].body))).toMatchObject({
+      command: tool,
+      view: "Structured",
+    });
+  });
+
+  it("emits no view once the operator unticks the box", async () => {
     const requests = stubApi();
     handle = createSpawnForm({
       seed: { cwd: "/srv/work", cwdRawVisible: true, worktreeEnabled: false },
@@ -100,9 +153,6 @@ describe("spawn form structured view", () => {
     await drain();
 
     expect(requests).toHaveLength(1);
-    expect(JSON.parse(String(requests[0].body))).toMatchObject({
-      command: "claude",
-      view: "Structured",
-    });
+    expect(JSON.parse(String(requests[0].body)).view).toBeUndefined();
   });
 });

web/src/structured.test.ts

@@ -6,6 +6,7 @@ vi.mock("./api.js", async () => {
   return {
     ...actual,
     sendStructuredPrompt: vi.fn().mockResolvedValue(undefined),
+    uploadStructuredFile: vi.fn().mockResolvedValue({ path: "/uploads/pasted.txt" }),
     cancelStructuredTurn: vi.fn().mockResolvedValue(undefined),
     resolveStructuredApproval: vi.fn().mockResolvedValue(undefined),
     setStructuredConfig: vi.fn().mockResolvedValue(undefined),
@@ -16,6 +17,7 @@ import {
   cancelStructuredTurn,
   resolveStructuredApproval,
   sendStructuredPrompt,
+  uploadStructuredFile,
   setStructuredConfig,
 } from "./api.js";
 import { TOGGLE_DRAWER_EVENT } from "./drawer.js";
@@ -95,6 +97,53 @@ function mount(opts: {
 describe("structured connection: data flow", () => {
   beforeEach(() => vi.clearAllMocks());
 
+  it("converts long pasted text into a removable file and sends it without reply text", async () => {
+    const conn = mount({ sockets: [new FakeSocket()] });
+    const input = conn.el.querySelector("textarea")!;
+    const paste = new Event("paste", { bubbles: true, cancelable: true });
+    Object.defineProperty(paste, "clipboardData", { value: {
+      files: [], getData: () => "a".repeat(4000),
+    } });
+    input.dispatchEvent(paste);
+    expect(paste.defaultPrevented).toBe(true);
+    expect(input.value).toBe("");
+    expect(conn.el.querySelector(".structured-attachments")!.textContent).toContain("pasted-1.txt");
+    conn.el.querySelector("form")!.dispatchEvent(new Event("submit", { cancelable: true }));
+    await vi.waitFor(() => expect(sendStructuredPrompt).toHaveBeenCalledWith("s1", expect.stringContaining("/uploads/pasted.txt")));
+    expect(uploadStructuredFile).toHaveBeenCalledWith("s1", expect.objectContaining({ name: "pasted-1.txt", size: 4000 }));
+    conn.dispose();
+  });
+
+  it("leaves short pastes alone", () => {
+    const conn = mount({ sockets: [new FakeSocket()] });
+    const paste = new Event("paste", { bubbles: true, cancelable: true });
+    Object.defineProperty(paste, "clipboardData", { value: { files: [], getData: () => "hello" } });
+    conn.el.querySelector("textarea")!.dispatchEvent(paste);
+    expect(paste.defaultPrevented).toBe(false);
+    conn.dispose();
+  });
+
+  it("retains failed uploads for retry and lets the operator remove them", async () => {
+    vi.mocked(uploadStructuredFile).mockRejectedValueOnce(new Error("Upload failed"));
+    const conn = mount({ sockets: [new FakeSocket()] });
+    const input = conn.el.querySelector("textarea")!;
+    input.value = "Read this";
+    const paste = new Event("paste", { bubbles: true, cancelable: true });
+    Object.defineProperty(paste, "clipboardData", { value: {
+      files: [new File(["content"], "notes.txt")], getData: () => "",
+    } });
+    input.dispatchEvent(paste);
+    conn.el.querySelector("form")!.dispatchEvent(new Event("submit", { cancelable: true }));
+    await vi.waitFor(() => expect(input.disabled).toBe(false));
+    expect(input.value).toBe("Read this");
+    expect(sendStructuredPrompt).not.toHaveBeenCalled();
+    const remove = conn.el.querySelector<HTMLButtonElement>('[aria-label="Remove notes.txt"]')!;
+    expect(remove).not.toBeNull();
+    remove.click();
+    expect(conn.el.querySelector<HTMLElement>(".structured-attachments")!.hidden).toBe(true);
+    conn.dispose();
+  });
+
   it("renders every row from the initial snapshot", () => {
     const ws = new FakeSocket();
     const conn = mount({ sockets: [ws] });
@@ -115,6 +164,42 @@ describe("structured connection: data flow", () => {
     conn.dispose();
   });
 
+  it("shows turn details only while that footer is the conversation's final item", () => {
+    const ws = new FakeSocket();
+    const conn = mount({ sockets: [ws] });
+    const turnMeta = (id: string, elapsedMs: number) =>
+      row(id, "notice", {
+        maestroTurnMeta: { elapsedMs, contextTokens: 12_000, outcome: "completed", model: "codex" },
+      });
+    ws.open();
+    ws.emit({
+      type: "transcript_snapshot",
+      snapshot: {
+        cursor: 4,
+        rows: [
+          row("user:1", "user", { content: { type: "text", text: "first" } }),
+          turnMeta("turn:1", 1_000),
+          row("user:2", "user", { content: { type: "text", text: "second" } }),
+          turnMeta("turn:2", 2_000),
+        ],
+      },
+    });
+
+    expect(conn.el.querySelectorAll(".st-turn-meta")).toHaveLength(1);
+    expect(conn.el.querySelector(".st-turn-meta")?.textContent).toContain("2s");
+
+    ws.emit({
+      type: "projection_update",
+      transcript: {
+        type: "append",
+        row: row("user:3", "user", { content: { type: "text", text: "third" } }),
+      },
+      state: idleState,
+    });
+    expect(conn.el.querySelector(".st-turn-meta")).toBeNull();
+    conn.dispose();
+  });
+
   it("keeps state-only plan rows out of the transcript", () => {
     const ws = new FakeSocket();
     const conn = mount({ sockets: [ws] });
@@ -289,6 +374,7 @@ describe("structured connection: data flow", () => {
       transcript: { type: "append", row: row("agent:1", "agent_text", { content: { type: "text", text: "partial" } }) },
       state: idleState,
     });
+    expect(conn.el.querySelector('[data-row-id="agent:1"]')?.classList).toContain("st-row-enter");
     ws.emit({
       type: "projection_update",
       transcript: { type: "patch", row: row("agent:1", "agent_text", { content: { type: "text", text: "partial done" } }) },
@@ -296,6 +382,7 @@ describe("structured connection: data flow", () => {
     });
     const rows = conn.el.querySelectorAll(".st-row-agent");
     expect(rows).toHaveLength(1);
+    expect(rows[0].classList).not.toContain("st-row-enter");
     expect(conn.el.textContent).toContain("partial done");
     expect(conn.el.textContent).not.toContain("partial\n"); // the un-patched text is gone, not appended beside it
     conn.dispose();
@@ -321,7 +408,7 @@ describe("structured connection: data flow", () => {
     const groups = conn.el.querySelectorAll<HTMLElement>(".st-tool-group");
     expect(groups).toHaveLength(1);
     expect(groups[0].querySelector(".st-tool-group-head")!.textContent).toContain("2 tool calls");
-    expect(groups[0].querySelector<HTMLElement>(".st-tool-group-body")!.hidden).toBe(true);
+    expect(groups[0].querySelector<HTMLElement>(".st-tool-group-body")!.getAttribute("aria-hidden")).toBe("true");
     expect(conn.el.querySelector('[data-row-id="tool:3"]')?.closest(".st-tool-group")).toBeNull();
     conn.dispose();
   });
@@ -1253,7 +1340,7 @@ describe("structured connection: transcript scrolling", () => {
   it("keeps pinned appends and patches at the bottom after layout", () => {
     const ws = new FakeSocket();
     const conn = mount({ sockets: [ws] });
-    const { values } = metrics(conn, 600, 200);
+    const { scroll, values } = metrics(conn, 600, 200);
     ws.open();
     ws.emit({ type: "transcript_snapshot", snapshot: { cursor: 0, rows: [] } });
     runFrames();
@@ -1269,6 +1356,7 @@ describe("structured connection: transcript scrolling", () => {
     });
     runFrames();
     expect(values.top).toBe(520);
+    expect(scroll.style.scrollBehavior).toBe("smooth");
 
     values.height = 780;
     ws.emit({
@@ -1283,6 +1371,32 @@ describe("structured connection: transcript scrolling", () => {
     });
     runFrames();
     expect(values.top).toBe(580);
+    expect(scroll.style.scrollBehavior).toBe("smooth");
+    conn.dispose();
+  });
+
+  it("keeps follow-to-bottom immediate when reduced motion is requested", () => {
+    vi.stubGlobal("matchMedia", () => ({ matches: true }));
+    const ws = new FakeSocket();
+    const conn = mount({ sockets: [ws] });
+    const { scroll, values } = metrics(conn, 600, 200);
+    ws.open();
+    ws.emit({ type: "transcript_snapshot", snapshot: { cursor: 0, rows: [] } });
+    runFrames();
+
+    values.height = 720;
+    ws.emit({
+      type: "projection_update",
+      transcript: {
+        type: "append",
+        row: row("agent:1", "agent_text", { content: { type: "text", text: "quietly" } }),
+      },
+      state: idleState,
+    });
+    runFrames();
+
+    expect(values.top).toBe(520);
+    expect(scroll.style.scrollBehavior).toBe("");
     conn.dispose();
   });
 

web/src/structured.ts

@@ -10,6 +10,7 @@ import {
   cancelStructuredTurn,
   resolveStructuredApproval,
   sendStructuredPrompt,
+  uploadStructuredFile,
   setStructuredConfig,
   structuredWsUrl,
 } from "./api.js";
@@ -90,7 +91,12 @@ export function createStructuredConnection(
           <span class="structured-activity-text">Thinking</span>
         </div>
         <form class="structured-composer">
+          <button type="button" class="btn btn-ghost btn-icon structured-attach" aria-label="Attach files" title="Attach files (up to 20 MiB each)">
+            <svg width="20" height="20" viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="1.5" aria-hidden="true"><path d="m8 12 7-7a3 3 0 0 1 4 4L9 19a5 5 0 0 1-7-7L12 2M5 14l9-9"/></svg>
+          </button>
+          <input class="structured-file-input" type="file" multiple hidden>
           <div class="structured-input-wrap">
+            <div class="structured-attachments" aria-label="Attachments" aria-live="polite" hidden></div>
             <div id="structured-command-menu-${sessionId}" class="structured-command-menu"
               role="listbox" hidden></div>
             <textarea class="structured-input" rows="1" placeholder="Reply, or / for commands…"
@@ -114,6 +120,7 @@ export function createStructuredConnection(
   `;
 
   const stateEl = el.querySelector(".attach-state") as HTMLSpanElement;
+  const titleEl = el.querySelector(".attach-title") as HTMLSpanElement;
   const configEl = el.querySelector(".structured-config") as HTMLDivElement;
   const configTrigger = el.querySelector(".structured-config-trigger") as HTMLButtonElement;
   const configMenu = el.querySelector(".structured-config-menu") as HTMLDivElement;
@@ -127,6 +134,79 @@ export function createStructuredConnection(
   const input = el.querySelector(".structured-input") as HTMLTextAreaElement;
   const sendBtn = el.querySelector(".structured-send") as HTMLButtonElement;
   const cancelBtn = el.querySelector(".structured-cancel") as HTMLButtonElement;
+  const attachBtn = el.querySelector(".structured-attach") as HTMLButtonElement;
+  const fileInput = el.querySelector(".structured-file-input") as HTMLInputElement;
+  const attachmentEl = el.querySelector(".structured-attachments") as HTMLDivElement;
+  type Attachment = { file: File; path?: string };
+  let attachments: Attachment[] = [];
+  let uploading = false;
+  let pasteCount = 0;
+
+  function renderAttachments(): void {
+    attachmentEl.replaceChildren();
+    attachmentEl.hidden = attachments.length === 0;
+    for (const attachment of attachments) {
+      const chip = document.createElement("span");
+      chip.className = "structured-attachment";
+      const label = document.createElement("span");
+      label.textContent = attachment.file.name;
+      label.title = `${attachment.file.name} (${attachment.file.size.toLocaleString()} bytes)`;
+      const remove = document.createElement("button");
+      remove.type = "button";
+      remove.textContent = "×";
+      remove.setAttribute("aria-label", `Remove ${attachment.file.name}`);
+      remove.disabled = input.disabled;
+      remove.addEventListener("click", () => {
+        attachments = attachments.filter((item) => item !== attachment);
+        renderAttachments();
+      });
+      chip.append(label, remove);
+      attachmentEl.append(chip);
+    }
+  }
+
+  function addFiles(files: File[]): void {
+    if (input.disabled || disposed) return;
+    for (const file of files) {
+      if (file.size > 20 * 1024 * 1024) {
+        showError(`${file.name} exceeds 20 MiB. Choose a smaller file.`);
+      } else if (attachments.length >= 10) {
+        showError("Attach up to 10 files per message.");
+      } else {
+        attachments.push({ file });
+      }
+    }
+    renderAttachments();
+  }
+  attachBtn.addEventListener("click", () => fileInput.click());
+  fileInput.addEventListener("change", () => {
+    addFiles(Array.from(fileInput.files ?? []));
+    fileInput.value = "";
+  });
+  composerForm.addEventListener("dragover", (event) => {
+    if (event.dataTransfer?.types.includes("Files")) event.preventDefault();
+  });
+  composerForm.addEventListener("drop", (event) => {
+    if (!event.dataTransfer?.files.length) return;
+    event.preventDefault();
+    addFiles(Array.from(event.dataTransfer.files));
+  });
+  input.addEventListener("paste", (event) => {
+    const clipboard = event.clipboardData;
+    if (!clipboard || input.disabled) return;
+    if (clipboard.files.length) {
+      event.preventDefault();
+      addFiles(Array.from(clipboard.files));
+      return;
+    }
+    const text = clipboard.getData("text/plain");
+    if (text.length < 4000 && text.split("\n").length < 40) return;
+    if (attachments.length >= 10 || new Blob([text]).size > 20 * 1024 * 1024) return;
+    event.preventDefault();
+    addFiles([new File([text], `pasted-${++pasteCount}.txt`, { type: "text/plain" })]);
+    input.setRangeText("", input.selectionStart, input.selectionEnd, "end");
+    autoResize();
+  });
 
   disconnectBtn.addEventListener("click", () => opts.onRequestClose?.(sessionId));
   // Mobile-only (CSS hides it on desktop, where the sidebar is always in
@@ -148,6 +228,7 @@ export function createStructuredConnection(
   const rowEls = new Map<string, HTMLElement>();
   const expandedRowIds = new Set<string>();
   const expandedGroupIds = new Set<string>();
+  const enteringRowIds = new Set<string>();
   const groupEls = new Map<string, HTMLElement>();
   let state: ReducedState = { turn: idleTurn() };
   let pendingApprovalRowId: string | null = null;
@@ -171,7 +252,20 @@ export function createStructuredConnection(
   let scrollWorkActive = true;
   let parkedScrollTop: number | null = null;
   let scrollFrame: number | null = null;
-  let pendingScroll: { top: number; follow: boolean } | null = null;
+  let pendingScroll: { top: number; follow: boolean; smooth: boolean } | null = null;
+  let smoothScrollTimer: number | null = null;
+  let smoothFollowing = false;
+
+  function reduceMotion(): boolean {
+    return window.matchMedia?.("(prefers-reduced-motion: reduce)").matches ?? false;
+  }
+
+  function stopSmoothFollow(): void {
+    if (smoothScrollTimer !== null) window.clearTimeout(smoothScrollTimer);
+    smoothScrollTimer = null;
+    smoothFollowing = false;
+    scrollEl.style.removeProperty("scroll-behavior");
+  }
 
   function cancelScrollFrame(): void {
     if (scrollFrame !== null) window.cancelAnimationFrame(scrollFrame);
@@ -179,15 +273,17 @@ export function createStructuredConnection(
     pendingScroll = null;
   }
 
-  function beginTranscriptLayout(forceBottom = false): void {
+  function beginTranscriptLayout(forceBottom = false, smooth = false): void {
     if (!scrollWorkActive || disposed) return;
     if (pendingScroll) {
       if (forceBottom) pendingScroll.follow = true;
+      if (smooth) pendingScroll.smooth = true;
       return;
     }
     pendingScroll = {
       top: scrollEl.scrollTop,
       follow: forceBottom || followingBottom,
+      smooth,
     };
   }
 
@@ -198,19 +294,30 @@ export function createStructuredConnection(
       const pending = pendingScroll;
       pendingScroll = null;
       if (!pending || disposed || !scrollWorkActive) return;
-      scrollEl.scrollTop = pending.follow
+      const target = pending.follow
         ? Math.max(0, scrollEl.scrollHeight - scrollEl.clientHeight)
         : pending.top;
+      if (pending.follow && pending.smooth && !reduceMotion()) {
+        smoothFollowing = true;
+        scrollEl.style.scrollBehavior = "smooth";
+        scrollEl.scrollTop = target;
+        if (smoothScrollTimer !== null) window.clearTimeout(smoothScrollTimer);
+        smoothScrollTimer = window.setTimeout(() => stopSmoothFollow(), 220);
+      } else {
+        stopSmoothFollow();
+        scrollEl.scrollTop = target;
+      }
     });
   }
 
-  function updateTranscriptLayout(update: () => void, forceBottom = false): void {
-    beginTranscriptLayout(forceBottom);
+  function updateTranscriptLayout(update: () => void, forceBottom = false, smooth = false): void {
+    beginTranscriptLayout(forceBottom, smooth);
     update();
     finishTranscriptLayout();
   }
 
   function onTranscriptScroll(): void {
+    if (smoothFollowing) return;
     const distance = scrollEl.scrollHeight - scrollEl.clientHeight - scrollEl.scrollTop;
     followingBottom = distance <= FOLLOW_BOTTOM_THRESHOLD_PX;
     cancelScrollFrame();
@@ -218,12 +325,19 @@ export function createStructuredConnection(
 
   function onTranscriptClick(event: Event): void {
     if ((event.target as Element | null)?.closest(".st-tool-head, .st-tool-group-head")) {
-      beginTranscriptLayout();
+      beginTranscriptLayout(false, true);
     }
   }
 
+  function settleDisclosureLayout(): void {
+    finishTranscriptLayout();
+    window.setTimeout(() => updateTranscriptLayout(() => {}, false, true), 190);
+  }
+
   scrollEl.addEventListener("scroll", onTranscriptScroll);
   scrollEl.addEventListener("click", onTranscriptClick, true);
+  scrollEl.addEventListener("wheel", stopSmoothFollow, { passive: true });
+  scrollEl.addEventListener("touchstart", stopSmoothFollow, { passive: true });
 
   function lastRowIdOfKind(kind: TranscriptRowKind): string | null {
     for (let i = rows.length - 1; i >= 0; i--) if (rows[i].kind === kind) return rows[i].id;
@@ -268,10 +382,11 @@ export function createStructuredConnection(
       (expanded) => {
         if (expanded) expandedRowIds.add(row.id);
         else expandedRowIds.delete(row.id);
-        finishTranscriptLayout();
+        settleDisclosureLayout();
       },
     );
     if (!el) return null;
+    if (enteringRowIds.has(row.id)) el.classList.add("st-row-enter");
     if (el.querySelector(".st-tool-head")?.getAttribute("aria-expanded") !== "true") {
       expandedRowIds.delete(row.id);
     }
@@ -328,9 +443,12 @@ export function createStructuredConnection(
           (expanded) => {
             if (expanded) expandedGroupIds.add(groupId);
             else expandedGroupIds.delete(groupId);
-            finishTranscriptLayout();
+            settleDisclosureLayout();
           },
         );
+        if (groupRows.some((toolRow) => enteringRowIds.has(toolRow.id))) {
+          groupEl.classList.add("st-row-enter");
+        }
         groupEls.set(groupId, groupEl);
         children.push(groupEl);
         continue;
@@ -340,7 +458,15 @@ export function createStructuredConnection(
       rowEls.set(row.id, rowEl);
       children.push(rowEl);
     }
-    rowsEl.replaceChildren(...children);
+    // A completed turn's footer is useful as the conversation's current
+    // tail, but repeating duration/model/token summaries throughout history
+    // makes them read like transcript content. Keep only a footer that is the
+    // final visible item; appending the next turn naturally retires it.
+    const visibleChildren = children.filter(
+      (child, index) => !child.classList.contains("st-turn-meta") || index === children.length - 1,
+    );
+    rowsEl.replaceChildren(...visibleChildren);
+    enteringRowIds.clear();
     if (restoreToolFocus && focusedRowId) {
       rowEls.get(focusedRowId)?.querySelector<HTMLButtonElement>(".st-tool-head")?.focus();
     } else if (restoreGroupFocus && focusedGroupId) {
@@ -368,6 +494,7 @@ export function createStructuredConnection(
     if (!delta) return;
     updateTranscriptLayout(() => {
       if (delta.type === "append") {
+        if (receivedSnapshot) enteringRowIds.add(delta.row.id);
         rowIndex.set(delta.row.id, rows.length);
         rows.push(delta.row);
       } else if (delta.type === "patch") {
@@ -388,7 +515,7 @@ export function createStructuredConnection(
       }
       rebuildTranscript();
       syncAvailableCommands();
-    });
+    }, false, true);
   }
 
   function sessionConfigOptions(): AcpSessionConfigOption[] {
@@ -479,9 +606,12 @@ export function createStructuredConnection(
   }
 
   function renderComposerState(): void {
-    const active = state.turn.responding || state.turn.thinking || awaitingBeginGeneration !== null;
+    const active = uploading || state.turn.responding || state.turn.thinking || awaitingBeginGeneration !== null;
     const projectedActive = state.turn.responding || state.turn.thinking;
     input.disabled = active;
+    attachBtn.disabled = active;
+    fileInput.disabled = active;
+    renderAttachments();
     sendBtn.disabled = active;
     sendBtn.hidden = projectedActive;
     cancelBtn.hidden = !projectedActive;
@@ -703,7 +833,7 @@ export function createStructuredConnection(
       input.style.overflowY = "hidden";
       input.style.height = `${Math.min(input.scrollHeight, 160)}px`;
       if (input.scrollHeight > 160) input.style.overflowY = "auto";
-    });
+    }, false, true);
   }
   input.addEventListener("input", () => {
     autoResize();
@@ -749,7 +879,9 @@ export function createStructuredConnection(
   composerForm.addEventListener("submit", (e) => {
     e.preventDefault();
     const text = input.value;
-    if (!text.trim() || input.disabled) return;
+    if ((!text.trim() && attachments.length === 0) || input.disabled) return;
+    const submittedAttachments = attachments;
+    uploading = submittedAttachments.length > 0;
     const generation = ++submissionGeneration;
     const submissionSocketGeneration = socketGeneration;
     awaitingBeginGeneration = generation;
@@ -759,13 +891,26 @@ export function createStructuredConnection(
     autoResize();
     clearError();
     renderComposerState();
-    sendStructuredPrompt(sessionId, text).then(
+    const send = async () => {
+      for (const attachment of submittedAttachments) {
+        if (disposed) return;
+        if (!attachment.path) attachment.path = (await uploadStructuredFile(sessionId, attachment.file)).path;
+      }
+      if (disposed) return;
+      const references = submittedAttachments.map(({ file, path }) =>
+        `Attached file ${JSON.stringify(file.name)}: ${JSON.stringify(path)}`);
+      await sendStructuredPrompt(sessionId, [text, ...references].filter(Boolean).join("\n\n"));
+    };
+    void send().then(
       () => {
-        if (
-          disposed
-          || generation !== submissionGeneration
-          || awaitingBeginGeneration !== generation
-        ) return;
+        if (disposed || generation !== submissionGeneration) return;
+        uploading = false;
+        if (attachments === submittedAttachments) {
+          attachments = [];
+          renderAttachments();
+        }
+        renderComposerState();
+        if (awaitingBeginGeneration !== generation) return;
         const acceptanceSocketGeneration = socketGeneration;
         acceptedSubmission = { generation, socketGeneration: acceptanceSocketGeneration };
         // A replacement socket may have captured idle before the POST claimed
@@ -773,6 +918,7 @@ export function createStructuredConnection(
         if (acceptanceSocketGeneration > submissionSocketGeneration) reconnectForReconciliation();
       },
       (e: unknown) => {
+        uploading = false;
         if (disposed || generation !== submissionGeneration) return;
         if (awaitingBeginGeneration === generation) awaitingBeginGeneration = null;
         if (input.value === "") {
@@ -912,6 +1058,7 @@ export function createStructuredConnection(
       pendingScroll = {
         top: parkedScrollTop ?? scrollEl.scrollTop,
         follow: followingBottom,
+        smooth: false,
       };
       parkedScrollTop = null;
       finishTranscriptLayout();
@@ -927,6 +1074,7 @@ export function createStructuredConnection(
       parkedScrollTop = pendingScroll?.top ?? scrollEl.scrollTop;
       scrollWorkActive = false;
       cancelScrollFrame();
+      stopSmoothFollow();
       cancelFocusFrame();
     },
     focusTerminal() {
@@ -936,6 +1084,10 @@ export function createStructuredConnection(
       // No PTY behind a structured session — the leader's literal-byte
       // escape hatch has nothing to do here.
     },
+    updateInfo(next: AttachInfo) {
+      titleEl.innerHTML = paneTitleHtml(sessionId, next);
+      titleEl.title = paneTitleAttr(sessionId, next);
+    },
     dispose() {
       if (disposed) return;
       disposed = true;
@@ -943,6 +1095,7 @@ export function createStructuredConnection(
       mountToken++;
       scrollWorkActive = false;
       cancelScrollFrame();
+      stopSmoothFollow();
       cancelFocusFrame();
       cancelReconnect();
       closeCurrentSocket();
@@ -950,6 +1103,8 @@ export function createStructuredConnection(
       expandedGroupIds.clear();
       scrollEl.removeEventListener("scroll", onTranscriptScroll);
       scrollEl.removeEventListener("click", onTranscriptClick, true);
+      scrollEl.removeEventListener("wheel", stopSmoothFollow);
+      scrollEl.removeEventListener("touchstart", stopSmoothFollow);
       document.removeEventListener("pointerdown", closeConfigOnOutsidePress);
       el.remove();
     },

web/src/structuredRender.test.ts

@@ -40,10 +40,15 @@ describe("buildTranscriptRow: user/agent/thought", () => {
     expect(ps[0].innerHTML).toContain("<code>three</code>");
   });
 
-  it("renders a thought row as plain text", () => {
-    const el = buildTranscriptRow(row("agent_thought", { content: { type: "text", text: "hmm" } }));
+  it("trims ACP framing whitespace and renders thought-row inline markdown", () => {
+    const el = buildTranscriptRow(
+      row("agent_thought", {
+        content: { type: "text", text: "\n\n**Planning comply tool commentary update**\n" },
+      }),
+    );
     expect(el.className).toContain("st-row-thought");
-    expect(el.textContent).toBe("hmm");
+    expect(el.textContent).toBe("Planning comply tool commentary update");
+    expect(el.querySelector("strong")?.textContent).toBe("Planning comply tool commentary update");
   });
 
   it("falls back to a labelled placeholder for non-text content, never crashing", () => {
@@ -153,7 +158,10 @@ describe("buildTranscriptRow: tool calls", () => {
     expect(head.getAttribute("aria-expanded")).toBe("true");
     expect(out.textContent).toContain("match found");
     head.click();
-    expect(out.hidden).toBe(true);
+    expect(out.hidden).toBe(false);
+    expect(out.getAttribute("aria-hidden")).toBe("true");
+    expect(out.inert).toBe(true);
+    expect(out.classList.contains("is-expanded")).toBe(false);
   });
 
   it("does not expand when there is nothing to show", () => {
@@ -163,19 +171,107 @@ describe("buildTranscriptRow: tool calls", () => {
     expect(head.getAttribute("aria-expanded")).toBe("false");
   });
 
-  it("shows raw command, input, and output as separately copyable details", () => {
+  it("renders command fields and keeps the exact JSON available", () => {
     const el = buildTranscriptRow(
       row("tool_call", {
         title: "Bash(test)",
-        rawInput: { command: "printf ok", timeout_ms: 1000 },
-        rawOutput: { stdout: "ok", exit_code: 0 },
+        rawInput: { command: "printf ok", cwd: "/workspace", timeout_ms: 1000 },
+        rawOutput: { formatted_output: "ok", exit_code: 0 },
       }),
     );
     (el.querySelector(".st-tool-head") as HTMLButtonElement).click();
-    const labels = [...el.querySelectorAll(".st-tool-detail-label")].map((node) => node.textContent);
-    expect(labels).toEqual(["Command", "Input", "Output"]);
     expect(el.querySelector(".st-tool-detail pre")!.textContent).toBe("printf ok");
-    expect(el.querySelectorAll(".st-tool-detail pre[role=button]")).toHaveLength(3);
+    expect(el.querySelector(".st-tool-fact")!.textContent).toBe("Exit code0");
+    const raw = el.querySelector(".st-tool-raw") as HTMLDetailsElement;
+    expect(raw.open).toBe(false);
+    expect(raw.textContent).toContain('"timeout_ms": 1000');
+    expect(raw.textContent).toContain('"exit_code": 0');
+  });
+
+  it("renders MCP arguments and results without hiding the source payload", () => {
+    const el = buildTranscriptRow(
+      row("tool_call", {
+        title: "mcp.github.search",
+        rawInput: { server: "github", tool: "search", arguments: { query: "ACP" } },
+        rawOutput: { result: { count: 2 }, error: null },
+      }),
+    );
+    (el.querySelector(".st-tool-head") as HTMLButtonElement).click();
+    const labels = [
+      ...el.querySelectorAll(
+        ".st-tool-out > .st-disclosure-clip > .st-disclosure-inner > .st-tool-detail",
+      ),
+    ].map((node) => node.querySelector(".st-tool-detail-label")?.textContent);
+    expect(labels).toEqual(["Arguments", "Result"]);
+    expect(el.querySelector(".st-tool-raw")!.textContent).toContain('"server": "github"');
+  });
+
+  it("renders a recognized web search query", () => {
+    const el = buildTranscriptRow(
+      row("tool_call", {
+        title: "Search the web",
+        rawInput: { type: "webSearch", query: "Agent Client Protocol", action: { type: "search" } },
+      }),
+    );
+    (el.querySelector(".st-tool-head") as HTMLButtonElement).click();
+    expect(el.querySelector(".st-tool-detail-label")!.textContent).toBe("Query");
+    expect(el.querySelector(".st-tool-detail pre")!.textContent).toBe("Agent Client Protocol");
+  });
+
+  it("falls back to raw JSON for an unknown provider shape", () => {
+    const el = buildTranscriptRow(
+      row("tool_call", { title: "Custom", rawInput: { peculiar: [1, 2] }, rawOutput: "done" }),
+    );
+    (el.querySelector(".st-tool-head") as HTMLButtonElement).click();
+    expect(
+      el.querySelectorAll(
+        ".st-tool-out > .st-disclosure-clip > .st-disclosure-inner > .st-tool-detail",
+      ),
+    ).toHaveLength(0);
+    expect(el.querySelector(".st-tool-raw")!.textContent).toContain('"peculiar"');
+    expect(el.querySelector(".st-tool-raw")!.textContent).toContain('"done"');
+  });
+
+  it("renders standardized content before provider-specific and raw data", () => {
+    const el = buildTranscriptRow(
+      row("tool_call", {
+        title: "Bash(test)",
+        content: [
+          { type: "content", content: { type: "text", text: "typed result" } },
+          { type: "content", content: { type: "resource_link", name: "report", uri: "file:///tmp/report" } },
+          { type: "terminal", terminalId: "term-1" },
+        ],
+        rawInput: { command: "test" },
+        rawOutput: { formatted_output: "typed result", exit_code: 0 },
+      }),
+    );
+    (el.querySelector(".st-tool-head") as HTMLButtonElement).click();
+    const inner = el.querySelector(".st-tool-out > .st-disclosure-clip > .st-disclosure-inner")!;
+    expect([...inner.children].map((node) => node.className)).toEqual([
+      "st-tool-text st-copyable",
+      "st-tool-resource",
+      "st-tool-terminal",
+      "st-tool-detail",
+      "st-tool-fact",
+      "st-tool-raw",
+    ]);
+    expect(el.querySelector(".st-tool-resource")!.textContent).toContain("file:///tmp/report");
+    expect(el.querySelector(".st-tool-terminal")!.textContent).toBe("Terminal · term-1");
+  });
+
+  it("renders safe typed image and audio blocks as media controls", () => {
+    const el = buildTranscriptRow(
+      row("tool_call", {
+        title: "Media",
+        content: [
+          { type: "content", content: { type: "image", mimeType: "image/png", data: "aW1hZ2U=" } },
+          { type: "content", content: { type: "audio", mimeType: "audio/mpeg", data: "YXVkaW8=" } },
+        ],
+      }),
+    );
+    (el.querySelector(".st-tool-head") as HTMLButtonElement).click();
+    expect((el.querySelector(".st-tool-image") as HTMLImageElement).src).toBe("data:image/png;base64,aW1hZ2U=");
+    expect((el.querySelector(".st-tool-audio") as HTMLAudioElement).src).toBe("data:audio/mpeg;base64,YXVkaW8=");
   });
 });
 
@@ -191,9 +287,11 @@ describe("buildToolGroup", () => {
     const head = group.querySelector<HTMLButtonElement>(".st-tool-group-head")!;
     const body = group.querySelector<HTMLElement>(".st-tool-group-body")!;
     expect(head.textContent).toContain("2 tool calls");
-    expect(body.hidden).toBe(true);
+    expect(body.getAttribute("aria-hidden")).toBe("true");
+    expect(body.inert).toBe(true);
     head.click();
-    expect(body.hidden).toBe(false);
+    expect(body.getAttribute("aria-hidden")).toBe("false");
+    expect(body.classList.contains("is-expanded")).toBe(true);
     expect(onExpanded).toHaveBeenCalledWith(true);
     const toolHeads = group.querySelectorAll<HTMLButtonElement>(".st-tool-head");
     toolHeads[1].click();

web/src/structuredRender.ts

@@ -196,20 +196,21 @@ function makeCopyable(node: HTMLElement, text: string, label: string): void {
 function buildContentRow(row: TranscriptRow, variant: "user" | "agent" | "thought"): HTMLElement {
   const data = row.data as { content?: AcpContentBlock; messageId?: string } | undefined;
   const text = contentBlockText(data?.content);
+  const displayText = variant === "thought" ? text.trim() : text;
   const wrap = el("div", `st-row st-row-${variant}`);
   const body = el("div", "st-body");
   if (variant === "user") {
     const line = el("div", "st-user-text");
-    line.textContent = text;
+    line.textContent = displayText;
     body.appendChild(line);
   } else if (variant === "agent") {
-    renderProse(body, text);
+    renderProse(body, displayText);
   } else {
-    body.textContent = text;
+    body.innerHTML = renderInlineMarkdown(displayText);
   }
   wrap.appendChild(body);
   const label = variant === "user" ? "message" : variant === "agent" ? "response" : "thought";
-  makeCopyable(wrap, text, label);
+  makeCopyable(wrap, displayText, label);
   return wrap;
 }
 
@@ -245,16 +246,18 @@ function printable(value: unknown): string | null {
   }
 }
 
-function toolInput(tool: AcpToolCallLike): { command: string | null; input: string | null } {
-  const raw = tool.rawInput;
-  if (!raw || typeof raw !== "object" || Array.isArray(raw)) {
-    return { command: null, input: printable(raw) };
+function jsonPrintable(value: unknown): string | null {
+  if (value === undefined) return null;
+  try {
+    return JSON.stringify(value, null, 2) ?? null;
+  } catch {
+    return printable(value);
   }
-  const record = raw as Record<string, unknown>;
-  const command = typeof record.command === "string" ? record.command : null;
-  if (!command) return { command: null, input: printable(raw) };
-  const rest = Object.fromEntries(Object.entries(record).filter(([key]) => key !== "command"));
-  return { command, input: Object.keys(rest).length > 0 ? printable(rest) : null };
+}
+
+function record(value: unknown): Record<string, unknown> | null {
+  if (!value || typeof value !== "object" || Array.isArray(value)) return null;
+  return value as Record<string, unknown>;
 }
 
 function appendToolDetail(container: HTMLElement, label: string, text: string): void {
@@ -268,6 +271,213 @@ function appendToolDetail(container: HTMLElement, label: string, text: string):
   container.appendChild(detail);
 }
 
+function appendToolValue(container: HTMLElement, label: string, value: unknown, duplicates?: Set<string>): void {
+  const text = printable(value);
+  if (text !== null && text !== "" && !duplicates?.has(text)) appendToolDetail(container, label, text);
+}
+
+function appendExitCode(container: HTMLElement, value: unknown): void {
+  if (typeof value !== "number") return;
+  const line = el("div", "st-tool-fact");
+  const label = el("span", "st-tool-fact-label");
+  label.textContent = "Exit code";
+  const code = el("code", value === 0 ? "st-tool-exit-ok" : "st-tool-exit-failed");
+  code.textContent = String(value);
+  line.append(label, code);
+  container.appendChild(line);
+}
+
+function appendCommandPayload(
+  container: HTMLElement,
+  input: Record<string, unknown>,
+  output: unknown,
+  contentText: Set<string>,
+): boolean {
+  if (typeof input.command !== "string") return false;
+  appendToolDetail(container, "Command", input.command);
+  appendToolValue(container, "Working directory", input.cwd);
+
+  const result = record(output);
+  if (result) {
+    appendToolValue(container, "Output", result.formatted_output ?? result.stdout ?? result.output, contentText);
+    appendExitCode(container, result.exit_code);
+  }
+  return true;
+}
+
+function appendMcpPayload(
+  container: HTMLElement,
+  input: Record<string, unknown>,
+  output: unknown,
+  contentText: Set<string>,
+): boolean {
+  if (typeof input.server !== "string" || typeof input.tool !== "string" || !("arguments" in input)) return false;
+  appendToolValue(container, "Arguments", input.arguments);
+  const result = record(output);
+  if (result) {
+    appendToolValue(container, "Result", result.result, contentText);
+    appendToolValue(container, "Error", result.error);
+  }
+  return true;
+}
+
+function appendSearchPayload(
+  container: HTMLElement,
+  input: Record<string, unknown>,
+  tool: AcpToolCallLike,
+): boolean {
+  if (typeof input.query !== "string" || (tool.kind !== "search" && input.type !== "webSearch")) return false;
+  appendToolDetail(container, "Query", input.query);
+  appendToolValue(container, "Action", input.action);
+  return true;
+}
+
+function appendFunctionPayload(
+  container: HTMLElement,
+  input: Record<string, unknown>,
+  output: unknown,
+  contentText: Set<string>,
+): boolean {
+  if (!("arguments" in input)) return false;
+  appendToolValue(container, "Arguments", input.arguments);
+  const result = record(output);
+  if (result) appendToolValue(container, "Result", result.output, contentText);
+  return true;
+}
+
+function appendKnownToolPayload(
+  container: HTMLElement,
+  tool: AcpToolCallLike,
+  content: AcpToolCallContent[],
+): void {
+  const input = record(tool.rawInput);
+  if (!input) return;
+  const contentText = new Set(
+    content
+      .filter((block): block is Extract<AcpToolCallContent, { type: "content" }> => block.type === "content")
+      .filter((block) => block.content.type === "text")
+      .map((block) => (block.content as Extract<AcpContentBlock, { type: "text" }>).text),
+  );
+  if (appendCommandPayload(container, input, tool.rawOutput, contentText)) return;
+  if (appendMcpPayload(container, input, tool.rawOutput, contentText)) return;
+  if (appendSearchPayload(container, input, tool)) return;
+  appendFunctionPayload(container, input, tool.rawOutput, contentText);
+}
+
+function safeMediaSource(
+  mimeType: string | undefined,
+  data: string | undefined,
+  family: "image" | "audio",
+): string | null {
+  if (!mimeType || !data || !new RegExp(`^${family}/[a-z0-9.+-]+$`, "i").test(mimeType)) return null;
+  return `data:${mimeType};base64,${data}`;
+}
+
+function appendContentBlock(container: HTMLElement, block: AcpContentBlock): void {
+  if (block.type === "text") {
+    if (!block.text) return;
+    const text = el("div", "st-tool-text");
+    text.textContent = block.text;
+    makeCopyable(text, block.text, "output");
+    container.appendChild(text);
+    return;
+  }
+  if (block.type === "image") {
+    const source = safeMediaSource(block.mimeType, block.data, "image");
+    if (source) {
+      const image = document.createElement("img");
+      image.className = "st-tool-image";
+      image.src = source;
+      image.alt = "Tool output";
+      image.loading = "lazy";
+      container.appendChild(image);
+      return;
+    }
+    appendToolValue(container, "Image", block.uri ?? block.mimeType ?? "Unavailable");
+    return;
+  }
+  if (block.type === "audio") {
+    const source = safeMediaSource(block.mimeType, block.data, "audio");
+    if (source) {
+      const audio = document.createElement("audio");
+      audio.className = "st-tool-audio";
+      audio.controls = true;
+      audio.src = source;
+      container.appendChild(audio);
+      return;
+    }
+    appendToolValue(container, "Audio", block.mimeType ?? "Unavailable");
+    return;
+  }
+  if (block.type === "resource_link") {
+    const resource = el("div", "st-tool-resource");
+    const name = el("span", "st-tool-resource-name");
+    name.textContent = block.title ?? block.name ?? "Resource";
+    resource.appendChild(name);
+    if (block.uri) {
+      const uri = el("code", "st-tool-resource-uri");
+      uri.textContent = block.uri;
+      makeCopyable(uri, block.uri, "resource URI");
+      resource.appendChild(uri);
+    }
+    if (block.description) {
+      const description = el("span", "st-tool-resource-description");
+      description.textContent = block.description;
+      resource.appendChild(description);
+    }
+    container.appendChild(resource);
+    return;
+  }
+  const resource = block.resource;
+  if (typeof resource?.text === "string") {
+    appendToolDetail(container, resource.uri ? `Resource · ${resource.uri}` : "Resource", resource.text);
+  } else {
+    appendToolValue(container, "Resource", resource);
+  }
+}
+
+function appendStandardContent(container: HTMLElement, content: AcpToolCallContent[]): void {
+  for (const block of content) {
+    if (block.type === "content") appendContentBlock(container, block.content);
+    if (block.type === "diff") container.appendChild(buildDiffBlock(block));
+    if (block.type === "terminal") {
+      const note = el("div", "st-tool-terminal");
+      note.textContent = block.terminalId ? `Terminal · ${block.terminalId}` : "Embedded terminal";
+      container.appendChild(note);
+    }
+  }
+}
+
+function appendRawPayload(container: HTMLElement, tool: AcpToolCallLike): void {
+  const input = jsonPrintable(tool.rawInput);
+  const output = jsonPrintable(tool.rawOutput);
+  if (input === null && output === null) return;
+
+  const disclosure = document.createElement("details");
+  disclosure.className = "st-tool-raw";
+  const summary = document.createElement("summary");
+  summary.textContent = "Raw JSON";
+  disclosure.appendChild(summary);
+  const body = el("div", "st-tool-raw-body");
+  if (input !== null) appendToolDetail(body, "Input", input);
+  if (output !== null) appendToolDetail(body, "Output", output);
+  disclosure.appendChild(body);
+  container.appendChild(disclosure);
+}
+
+function setDisclosure(element: HTMLElement, expanded: boolean, animate = false): void {
+  element.hidden = false;
+  if (animate && expanded && !element.classList.contains("is-expanded")) {
+    // Establish the collapsed grid track before opening it in the same event
+    // turn. Without this read, a freshly lazy-built tool body has no painted
+    // starting state and the browser quite reasonably skips the transition.
+    void element.offsetHeight;
+  }
+  element.classList.toggle("is-expanded", expanded);
+  element.setAttribute("aria-hidden", String(!expanded));
+  element.inert = !expanded;
+}
+
 /** `+added -removed` across every diff block in a tool call's content —
  *  real derived data, never a fabricated duration. */
 function toolDiffMeta(content: AcpToolCallContent[]): string {
@@ -330,48 +540,34 @@ function buildToolRow(
   }
   card.appendChild(head);
 
-  const out = el("div", "st-tool-out");
+  const out = el("div", "st-tool-out st-disclosure");
+  const outClip = el("div", "st-disclosure-clip");
+  const outInner = el("div", "st-disclosure-inner");
+  outClip.appendChild(outInner);
+  out.appendChild(outClip);
   out.hidden = true;
   let outBuilt = false;
   const buildOut = () => {
     if (outBuilt) return;
     outBuilt = true;
-    const { command, input } = toolInput(tool);
-    if (command) appendToolDetail(out, "Command", command);
-    if (input !== null) appendToolDetail(out, "Input", input);
-    const rawOutput = printable(tool.rawOutput);
-    if (rawOutput !== null) appendToolDetail(out, "Output", rawOutput);
-    const texts = content
-      .filter((c): c is Extract<AcpToolCallContent, { type: "content" }> => c.type === "content")
-      .map((c) => contentBlockText(c.content))
-      .filter(Boolean);
-    const contentText = texts.join("\n");
-    if (contentText && contentText !== rawOutput) {
-      const textPanel = el("div", "st-tool-text");
-      textPanel.textContent = contentText;
-      makeCopyable(textPanel, contentText, "output");
-      out.appendChild(textPanel);
-    }
-    for (const block of content) {
-      if (block.type === "diff") out.appendChild(buildDiffBlock(block));
-      if (block.type === "terminal") {
-        const note = el("div", "st-tool-text");
-        note.textContent = "[embedded terminal]";
-        out.appendChild(note);
-      }
-    }
-    if (out.children.length === 0) out.hidden = true;
+    appendStandardContent(outInner, content);
+    appendKnownToolPayload(outInner, tool, content);
+    appendRawPayload(outInner, tool);
   };
   card.appendChild(out);
 
-  const setExpanded = (nextExpanded: boolean) => {
+  const setExpanded = (nextExpanded: boolean, animate = false) => {
     if (nextExpanded) buildOut();
-    if (out.children.length === 0) nextExpanded = false;
+    if (outInner.children.length === 0) nextExpanded = false;
     head.setAttribute("aria-expanded", String(nextExpanded));
-    out.hidden = !nextExpanded;
+    if (outInner.children.length === 0) {
+      out.hidden = true;
+    } else {
+      setDisclosure(out, nextExpanded, animate);
+    }
   };
   head.addEventListener("click", () => {
-    setExpanded(head.getAttribute("aria-expanded") !== "true");
+    setExpanded(head.getAttribute("aria-expanded") !== "true", true);
     onExpandedChange?.(head.getAttribute("aria-expanded") === "true");
   });
   setExpanded(expanded);
@@ -407,13 +603,17 @@ export function buildToolGroup(
     .join(" · ");
   head.append(glyph, title, names);
 
-  const body = el("div", "st-tool-group-body");
-  body.hidden = !expanded;
-  body.append(...children);
+  const body = el("div", "st-tool-group-body st-disclosure");
+  const bodyClip = el("div", "st-disclosure-clip");
+  const bodyInner = el("div", "st-disclosure-inner");
+  bodyInner.append(...children);
+  bodyClip.appendChild(bodyInner);
+  body.appendChild(bodyClip);
+  setDisclosure(body, expanded);
   head.addEventListener("click", () => {
     expanded = !expanded;
     head.setAttribute("aria-expanded", String(expanded));
-    body.hidden = !expanded;
+    setDisclosure(body, expanded, true);
     onExpandedChange?.(expanded);
   });
   wrap.append(head, body);

web/src/styles.css

@@ -2533,7 +2533,7 @@ input.leaf-rename:focus {
 }
 
 .st-copyable::after {
-  content: "copy";
+  content: none;
   position: absolute;
   top: var(--sp-1);
   right: var(--sp-1);
@@ -2549,27 +2549,30 @@ input.leaf-rename:focus {
   transition: opacity var(--dur-fast) var(--ease-out);
 }
 
-.st-copyable:hover,
 .st-copyable:focus-visible {
   background: var(--surface-2);
   outline: none;
 }
 
-.st-copyable:hover::after,
-.st-copyable:focus-visible::after,
-.st-copyable[data-copy-state="copied"]::after,
-.st-copyable[data-copy-state="error"]::after {
-  opacity: 1;
-}
+@media (hover: hover) {
+  .st-copyable:hover {
+    background: var(--surface-2);
+  }
 
-.st-copyable[data-copy-state="copied"]::after {
-  content: "copied";
-  color: var(--live);
-}
+  .st-copyable:hover::after {
+    content: "copy";
+    opacity: 1;
+  }
 
-.st-copyable[data-copy-state="error"]::after {
-  content: "copy failed";
-  color: var(--danger);
+  .st-copyable[data-copy-state="copied"]:hover::after {
+    content: "copied";
+    color: var(--live);
+  }
+
+  .st-copyable[data-copy-state="error"]:hover::after {
+    content: "copy failed";
+    color: var(--danger);
+  }
 }
 
 /* tool rows: bordered, compact, deliberately not lifted */
@@ -2593,6 +2596,7 @@ input.leaf-rename:focus {
   gap: var(--sp-2);
   padding: var(--sp-2) var(--sp-3);
   min-width: 0;
+  transition: background var(--dur-fast) var(--ease-out);
 }
 
 .st-tool-head:hover {
@@ -2642,11 +2646,38 @@ input.leaf-rename:focus {
 }
 
 .st-tool-out {
-  border-top: 1px solid var(--border);
-  padding: var(--sp-2) var(--sp-3);
+  border-top: 1px solid transparent;
+}
+
+.st-disclosure {
+  display: grid;
+  grid-template-rows: 0fr;
+  opacity: 0;
+  transition:
+    grid-template-rows var(--dur) var(--ease-out),
+    opacity var(--dur-fast) var(--ease-out),
+    border-color var(--dur-fast) var(--ease-out);
+}
+
+.st-disclosure.is-expanded {
+  grid-template-rows: 1fr;
+  opacity: 1;
+}
+
+.st-disclosure-clip {
+  min-height: 0;
+  overflow: hidden;
+}
+
+.st-tool-out.is-expanded {
+  border-top-color: var(--border);
+}
+
+.st-tool-out .st-disclosure-inner {
   display: flex;
   flex-direction: column;
   gap: var(--sp-2);
+  padding: var(--sp-2) var(--sp-3);
 }
 
 /* `display: flex` above outranks the UA sheet's `[hidden]` (same pitfall as
@@ -2689,6 +2720,109 @@ input.leaf-rename:focus {
   overflow-x: auto;
 }
 
+.st-tool-fact {
+  display: flex;
+  align-items: baseline;
+  gap: var(--sp-2);
+  color: var(--faint);
+  font-size: var(--fs-11);
+}
+
+.st-tool-fact code {
+  font-family: var(--font-mono);
+  font-variant-numeric: tabular-nums;
+}
+
+.st-tool-exit-ok {
+  color: var(--live);
+}
+
+.st-tool-exit-failed {
+  color: var(--danger);
+}
+
+.st-tool-image {
+  display: block;
+  width: auto;
+  max-width: min(100%, 720px);
+  max-height: 480px;
+  border: 1px solid var(--border);
+  border-radius: var(--r-1);
+  object-fit: contain;
+}
+
+.st-tool-audio {
+  display: block;
+  width: min(100%, 480px);
+  min-height: var(--control-h);
+}
+
+.st-tool-resource {
+  display: grid;
+  grid-template-columns: auto minmax(0, 1fr);
+  align-items: baseline;
+  gap: var(--sp-1) var(--sp-2);
+  min-width: 0;
+  padding: var(--sp-2);
+  border: 1px solid var(--border);
+  border-radius: var(--r-1);
+  background: var(--bg);
+  font-size: var(--fs-12);
+}
+
+.st-tool-resource-name {
+  color: var(--ink);
+  font-weight: 500;
+}
+
+.st-tool-resource-uri {
+  min-width: 0;
+  overflow-wrap: anywhere;
+  color: var(--muted);
+}
+
+.st-tool-resource-description {
+  grid-column: 1 / -1;
+  color: var(--muted);
+}
+
+.st-tool-terminal {
+  color: var(--muted);
+  font-family: var(--font-mono);
+  font-size: var(--fs-12);
+}
+
+.st-tool-raw {
+  color: var(--faint);
+  font-size: var(--fs-11);
+}
+
+.st-tool-raw summary {
+  width: fit-content;
+  padding-block: var(--sp-1);
+  cursor: pointer;
+  user-select: none;
+  transition: color var(--dur-fast) var(--ease-out);
+}
+
+.st-tool-raw summary:hover,
+.st-tool-raw summary:focus-visible {
+  color: var(--ink);
+}
+
+.st-tool-raw summary:focus-visible {
+  border-radius: var(--r-1);
+  outline: 2px solid var(--accent-ring);
+  outline-offset: 2px;
+}
+
+.st-tool-raw-body {
+  display: flex;
+  flex-direction: column;
+  gap: var(--sp-2);
+  padding-top: var(--sp-1);
+}
+
 .st-tool-group {
   min-width: 0;
   border: 1px solid var(--border);
@@ -2715,6 +2849,7 @@ input.leaf-rename:focus {
   gap: var(--sp-2);
   padding: 0;
   min-width: 0;
+  transition: color var(--dur-fast) var(--ease-out);
 }
 
 .st-tool-group-head:hover {
@@ -2745,12 +2880,16 @@ input.leaf-rename:focus {
 }
 
 .st-tool-group-body {
-  padding-top: var(--sp-2);
-  display: flex;
-  flex-direction: column;
+  padding-top: 0;
 }
 
-.st-tool-group-body > .st-row-tool {
+.st-tool-group-body .st-disclosure-inner {
+  display: flex;
+  flex-direction: column;
+  padding-top: var(--sp-2);
+}
+
+.st-tool-group-body .st-disclosure-inner > .st-row-tool {
   padding: var(--sp-1) 0;
 }
 
@@ -2758,6 +2897,21 @@ input.leaf-rename:focus {
   display: none;
 }
 
+/* Live transcript rows resolve into the stream through a short occlusion,
+   matching data becoming concrete without replaying on token patches. */
+.st-row-enter {
+  animation: structured-row-enter var(--dur) var(--ease-out) both;
+}
+
+@keyframes structured-row-enter {
+  from {
+    opacity: 0.2;
+    transform: translateY(3px);
+    clip-path: inset(0 0 18% 0);
+    filter: blur(1px);
+  }
+}
+
 .st-diff-block {
   display: flex;
   flex-direction: column;
@@ -2941,6 +3095,45 @@ input.leaf-rename:focus {
   min-width: 0;
 }
 
+.structured-attachments {
+  display: flex;
+  flex-wrap: wrap;
+  gap: var(--sp-1);
+  padding: var(--sp-1);
+}
+
+.structured-attachments[hidden] { display: none; }
+
+.structured-attachment {
+  display: inline-flex;
+  align-items: center;
+  min-width: 0;
+  max-width: 100%;
+  padding-left: var(--sp-2);
+  background: var(--surface-2);
+  border: 1px solid var(--border);
+  border-radius: var(--r-1);
+  font-size: var(--fs-11);
+}
+
+.structured-attachment > span {
+  overflow: hidden;
+  text-overflow: ellipsis;
+  white-space: nowrap;
+}
+
+.structured-attachment button {
+  flex-shrink: 0;
+  min-width: var(--tap);
+  min-height: var(--tap);
+  border: 0;
+  background: transparent;
+  color: var(--muted);
+}
+
+.structured-attachment button:hover { color: var(--ink); }
+.structured-attachment button:disabled { opacity: 0.5; }
+
 .structured-input {
   display: block;
   width: 100%;
@@ -3015,6 +3208,15 @@ input.leaf-rename:focus {
 }
 
 @media (max-width: 520px) {
+  .structured-composer {
+    margin: var(--sp-1) 0 0;
+    padding-bottom: calc(var(--sp-1) + env(safe-area-inset-bottom, 0px));
+    border-right: 0;
+    border-bottom: 0;
+    border-left: 0;
+    border-radius: var(--r-2) var(--r-2) 0 0;
+  }
+
   .structured-config-menu {
     right: calc(-1 * (var(--control-h) + var(--sp-2)));
   }
@@ -3117,18 +3319,18 @@ input.leaf-rename:focus {
   .act,
   .st-copyable,
   .st-copyable::after,
+  .st-disclosure,
+  .st-tool-head,
   .st-tool-group-glyph {
     transition-duration: 0.01ms;
   }
 
-  .structured-activity-pulse {
+  .st-row-enter {
     animation: none;
   }
-}
 
-@media (hover: none) {
-  .st-copyable::after {
-    opacity: 0.7;
+  .structured-activity-pulse {
+    animation: none;
   }
 }
 

web/src/types.ts

@@ -56,7 +56,7 @@ export interface Session {
    * how the command bar's empty query sorts a never-focused session after every
    * session that has one (`docs/COMMAND-BAR.md`). */
   last_focused_at?: IsoTimestamp | null;
-  /** The ACP session id the `claude-code-acp` adapter returned from
+  /** The ACP session id the selected provider adapter returned from
    * `session/new` (#134). Only a `Structured` session whose handshake
    * succeeded has one; a respawn passes it to `session/load` (#135). */
   acp_session_id?: string | null;
@@ -485,14 +485,28 @@ export type StructuredApprovalDecision = "allow_once" | "allow_for_session" | "d
 
 // ---- ACP v1 payload shapes (agent-client-protocol schema, camelCase) ----
 
-/** `ContentBlock`. Only `text` is common in practice; the rest degrade to a
- * generic placeholder rather than being dropped silently. */
+export interface AcpEmbeddedResource {
+  uri?: string;
+  mimeType?: string;
+  text?: string;
+  blob?: string;
+}
+
+/** `ContentBlock`, including the fields needed to render typed tool output. */
 export type AcpContentBlock =
   | { type: "text"; text: string }
-  | { type: "image"; mimeType?: string }
-  | { type: "audio"; mimeType?: string }
-  | { type: "resource_link"; uri?: string; name?: string }
-  | { type: "resource"; resource?: unknown };
+  | { type: "image"; data?: string; mimeType?: string; uri?: string | null }
+  | { type: "audio"; data?: string; mimeType?: string }
+  | {
+      type: "resource_link";
+      uri?: string;
+      name?: string;
+      title?: string | null;
+      description?: string | null;
+      mimeType?: string | null;
+      size?: number | null;
+    }
+  | { type: "resource"; resource?: AcpEmbeddedResource };
 
 /** `ContentChunk` — the payload of a `User`/`AgentText`/`AgentThought` row. */
 export interface AcpContentChunk {

web/tsconfig.build.json

@@ -0,0 +1,8 @@
+{
+  // The nix derivation's src is `./web`, so the shared fixtures/ directory at
+  // the repo root does not exist there and `*.test.ts` cannot resolve its
+  // imports. Tests are not part of the shipped bundle; `pnpm typecheck` still
+  // checks them from a full checkout.
+  "extends": "./tsconfig.json",
+  "exclude": ["src/**/*.test.ts", "src/**/*.test.tsx"]
+}