fix(maestro): deserialize unknown ActivityState variants as Idle

A newer daemon's unknown activity variant failed the whole Session
deserialization on older clients. Hand-written Deserialize maps any
unknown string to Idle; non-string values still error. (#110)

.gitea/workflows/ci.yml

@@ -97,3 +97,34 @@ jobs:
 
       - name: build
         run: pnpm -C web build
+
+  # The flake pins pnpmDeps.hash against web/pnpm-lock.yaml (#98). A lockfile
+  # change invalidates the pin silently elsewhere, so the packaged build has to
+  # fail here too.
+  flake:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+
+      # The runner container is root with no `nixbld` group, but the installer
+      # writes `build-users-group = nixbld` anyway and then fails on it, so the
+      # config goes in first. Flakes are off by default and `nix build .#…`
+      # needs them. Written again afterwards in case the installer replaced it.
+      - name: Install nix
+        run: |
+          mkdir -p /etc/nix
+          printf 'build-users-group =\nexperimental-features = nix-command flakes\n' > /etc/nix/nix.conf
+          curl -fsSL https://nixos.org/nix/install | sh -s -- --no-daemon --yes
+          printf 'build-users-group =\nexperimental-features = nix-command flakes\n' > /etc/nix/nix.conf
+          echo "$HOME/.nix-profile/bin" >> "$GITHUB_PATH"
+
+      # The installer does not enable flakes, so `nix build .#…` needs the
+      # features passed explicitly — a local machine that has them in
+      # nix.conf will build fine while CI fails without this.
+      - name: build flake packages
+        run: |
+          nix --extra-experimental-features "nix-command flakes" build \
+            .#webFrontend \
+            .#maestro \
+            .#maestro-web \
+            --no-link

CLAUDE.md

@@ -66,6 +66,10 @@ See `docs/INSTALL.md` for end-user install instructions.
 collisions, what blocks a kill, what `--force` retains, and what reclaim
 touches. Read it before changing anything that creates or removes one.
 
+`docs/SIDEBAR.md` is the contract for session cards in the web and TUI
+sidebars — line layout, activity colours, duration format, state precedence.
+Read it before changing sidebar rendering.
+
 `nix run .#dev` (or `just dev`) brings up the whole local stack under
 process-compose: a debug daemon on 127.0.0.1:7071, then Vite on :5173 once the
 daemon answers `/api/info`. The SPA proxies `/api/*` back to the daemon, so only

crates/maestro-cli/src/cli.rs

@@ -102,11 +102,6 @@ pub struct SpawnArgs {
     /// there.
     #[arg(long)]
     pub existing_branch: bool,
-    /// Remove the worktree when the session is killed. Kept for wire
-    /// compatibility (#56): the daemon now always cleans up on kill, guarded
-    /// against unsaved work.
-    #[arg(long, default_value_t = true)]
-    pub cleanup_on_kill: bool,
     /// After spawning, attach immediately.
     #[arg(long, short = 'a')]
     pub attach: bool,
@@ -125,6 +120,11 @@ pub struct AttachArgs {
 pub struct KillArgs {
     /// Session ID to kill.
     pub session_id: Uuid,
+    /// End the session even when its worktree holds unsaved work (#81). The
+    /// worktree is retained — never removed — and enters the retained store;
+    /// the output says where the work went.
+    #[arg(long)]
+    pub force: bool,
 }
 
 fn parse_kv(s: &str) -> Result<(String, String), String> {
@@ -163,7 +163,6 @@ mod tests {
             "/repos/foo",
             "--branch",
             "feat/x",
-            "--cleanup-on-kill",
             "-e",
             "FOO=bar",
             "-e",
@@ -174,7 +173,6 @@ mod tests {
             Command::Spawn(a) => {
                 assert_eq!(a.command, "bash");
                 assert_eq!(a.branch.as_deref(), Some("feat/x"));
-                assert!(a.cleanup_on_kill);
                 assert_eq!(
                     a.env,
                     vec![("FOO".into(), "bar".into()), ("BAZ".into(), "qux".into()),]
@@ -184,27 +182,6 @@ mod tests {
         }
     }
 
-    #[test]
-    fn cleanup_on_kill_defaults_true_for_the_wire() {
-        let cli = Cli::try_parse_from([
-            "maestro",
-            "spawn",
-            "--cwd",
-            "/tmp",
-            "--command",
-            "bash",
-            "--worktree-from",
-            "/repos/foo",
-            "--branch",
-            "feat/x",
-        ])
-        .unwrap();
-        match cli.command {
-            Command::Spawn(a) => assert!(a.cleanup_on_kill),
-            _ => panic!("wrong subcommand"),
-        }
-    }
-
     /// Review fix: without a flag the CLI always sent `create_branch: true`,
     /// so the daemon's existing-branch path was unreachable and spawning onto
     /// a branch that already existed just failed.
@@ -256,6 +233,32 @@ mod tests {
         }
     }
 
+    #[test]
+    fn parses_kill_with_force() {
+        let id = "01234567-89ab-cdef-0123-456789abcdef";
+        let cli = Cli::try_parse_from(["maestro", "kill", "--force", id]).unwrap();
+        match cli.command {
+            Command::Kill(a) => {
+                assert!(a.force);
+                assert_eq!(a.session_id.to_string(), id);
+            }
+            _ => panic!("wrong subcommand"),
+        }
+    }
+
+    #[test]
+    fn kill_force_defaults_false() {
+        let id = "01234567-89ab-cdef-0123-456789abcdef";
+        let cli = Cli::try_parse_from(["maestro", "kill", id]).unwrap();
+        match cli.command {
+            Command::Kill(a) => {
+                assert!(!a.force);
+                assert_eq!(a.session_id.to_string(), id);
+            }
+            _ => panic!("wrong subcommand"),
+        }
+    }
+
     #[test]
     fn rejects_env_without_equals() {
         let err = Cli::try_parse_from([

crates/maestro-cli/src/dispatch.rs

@@ -62,8 +62,20 @@ pub async fn dispatch(
             run_attach_url(&daemon.attach_url(args.session_id)?, detach).await?;
         }
         Command::Kill(args) => {
-            run_kill(&daemon, &args).await?;
+            // #83: warn BEFORE the attempt, so the refusal is not a surprise.
+            // Best-effort: an unreachable list must not block the kill.
+            if !args.force {
+                warn_if_blocked(&daemon, args.session_id).await;
+            }
+            let outcome = run_kill(&daemon, &args).await?;
             println!("killed {}", args.session_id);
+            if let Some(w) = outcome.retained {
+                println!(
+                    "worktree retained at {} (branch {}, force-killed)",
+                    w.path.display(),
+                    w.branch
+                );
+            }
         }
         Command::Worktrees(args) => match args.command {
             WorktreesCommand::List(list_args) => {
@@ -92,6 +104,25 @@ pub async fn dispatch(
 /// Default detach byte, matching `maestro attach --detach-key`'s `^q`.
 const CTRL_Q: u8 = 0x11;
 
+/// #83: say "this will be refused" before the operator commits to it, in the
+/// same words [`maestro_protocol::InTheWay`] uses everywhere else.
+async fn warn_if_blocked(daemon: &DaemonClient, id: uuid::Uuid) {
+    let Ok(sessions) = daemon.list_sessions().await else {
+        return;
+    };
+    if let Some(b) = sessions
+        .iter()
+        .find(|s| s.id == id)
+        .and_then(|s| s.blocked_work)
+    {
+        if !b.is_clear() {
+            eprintln!(
+                "warning: this kill will be refused — the session's worktree holds unsaved work ({b}); use --force to retain it"
+            );
+        }
+    }
+}
+
 /// HTTP client pointed at the daemon's API. That surface needs no auth —
 /// reaching `bind_addr` is the authorization.
 #[allow(clippy::result_large_err)]

crates/maestro-cli/src/sessions.rs

@@ -43,7 +43,6 @@ pub async fn run_spawn(client: &DaemonClient, args: SpawnArgs) -> Result<Session
         (Some(repo), Some(branch)) => Some(WorktreeSpec {
             base_repo: repo.clone(),
             branch: branch.clone(),
-            cleanup_on_kill: args.cleanup_on_kill,
             create_branch: !args.existing_branch,
         }),
         _ => None,
@@ -59,9 +58,14 @@ pub async fn run_spawn(client: &DaemonClient, args: SpawnArgs) -> Result<Session
     client.create_session(&body).await
 }
 
-/// `maestro kill`
-pub async fn run_kill(client: &DaemonClient, args: &KillArgs) -> Result<(), ClientError> {
-    client.kill_session(args.session_id).await
+/// `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.
+pub async fn run_kill(
+    client: &DaemonClient,
+    args: &KillArgs,
+) -> Result<maestro_protocol::KillOutcome, ClientError> {
+    client.kill_session(args.session_id, args.force).await
 }
 
 #[allow(clippy::write_literal)]
@@ -89,8 +93,8 @@ fn print_session_table(out: &mut impl Write, sessions: &[Session], info: &Daemon
     }
     writeln!(
         out,
-        "  {:<36}  {:<8}  {:<9}  {:<28}  {}",
-        "ID", "STATUS", "ACTIVITY", "DIR", "COMMAND"
+        "  {:<36}  {:<8}  {:<9}  {:<28}  {:<40}  {}",
+        "ID", "STATUS", "ACTIVITY", "DIR", "COMMAND", "BLOCKED"
     )
     .ok();
     for s in sorted {
@@ -104,6 +108,7 @@ fn print_session_table(out: &mut impl Write, sessions: &[Session], info: &Daemon
             ActivityState::Active => "active",
             ActivityState::Idle => "idle",
             ActivityState::AwaitingInput => "awaiting",
+            ActivityState::Error => "error",
         };
         // Show the live foreground command alongside the spawn command when
         // the daemon has observed one that differs (NAP-340).
@@ -111,15 +116,28 @@ fn print_session_table(out: &mut impl Write, sessions: &[Session], info: &Daemon
             Some(fg) if fg != &s.command => format!("{} [{}]", s.command, fg),
             _ => s.command.clone(),
         };
+        // #83: what an unforced kill would be refused for, in InTheWay's own
+        // words; blank while nothing blocks (or hasn't been probed yet).
+        let blocked = blocked_label(s);
         writeln!(
             out,
-            "  {:<36}  {:<8}  {:<9}  {:<28}  {command}",
-            s.id, status, activity, dir
+            "  {:<36}  {:<8}  {:<9}  {:<28}  {:<40}  {blocked}",
+            s.id, status, activity, dir, command
         )
         .ok();
     }
 }
 
+/// The blocked-work indicator (#83), phrased by [`InTheWay`]'s `Display`.
+/// Empty unless something actually blocks — "no unsaved work" would just be
+/// noise on every row.
+pub(crate) fn blocked_label(s: &Session) -> String {
+    s.blocked_work
+        .filter(|b| !b.is_clear())
+        .map(|b| b.to_string())
+        .unwrap_or_default()
+}
+
 /// Render a path with the daemon's home dir collapsed to `~`. Mirrors the web
 /// UI's abbreviation so CLI and browser show the same directory shorthand.
 pub(crate) fn abbreviate_dir(path: &std::path::Path, home: &str) -> String {
@@ -159,7 +177,9 @@ mod tests {
             foreground: None,
             activity: Default::default(),
             last_activity_at: chrono::Utc::now(),
+            activity_since: chrono::Utc::now(),
             current_cwd: None,
+            blocked_work: None,
         }
     }
 
@@ -220,4 +240,37 @@ mod tests {
         super::print_session_table(&mut buf, &[], &info(""));
         assert_eq!(String::from_utf8(buf).unwrap(), "no sessions\n");
     }
+
+    /// #83: a blocked session shows what an unforced kill would be refused
+    /// for, in `InTheWay`'s own words; a clear or unprobed one shows nothing.
+    #[test]
+    fn shows_the_blocked_work_summary_only_when_something_blocks() {
+        use maestro_protocol::InTheWay;
+
+        let mut blocked = session("/tmp", "claude", 1);
+        blocked.blocked_work = Some(InTheWay {
+            uncommitted_files: 3,
+            unpushed_commits: 2,
+            ..InTheWay::default()
+        });
+        let mut clear = session("/tmp", "bash", 2);
+        clear.blocked_work = Some(InTheWay::default());
+        let unprobed = session("/tmp", "zsh", 3);
+
+        let mut buf = Vec::new();
+        super::print_session_table(&mut buf, &[blocked, clear, unprobed], &info(""));
+        let out = String::from_utf8(buf).unwrap();
+        assert!(
+            out.contains("3 uncommitted files, 2 unpushed commits"),
+            "{out}"
+        );
+        // Clear and unprobed rows stay blank in the BLOCKED column.
+        let lines: Vec<&str> = out.lines().collect();
+        let header = lines.iter().position(|l| l.contains("BLOCKED")).unwrap();
+        for line in &lines[header + 1..] {
+            if !line.contains("uncommitted files") {
+                assert!(!line.contains("unsaved work"), "{line}");
+            }
+        }
+    }
 }

crates/maestro-cli/tests/against_mock_daemon.rs

@@ -76,7 +76,7 @@ async fn killing_an_unknown_session_reports_the_daemon_reason() {
 
     let err = mock
         .client()
-        .kill_session(Uuid::new_v4())
+        .kill_session(Uuid::new_v4(), false)
         .await
         .expect_err("should fail");
 
@@ -102,6 +102,9 @@ async fn spawn_round_trips_through_the_daemon() {
     assert_eq!(created.command, "bash");
     assert_eq!(mock.session_count(), 1);
 
-    mock.client().kill_session(created.id).await.expect("kill");
+    mock.client()
+        .kill_session(created.id, false)
+        .await
+        .expect("kill");
     assert_eq!(mock.session_count(), 0);
 }

crates/maestro-daemon/src/cli.rs

@@ -56,6 +56,9 @@ async fn run(config_override: Option<PathBuf>) -> Result<(), Box<dyn Error>> {
         Some(p) => Tmux::new().with_tmpdir(p),
         None => Tmux::new(),
     };
+    let retained = std::sync::Arc::new(crate::retained_store::RetainedStore::new(
+        config.retained_worktree_dir(),
+    ));
     let manager = SessionManager::new_with_replay(
         std::sync::Arc::new(tmux),
         sidecar,
@@ -66,7 +69,13 @@ async fn run(config_override: Option<PathBuf>) -> Result<(), Box<dyn Error>> {
     .with_spawn_history(crate::spawn_history::SpawnHistory::new(
         config.spawn_history_path(),
         config.spawn_history_days,
-    ));
+    ))
+    // One store instance shared with the API handlers: forced kills (#81)
+    // record here, `GET /api/worktrees` (#80) reads back from here.
+    .with_retained_store((*retained).clone());
+    // Spawned sessions learn where to report back (#103). Derived from the
+    // configured bind address; set before any spawn can happen.
+    manager.set_daemon_url(format!("http://{}", config.bind_addr));
 
     let recovered = manager.recover().await?;
     tracing::info!(recovered, "adopted existing tmux sessions");
@@ -85,9 +94,7 @@ async fn run(config_override: Option<PathBuf>) -> Result<(), Box<dyn Error>> {
         config.home_dir.clone(),
         config.spawn_presets.clone(),
         projects,
-        std::sync::Arc::new(crate::retained_store::RetainedStore::new(
-            config.retained_worktree_dir(),
-        )),
+        retained,
     ));
 
     let listener = TcpListener::bind(config.bind_addr).await?;

crates/maestro-daemon/src/local_api.rs

@@ -101,6 +101,8 @@ fn session_error_status(code: &str) -> StatusCode {
         "invalid_env" => StatusCode::BAD_REQUEST,
         // A guard refusal is the daemon doing its job, not a failure (#79).
         "kill_guarded" => StatusCode::CONFLICT,
+        // The retention record failed before anything was torn down (#81).
+        "retain_failed" => StatusCode::INTERNAL_SERVER_ERROR,
         _ => StatusCode::BAD_GATEWAY,
     }
 }
@@ -179,9 +181,29 @@ async fn create_session(
 /// The full error info is passed through rather than rebuilt from
 /// code + message: a `kill_guarded` refusal (#79) carries the unsaved-work
 /// breakdown clients render as "3 uncommitted files, 2 unpushed commits".
-async fn kill_session(State(s): State<LocalApiState>, Path(id): Path<Uuid>) -> Response {
-    match s.manager.kill(id).await {
-        Ok(()) => StatusCode::NO_CONTENT.into_response(),
+///
+/// With `force=true` (#81) the refusal is overridden and the worktree
+/// retained; the answer is `200` with a [`KillOutcome`] naming what was kept.
+/// Without it the historical `204` stands.
+#[derive(Debug, Deserialize)]
+struct KillQuery {
+    #[serde(default)]
+    force: bool,
+}
+
+async fn kill_session(
+    State(s): State<LocalApiState>,
+    Path(id): Path<Uuid>,
+    Query(q): Query<KillQuery>,
+) -> Response {
+    match s.manager.kill(id, q.force).await {
+        Ok(outcome) => {
+            if q.force {
+                (StatusCode::OK, Json(outcome)).into_response()
+            } else {
+                StatusCode::NO_CONTENT.into_response()
+            }
+        }
         Err(e) => {
             let info = e.to_error_info();
             let status = session_error_status(&info.code);

crates/maestro-daemon/src/projects.rs

@@ -261,17 +261,13 @@ impl ProjectScanner {
     }
 
     /// Cached snapshot, rescanning (off-thread) when the TTL has lapsed.
+    /// Also the background timer's entry point: a tick inside the TTL is a
+    /// no-op (#75).
     pub async fn repos(&self) -> std::sync::Arc<Vec<DiscoveredRepo>> {
-        self.repos_inner(false).await
-    }
-
-    async fn repos_inner(&self, force: bool) -> std::sync::Arc<Vec<DiscoveredRepo>> {
         let mut cache = self.cache.lock().await;
-        if !force {
-            if let Some((at, repos)) = cache.as_ref() {
-                if at.elapsed() < self.ttl {
-                    return repos.clone();
-                }
+        if let Some((at, repos)) = cache.as_ref() {
+            if at.elapsed() < self.ttl {
+                return repos.clone();
             }
         }
         let roots = self.roots.clone();
@@ -287,11 +283,11 @@ impl ProjectScanner {
         repos
     }
 
-    /// Rescan now, ignoring the TTL. Called by the background timer — going
-    /// through `repos()` would hit the cache and make most ticks no-ops,
-    /// leaving requests to pay for the rescan instead (#54 review).
+    /// One background-refresh tick: rescan only if the cached snapshot has
+    /// passed its TTL (#75) — the timer used to bypass it and re-walk the
+    /// roots every [`REFRESH_INTERVAL`].
     async fn refresh(&self) {
-        self.repos_inner(true).await;
+        self.repos().await;
     }
 
     /// Spawn the slow background refresh task. Drop the returned handle to
@@ -544,6 +540,32 @@ mod tests {
         assert_eq!(fresh[0].name, "late");
     }
 
+    #[tokio::test]
+    async fn background_refresh_honours_the_ttl() {
+        let tmp = tempfile::tempdir().unwrap();
+        let mut scanner = ProjectScanner::new(
+            vec![tmp.path().to_path_buf()],
+            3,
+            PathBuf::from("/nonexistent"),
+        );
+
+        let empty = scanner.repos().await;
+        assert!(empty.is_empty());
+
+        make_repo(tmp.path(), "late");
+        // A background tick inside the TTL must not re-walk the filesystem:
+        // the new repo stays invisible until the cache expires.
+        scanner.refresh().await;
+        assert!(scanner.repos().await.is_empty());
+
+        // Once the TTL lapses, the next tick picks it up.
+        scanner.ttl = Duration::ZERO;
+        scanner.refresh().await;
+        let fresh = scanner.repos().await;
+        assert_eq!(fresh.len(), 1);
+        assert_eq!(fresh[0].name, "late");
+    }
+
     #[test]
     fn disabled_scanner_always_serves_empty() {
         let scanner = ProjectScanner::disabled();

crates/maestro-daemon/src/session.rs

@@ -12,8 +12,8 @@ use std::time::Duration;
 
 use chrono::Utc;
 use maestro_protocol::{
-    ActivityState, CatalogEvent, CreateSessionRequest, ErrorInfo, Session, SessionStatus,
-    WorktreeSpec,
+    ActivityState, CatalogEvent, CreateSessionRequest, ErrorInfo, KillOutcome, RetainedReason,
+    RetainedWorktree, Session, SessionStatus, WorktreeSpec,
 };
 use tokio::sync::{broadcast, Mutex};
 use uuid::Uuid;
@@ -33,6 +33,13 @@ pub const EVENTS_CAPACITY: usize = maestro_config::EVENTS_CAPACITY;
 /// How often the liveness watcher polls tmux for sessions that disappeared.
 pub const DEFAULT_LIVENESS_INTERVAL: Duration = Duration::from_secs(2);
 
+/// How often the liveness watcher re-probes worktrees for the blocked-work
+/// indicator (#83). Each probe costs three git subprocesses per session, so
+/// the pass rides the same tick as everything else but runs on a slower
+/// cadence: an indicator a few seconds stale still warns before the kill
+/// attempt, which is all #83 needs.
+pub const DEFAULT_BLOCKED_WORK_INTERVAL: Duration = Duration::from_secs(15);
+
 /// Per-session daemon-local bookkeeping that complements the public `Session`.
 #[derive(Debug)]
 pub struct SessionRecord {
@@ -44,6 +51,11 @@ pub struct SessionRecord {
     /// `base_repo` from the original `WorktreeSpec`. Needed because `git
     /// worktree remove` is invoked from the base repo.
     pub worktree_base_repo: Option<PathBuf>,
+    /// Branch the worktree was created for, recorded at spawn time so a
+    /// forced kill (#81) can name it in the retained store without asking
+    /// git. Sessions adopted from a sidecar have no branch on record and
+    /// fall back to a probe.
+    pub worktree_branch: Option<String>,
     pub bridge: PtyBridge,
 }
 
@@ -66,6 +78,11 @@ pub enum SessionError {
     /// so it stays the operator's handle on their own unfinished work.
     #[error("kill refused: the session's worktree holds unsaved work ({0})")]
     KillGuarded(maestro_protocol::InTheWay),
+    /// A forced kill (#81) records the retained worktree *before* tearing
+    /// anything down; if that write fails nothing was destroyed, and the
+    /// error says so rather than silently dropping unrecorded work.
+    #[error("could not record the retained worktree: {0}")]
+    RetainFailed(String),
 }
 
 impl SessionError {
@@ -78,6 +95,7 @@ impl SessionError {
             SessionError::NotFound(_) => "not_found",
             SessionError::InvalidEnv(_) => "invalid_env",
             SessionError::KillGuarded(_) => "kill_guarded",
+            SessionError::RetainFailed(_) => "retain_failed",
         };
         let unsaved_work = match self {
             SessionError::KillGuarded(b) => Some(*b),
@@ -110,6 +128,14 @@ struct Inner {
     /// `None` when not wired (tests, or before `with_spawn_history`); a present
     /// but disabled (`0`-day) history no-ops internally.
     spawn_history: Option<SpawnHistory>,
+    /// Retained-worktree store (#78). `None` when not wired (tests); a forced
+    /// kill (#81) without one fails rather than destroying unrecorded work.
+    retained: Option<crate::retained_store::RetainedStore>,
+    /// The daemon's own HTTP base URL (#103), exported to spawned sessions as
+    /// `MAESTRO_URL`. `None` when unknown — those sessions simply don't get
+    /// the variable. A mutex because the runner sets it after construction,
+    /// possibly while clones are already serving.
+    daemon_url: std::sync::Mutex<Option<String>>,
     sessions: Mutex<HashMap<Uuid, SessionRecord>>,
     events: broadcast::Sender<CatalogEvent>,
 }
@@ -148,6 +174,8 @@ impl SessionManager {
                 fifo_dir,
                 replay_bytes,
                 spawn_history: None,
+                retained: None,
+                daemon_url: std::sync::Mutex::new(None),
                 sessions: Mutex::new(HashMap::new()),
                 events,
             }),
@@ -170,6 +198,24 @@ impl SessionManager {
         self
     }
 
+    /// Attach the retained-worktree store (#78). A forced kill (#81) needs it
+    /// to record what it retained; without one, forcing a guarded kill fails
+    /// instead of destroying unrecorded work.
+    pub fn with_retained_store(mut self, store: crate::retained_store::RetainedStore) -> Self {
+        let inner = Arc::get_mut(&mut self.inner)
+            .expect("with_retained_store must be called before the SessionManager is cloned");
+        inner.retained = Some(store);
+        self
+    }
+
+    /// Set the daemon's own HTTP base URL (#103), exported to every session
+    /// spawned afterwards as `MAESTRO_URL`. Unlike the `with_*` builders this
+    /// is a plain setter: the daemon runner learns its bound address after
+    /// construction, and clones may already exist by then.
+    pub fn set_daemon_url(&self, url: String) {
+        *self.inner.daemon_url.lock().expect("daemon_url mutex") = Some(url);
+    }
+
     /// Recent working dirs for the spawn form's picker (#24), newest-first and
     /// deduped by dir. Empty when no history is wired or it's disabled.
     pub fn recent_dirs(&self) -> Vec<RecentDir> {
@@ -246,7 +292,11 @@ impl SessionManager {
                     self.inner.worktree_mgr.add_existing(base_repo, branch)
                 }
                 .map_err(SessionError::Worktree)?;
-                (path.clone(), Some(path), Some(base_repo.clone()))
+                // Record the repository, not whatever the request named: a
+                // spawn from inside a linked worktree passes that worktree as
+                // `base_repo`, and clients group sessions by this path (#99).
+                let repo = crate::worktree::main_checkout_of(base_repo);
+                (path.clone(), Some(path), Some(repo))
             }
             None => (req.cwd.clone(), None, None),
         };
@@ -268,7 +318,7 @@ impl SessionManager {
                     return Err(e.into());
                 }
             };
-        let session_env = match sanitize_env(&req.env) {
+        let mut session_env = match sanitize_env(&req.env) {
             Ok(env) => env,
             Err(e) => {
                 let _ = std::fs::remove_file(&fifo_path);
@@ -276,6 +326,19 @@ impl SessionManager {
                 return Err(e);
             }
         };
+        // Identity + reporting target for the in-session hook (#106). Ours
+        // win over whatever the request carried, so a client cannot spoof
+        // another session's identity (#103).
+        session_env.insert("MAESTRO_SESSION_ID".into(), id.to_string());
+        if let Some(url) = self
+            .inner
+            .daemon_url
+            .lock()
+            .expect("daemon_url mutex")
+            .clone()
+        {
+            session_env.insert("MAESTRO_URL".into(), url);
+        }
         let spawned = {
             let tmux = self.inner.tmux.clone();
             let cwd = effective_cwd.clone();
@@ -317,8 +380,12 @@ impl SessionManager {
             foreground: None,
             activity: ActivityState::Active,
             last_activity_at: Utc::now(),
+            activity_since: chrono::Utc::now(),
 
             current_cwd: None,
+            // The watcher fills this in on its first blocked-work pass; a
+            // fresh tree has nothing in the way anyway.
+            blocked_work: None,
         };
 
         if let Err(e) = self.inner.sidecar.write(&session) {
@@ -340,6 +407,7 @@ impl SessionManager {
                     fifo_path,
                     worktree_path,
                     worktree_base_repo,
+                    worktree_branch: req.worktree.as_ref().map(|w| w.branch.clone()),
                     bridge,
                 },
             );
@@ -391,11 +459,17 @@ impl SessionManager {
     /// work, so ending a session that still matters becomes a deliberate
     /// `--force`, which retains rather than destroys (WORKTREES.md).
     ///
+    /// With `force` (#81) the refusal — and nothing else — is overridden:
+    /// the session ends and the guarded worktree is retained into the store
+    /// with reason `force-killed`, never removed. The outcome names what was
+    /// kept so a client can say where the work went. A tree whose guard is
+    /// clear never needed the override; force removes it as usual.
+    ///
     /// This is also how an already-dead session is dismissed. tmux is only
     /// asked to kill something it still has — calling `kill-session` on a
     /// session tmux already lost fails, and that failure is not interesting.
-    pub async fn kill(&self, id: Uuid) -> Result<(), SessionError> {
-        let (worktree, alive) = {
+    pub async fn kill(&self, id: Uuid, force: bool) -> Result<KillOutcome, SessionError> {
+        let (worktree, alive, known_branch) = {
             let sessions = self.inner.sessions.lock().await;
             match sessions.get(&id) {
                 None => return Err(SessionError::NotFound(id)),
@@ -405,26 +479,48 @@ impl SessionManager {
                         .clone()
                         .zip(record.worktree_path.clone()),
                     record.session.status == SessionStatus::Running,
+                    record.worktree_branch.clone(),
                 ),
             }
         };
-        // The guard runs before anything is torn down: refusing must leave the
-        // session running, exactly as the operator left it.
-        if let Some((_, path)) = worktree {
-            let probe = tmux_blocking(move || crate::worktree_probe::in_the_way(&path))
-                .await
-                .map_err(|e| SessionError::Worktree(crate::worktree::WorktreeError::from(e)))?;
-            if !probe.is_clear() {
-                return Err(SessionError::KillGuarded(probe));
-            }
+        let probe = match &worktree {
+            Some(wt) => Some(probe_worktree(wt).await?),
+            None => None,
+        };
+        let guarded = probe.as_ref().is_some_and(|p| !p.is_clear());
+        if guarded && !force {
+            return Err(SessionError::KillGuarded(probe.expect("guarded ⇒ probed")));
         }
+
+        let mut retained = None;
+        if guarded {
+            let entry = record_retention(
+                &self.inner,
+                worktree.as_ref().expect("guarded ⇒ worktree"),
+                known_branch,
+                RetainedReason::ForceKilled,
+            )
+            .await?;
+            retained = Some((entry, probe.expect("guarded ⇒ probed")));
+        }
+
         let removed = {
             let mut sessions = self.inner.sessions.lock().await;
             sessions.remove(&id)
         };
         let record = removed.ok_or(SessionError::NotFound(id))?;
-        cleanup_record(&self.inner, id, record, alive).await;
-        Ok(())
+        cleanup_record(&self.inner, id, record, alive, retained.is_some()).await;
+        Ok(KillOutcome {
+            retained: retained.map(|(entry, in_the_way)| RetainedWorktree {
+                id: entry.id,
+                path: entry.path,
+                base_repo: entry.base_repo,
+                branch: entry.branch,
+                reason: entry.reason,
+                retained_at: entry.retained_at,
+                in_the_way,
+            }),
+        })
     }
 
     /// Spawn a background task that polls tmux every `interval` and reaps any
@@ -435,6 +531,17 @@ impl SessionManager {
     /// `SessionManager` clone is dropped — call this once from the daemon
     /// startup path after [`Self::recover`] has populated the map.
     pub fn start_liveness_watcher(&self, interval: Duration) {
+        self.start_liveness_watcher_with_blocked_work(interval, DEFAULT_BLOCKED_WORK_INTERVAL);
+    }
+
+    /// [`Self::start_liveness_watcher`] with the blocked-work cadence (#83)
+    /// made explicit. Tests pass a small `blocked_work_interval` to watch the
+    /// probe actually happen.
+    pub fn start_liveness_watcher_with_blocked_work(
+        &self,
+        interval: Duration,
+        blocked_work_interval: Duration,
+    ) {
         let weak = Arc::downgrade(&self.inner);
         tokio::spawn(async move {
             let mut ticker = tokio::time::interval(interval);
@@ -442,6 +549,9 @@ impl SessionManager {
             // first tick fires immediately — skip it so we don't reap before
             // the caller has a chance to create anything.
             ticker.tick().await;
+            // Start "due" so the first live tick probes: a recovered daemon
+            // should not wait a full interval to show what blocks.
+            let mut since_probe = blocked_work_interval;
             loop {
                 ticker.tick().await;
                 let Some(inner) = weak.upgrade() else {
@@ -451,6 +561,11 @@ impl SessionManager {
                 // Same tick, no new timer (NAP-340): refresh activity for the
                 // survivors and emit SessionUpdated on any transition.
                 run_activity_pass(&inner).await;
+                since_probe += interval;
+                if since_probe >= blocked_work_interval {
+                    since_probe = Duration::ZERO;
+                    run_blocked_work_pass(&inner).await;
+                }
             }
         });
     }
@@ -482,11 +597,16 @@ impl SessionManager {
                     status: SessionStatus::Running,
                     created_at: Utc::now(),
                     // Activity is unknown on adoption; the watcher fills it in.
+                    // #104: the restart also resets the activity clock to now —
+                    // accepted, since the daemon cannot know how long a
+                    // recovered session had already been sitting idle.
                     foreground: None,
                     activity: ActivityState::Idle,
                     last_activity_at: Utc::now(),
+                    activity_since: chrono::Utc::now(),
 
                     current_cwd: None,
+                    blocked_work: None,
                 },
             };
             let fifo_path = self.inner.fifo_dir.join(format!("{id}.fifo"));
@@ -511,6 +631,9 @@ impl SessionManager {
                     // directory blocks that branch forever (#54 review).
                     worktree_path: session.worktree.as_ref().map(|w| w.path.clone()),
                     worktree_base_repo: session.worktree.as_ref().map(|w| w.base_repo.clone()),
+                    // The sidecar carries no branch; a forced kill of a
+                    // recovered session probes git for it at retain time.
+                    worktree_branch: None,
                     bridge,
                 },
             );
@@ -587,6 +710,49 @@ where
         .expect("tmux blocking task panicked")
 }
 
+/// What would be lost if this session's worktree were removed right now.
+///
+/// The single [`crate::worktree_probe::in_the_way`] call site behind both
+/// endings of a session — the kill guard (#79) and the natural-exit
+/// classifier (#82) — so neither can grow its own answer. Runs on the
+/// blocking pool; callers invoke it before anything is torn down, because
+/// refusing (#79), recording a retention (#81) and classifying an exit (#82)
+/// must all see the tree as it stands.
+async fn probe_worktree(
+    (_, path): &(PathBuf, PathBuf),
+) -> Result<maestro_protocol::InTheWay, SessionError> {
+    let path = path.clone();
+    tmux_blocking(move || crate::worktree_probe::in_the_way(&path))
+        .await
+        .map_err(|e| SessionError::Worktree(crate::worktree::WorktreeError::from(e)))
+}
+
+/// Record a guarded worktree into the retained store with `reason`, BEFORE
+/// the caller tears anything down: a failed write then leaves every artifact
+/// untouched instead of destroying work nothing records anymore. Shared by
+/// the forced kill (`ForceKilled`, #81) and the natural exit
+/// (`ExitedWithUnsavedWork`, #82) so the two paths cannot drift apart.
+async fn record_retention(
+    inner: &Arc<Inner>,
+    (base_repo, path): &(PathBuf, PathBuf),
+    known_branch: Option<String>,
+    reason: RetainedReason,
+) -> Result<crate::retained_store::RetainedWorktreeRecord, SessionError> {
+    let store = inner
+        .retained
+        .clone()
+        .ok_or_else(|| SessionError::RetainFailed("no retained store is wired".into()))?;
+    // Sessions adopted from a sidecar carry no branch; ask the tree itself.
+    let branch = known_branch
+        .or_else(|| crate::worktree_probe::current_branch(path))
+        .unwrap_or_default();
+    let base_repo = base_repo.clone();
+    let path = path.clone();
+    tmux_blocking(move || store.retain(&path, &base_repo, &branch, reason))
+        .await
+        .map_err(|e| SessionError::RetainFailed(e.to_string()))
+}
+
 /// One pass of the liveness watcher: diff the in-memory session set against
 /// the tmux-reported one, and reap anything we still track but tmux has lost.
 async fn run_liveness_pass(inner: &Arc<Inner>) {
@@ -694,6 +860,12 @@ async fn run_activity_pass(inner: &Arc<Inner>) {
             {
                 None
             } else {
+                // #104: stamp only when the state itself changed — never on
+                // foreground/cwd-only diffs, and never every tick, or the
+                // sidebar's duration would reset continuously and read zero.
+                if rec.session.activity != activity {
+                    rec.session.activity_since = Utc::now();
+                }
                 rec.session.activity = activity;
                 rec.session.foreground = foreground;
                 rec.session.current_cwd = current_cwd;
@@ -709,18 +881,79 @@ async fn run_activity_pass(inner: &Arc<Inner>) {
     }
 }
 
+/// Refresh each running session's blocked-work indicator (#83): what its
+/// worktree holds right now that would block an unforced kill. Rides the
+/// liveness tick on its own (slower) cadence — see
+/// [`DEFAULT_BLOCKED_WORK_INTERVAL`] — because every probe is three git
+/// subprocesses per session.
+///
+/// Sessions without a worktree are filtered out BEFORE any probe: they can
+/// never block a kill, so their indicator must cost nothing at all. A failed
+/// probe keeps the previous value rather than clearing it — a transient git
+/// error must not read as "nothing blocks". Like the activity pass, this only
+/// emits `SessionUpdated` when the value actually changed.
+async fn run_blocked_work_pass(inner: &Arc<Inner>) {
+    let targets: Vec<(Uuid, (PathBuf, PathBuf))> = {
+        let sessions = inner.sessions.lock().await;
+        sessions
+            .iter()
+            .filter(|(_, r)| r.session.status == SessionStatus::Running)
+            .filter_map(|(id, r)| {
+                let wt = r.worktree_base_repo.clone().zip(r.worktree_path.clone())?;
+                Some((*id, wt))
+            })
+            .collect()
+    };
+    if targets.is_empty() {
+        return;
+    }
+
+    for (id, wt) in targets {
+        // The kill guard's own probe (#79), so the indicator can never
+        // disagree with what a kill attempt would find.
+        let breakdown = match probe_worktree(&wt).await {
+            Ok(breakdown) => breakdown,
+            Err(e) => {
+                tracing::debug!(%id, error = ?e, "blocked-work: probe failed; keeping previous value");
+                continue;
+            }
+        };
+        let updated = {
+            let mut sessions = inner.sessions.lock().await;
+            let Some(rec) = sessions.get_mut(&id) else {
+                continue;
+            };
+            if rec.session.blocked_work == Some(breakdown) {
+                None
+            } else {
+                rec.session.blocked_work = Some(breakdown);
+                Some(rec.session.clone())
+            }
+        };
+        if let Some(session) = updated {
+            let _ = inner.events.send(CatalogEvent::SessionUpdated { session });
+        }
+    }
+}
+
 /// Mark a session whose tmux session has disappeared as [`SessionStatus::Dead`]
-/// and announce it, keeping everything else intact.
+/// and settle its worktree per the natural-exit rule (#82).
 ///
 /// The record, its [`PtyBridge`] and its sidecar all survive, so a client can
 /// still attach and read the replay buffer — the last thing a crashed agent
-/// printed. Artifacts are only released when the operator dismisses the session
-/// via [`SessionManager::kill`].
+/// printed. The worktree, though, is settled right away: a pristine tree is
+/// removed, anything else is retained into the store with reason
+/// `exited-with-unsaved-work` (#82) — nobody is waiting for an answer here,
+/// so there is nothing to refuse. Once settled, the session drops its
+/// worktree reference so a later dismissal neither re-probes nor retains
+/// twice. When settling is impossible (probe or store failure) nothing is
+/// destroyed: the tree stays attached to the dead record for a later forced
+/// dismissal (#81).
 ///
 /// Dead sessions do not survive a daemon restart: [`SessionManager::recover`]
 /// adopts only what tmux still holds.
 async fn mark_session_dead(inner: &Arc<Inner>, id: Uuid) {
-    let updated = {
+    let flipped = {
         let mut sessions = inner.sessions.lock().await;
         match sessions.get_mut(&id) {
             Some(record) if record.session.status == SessionStatus::Running => {
@@ -728,19 +961,114 @@ async fn mark_session_dead(inner: &Arc<Inner>, id: Uuid) {
                 // Release anyone attached; the scrollback survives for a later
                 // attach.
                 record.bridge.seal();
-                Some(record.session.clone())
+                let session = record.session.clone();
+                let worktree = record
+                    .worktree_base_repo
+                    .clone()
+                    .zip(record.worktree_path.clone());
+                let branch = record.worktree_branch.clone();
+                Some((session, worktree, branch))
             }
             _ => None,
         }
     };
-    let Some(session) = updated else {
+    let Some((mut session, worktree, branch)) = flipped else {
         return;
     };
     tracing::info!(%id, "session vanished from tmux — marking dead");
+
+    if let Some(wt) = &worktree {
+        if settle_worktree_on_exit(inner, id, wt, branch).await {
+            // The tree is settled (removed or retained); a stale "in the
+            // way" would describe something the session no longer holds.
+            session.blocked_work = None;
+            let mut sessions = inner.sessions.lock().await;
+            if let Some(record) = sessions.get_mut(&id) {
+                record.session.worktree = None;
+                record.session.blocked_work = None;
+                record.worktree_path = None;
+                record.worktree_base_repo = None;
+                record.worktree_branch = None;
+            }
+        }
+    }
+
     let _ = inner.sidecar.write(&session);
     let _ = inner.events.send(CatalogEvent::SessionUpdated { session });
 }
 
+/// Apply the exit rule (#82) to a vanished session's worktree: probe what
+/// would be lost through the kill's own predicate, then remove a pristine
+/// tree or retain anything else under `exited-with-unsaved-work` — recorded
+/// before anything is torn down, exactly as the forced kill does (#81). A
+/// removal that fails falls back to retaining, since whatever blocked it is
+/// by definition something worth keeping.
+///
+/// Returns whether the worktree was fully accounted for. When it wasn't,
+/// nothing was destroyed and the caller keeps the reference on the record.
+async fn settle_worktree_on_exit(
+    inner: &Arc<Inner>,
+    id: Uuid,
+    (base_repo, path): &(PathBuf, PathBuf),
+    known_branch: Option<String>,
+) -> bool {
+    let probe = match probe_worktree(&(base_repo.clone(), path.clone())).await {
+        Ok(probe) => probe,
+        Err(e) => {
+            tracing::error!(
+                %id,
+                path = %path.display(),
+                error = ?e,
+                "natural exit: could not probe the worktree; leaving it untouched"
+            );
+            return false;
+        }
+    };
+    if probe.is_clear() {
+        match inner.worktree_mgr.remove(base_repo, path) {
+            Ok(()) => {
+                tracing::info!(%id, path = %path.display(), "natural exit: pristine worktree removed");
+                return true;
+            }
+            Err(e) => {
+                tracing::warn!(
+                    %id,
+                    path = %path.display(),
+                    error = ?e,
+                    "natural exit: removal failed; falling back to retention"
+                );
+            }
+        }
+    }
+    match record_retention(
+        inner,
+        &(base_repo.clone(), path.clone()),
+        known_branch,
+        RetainedReason::ExitedWithUnsavedWork,
+    )
+    .await
+    {
+        Ok(entry) => {
+            tracing::info!(
+                %id,
+                path = %path.display(),
+                entry = %entry.id,
+                "natural exit: worktree retained with unsaved work"
+            );
+            true
+        }
+        Err(e) => {
+            tracing::error!(
+                %id,
+                path = %path.display(),
+                error = ?e,
+                "natural exit: could not record the retained worktree; leaving it untouched"
+            );
+            false
+        }
+    }
+}
+
 /// Tear down a session's artifacts after it has already been removed from the
 /// live map. Shared by [`SessionManager::kill`] and [`reap_dead_session`],
 /// which previously hand-rolled the same five-step choreography and only
@@ -750,7 +1078,17 @@ async fn mark_session_dead(inner: &Arc<Inner>, id: Uuid) {
 /// gone from the authoritative in-memory map, so a stray FIFO or sidecar can't
 /// resurrect it. `kill_tmux` is `true` for an explicit kill and `false` for the
 /// liveness reaper (tmux already lost the session).
-async fn cleanup_record(inner: &Arc<Inner>, id: Uuid, record: SessionRecord, kill_tmux: bool) {
+///
+/// `retain_worktree` is `true` for a forced kill (#81) that retained the
+/// worktree instead of removing it: the store entry is already written, so
+/// only the removal is skipped.
+async fn cleanup_record(
+    inner: &Arc<Inner>,
+    id: Uuid,
+    record: SessionRecord,
+    kill_tmux: bool,
+    retain_worktree: bool,
+) {
     if kill_tmux {
         let tmux = inner.tmux.clone();
         let _ = tmux_blocking(move || tmux.kill_session(id)).await;
@@ -759,11 +1097,18 @@ async fn cleanup_record(inner: &Arc<Inner>, id: Uuid, record: SessionRecord, kil
     if let Err(e) = inner.sidecar.delete(id) {
         tracing::warn!(error = ?e, %id, "cleanup: failed to delete sidecar");
     }
-    // The kill already passed the unsaved-work guard (#79), so this removal
-    // is unconditional; the manager's own nested-worktree refusal is all that
-    // can still leave a tree on disk, and it says where.
     if let (Some(base), Some(path)) = (&record.worktree_base_repo, &record.worktree_path) {
-        if let Err(e) = inner.worktree_mgr.remove(base, path) {
+        if retain_worktree {
+            tracing::info!(
+                %id,
+                path = %path.display(),
+                "forced kill: worktree retained in the store"
+            );
+        } else if let Err(e) = inner.worktree_mgr.remove(base, path) {
+            // The kill already passed the unsaved-work guard (#79), so this
+            // removal is unconditional; the manager's own nested-worktree
+            // refusal is all that can still leave a tree on disk, and it
+            // says where.
             tracing::warn!(
                 %id,
                 path = %path.display(),

crates/maestro-daemon/src/tmux.rs

@@ -264,6 +264,25 @@ impl Tmux {
         check(out)
     }
 
+    /// `tmux show-environment -t maestro-<id>`, parsed into KEY=VALUE pairs.
+    /// Test-facing view of what a spawned session actually inherits.
+    pub fn show_environment(&self, id: Uuid) -> Result<BTreeMap<String, String>, TmuxError> {
+        let name = session_name(id);
+        let out = self
+            .cmd()
+            .args(["show-environment", "-t", &name])
+            .output()?;
+        check(out.clone())?;
+        let stdout = String::from_utf8_lossy(&out.stdout);
+        let mut env = BTreeMap::new();
+        for line in stdout.lines() {
+            if let Some((k, v)) = line.split_once('=') {
+                env.insert(k.to_string(), v.to_string());
+            }
+        }
+        Ok(env)
+    }
+
     /// `tmux kill-server`. Best-effort cleanup used mostly by tests.
     pub fn kill_server(&self) -> Result<(), TmuxError> {
         let out = self.cmd().arg("kill-server").output()?;

crates/maestro-daemon/src/worktree.rs

@@ -174,6 +174,13 @@ impl WorktreeManager {
 /// The repository's main checkout. `--git-common-dir` points at the shared
 /// `.git` for every linked worktree, so its parent is the main tree. Falls
 /// back to the input when git can't answer.
+/// The repository a path belongs to: the main checkout, even when `path` is a
+/// linked worktree. Clients group sessions by this (#99), and placement uses it
+/// so a worktree is never nested inside another.
+pub fn main_checkout_of(path: &Path) -> PathBuf {
+    main_checkout(path)
+}
+
 fn main_checkout(path: &Path) -> PathBuf {
     let out = Command::new("git")
         .arg("-C")

crates/maestro-daemon/src/worktree_probe.rs

@@ -90,6 +90,14 @@ pub fn reclaim(base_repo: &Path, path: &Path) -> Result<(), ProbeError> {
     .map(|_| ())
 }
 
+/// Branch checked out at `path`. Sessions adopted from a sidecar carry no
+/// branch on record, so a forced kill (#81) asks the tree itself when it
+/// needs one for the retained store. `None` when git cannot answer.
+pub fn current_branch(path: &Path) -> Option<String> {
+    let out = run_git(path, ["rev-parse", "--abbrev-ref", "HEAD"]).ok()?;
+    Some(String::from_utf8_lossy(&out.stdout).trim().to_string())
+}
+
 fn run_git<I, S>(dir: &Path, args: I) -> Result<std::process::Output, ProbeError>
 where
     I: IntoIterator<Item = S>,

crates/maestro-daemon/tests/attach.rs

@@ -122,7 +122,7 @@ async fn pty_round_trip_through_real_tmux() {
         "marker not seen in {} bytes",
         got.len()
     );
-    let _ = h.manager.kill(id).await;
+    let _ = h.manager.kill(id, false).await;
 }
 
 #[tokio::test]
@@ -170,7 +170,7 @@ async fn multi_attach_broadcasts_to_every_client() {
         "client B missed marker"
     );
 
-    let _ = h.manager.kill(id).await;
+    let _ = h.manager.kill(id, false).await;
 }
 
 #[tokio::test]
@@ -219,7 +219,7 @@ async fn sends_close_frame_when_session_is_killed() {
     // give the broadcast subscriber a moment to register before killing.
     tokio::time::sleep(Duration::from_millis(100)).await;
 
-    h.manager.kill(id).await.unwrap();
+    h.manager.kill(id, false).await.unwrap();
 
     let mut saw_close = false;
     let deadline = std::time::Instant::now() + Duration::from_secs(2);
@@ -267,7 +267,7 @@ async fn ping_text_frame_gets_pong() {
         }
     }
     assert!(saw_pong, "no Pong frame received");
-    let _ = h.manager.kill(id).await;
+    let _ = h.manager.kill(id, false).await;
 }
 
 #[tokio::test]

crates/maestro-daemon/tests/blocked_work_cost.rs

@@ -0,0 +1,116 @@
+//! The performance contract of #83: the blocked-work pass must cost NO git
+//! probe at all for a session without a worktree, while a session with one is
+//! still probed.
+//!
+//! `git` itself is shimmed through PATH with a wrapper that logs every
+//! invocation before exec'ing the real binary, so the assertion counts actual
+//! probes rather than inferring them from state. This lives in its own test
+//! binary because it mutates the process environment.
+
+mod common;
+
+use std::collections::HashMap;
+use std::process::Command;
+use std::time::Duration;
+
+use common::{init_bare_repo, init_repo, push_all_to_origin, wait_for_async, DaemonFixture};
+use maestro_protocol::{CreateSessionRequest, InTheWay, WorktreeSpec};
+use tempfile::TempDir;
+
+fn request(cwd: &std::path::Path, repo: &std::path::Path, branch: &str) -> CreateSessionRequest {
+    CreateSessionRequest {
+        cwd: cwd.to_path_buf(),
+        command: "sleep 30".into(),
+        env: HashMap::new(),
+        metadata: HashMap::new(),
+        worktree: Some(WorktreeSpec {
+            base_repo: repo.to_path_buf(),
+            branch: branch.into(),
+            create_branch: true,
+        }),
+    }
+}
+
+#[tokio::test]
+async fn a_session_without_a_worktree_costs_no_probe() {
+    let fx = DaemonFixture::new();
+    let log = TempDir::new().unwrap();
+    let log_path = log.path().join("git-calls.log");
+
+    // Session A owns a real (pristine, pushed) worktree; session B has none.
+    let repo_a = TempDir::new().unwrap();
+    init_repo(repo_a.path());
+    init_bare_repo(&repo_a.path().join("origin.git"));
+    push_all_to_origin(repo_a.path(), &repo_a.path().join("origin.git"));
+    fx.manager
+        .create(request(repo_a.path(), repo_a.path(), "feat/probed"))
+        .await
+        .expect("create A");
+
+    let cwd_b = TempDir::new().unwrap();
+    let mut req_b = request(cwd_b.path(), cwd_b.path(), "feat/unused");
+    req_b.worktree = None;
+    fx.manager.create(req_b).await.expect("create B");
+
+    // Shim `git` AFTER setup so only watcher-driven probes get logged.
+    let real_git = String::from_utf8(
+        Command::new("sh")
+            .arg("-c")
+            .arg("command -v git")
+            .output()
+            .expect("locate git")
+            .stdout,
+    )
+    .unwrap()
+    .trim()
+    .to_string();
+    let shim_dir = TempDir::new().unwrap();
+    let script = format!(
+        "#!/bin/sh\nprintf '%s\\n' \"$*\" >> {}\nexec {} \"$@\"\n",
+        log_path.display(),
+        real_git,
+    );
+    std::fs::write(shim_dir.path().join("git"), script).unwrap();
+    #[cfg(unix)]
+    {
+        use std::os::unix::fs::PermissionsExt;
+        std::fs::set_permissions(
+            shim_dir.path().join("git"),
+            std::fs::Permissions::from_mode(0o755),
+        )
+        .unwrap();
+    }
+    let old_path = std::env::var("PATH").unwrap_or_default();
+    std::env::set_var(
+        "PATH",
+        format!("{}:{}", shim_dir.path().display(), old_path),
+    );
+
+    fx.manager.start_liveness_watcher_with_blocked_work(
+        Duration::from_millis(50),
+        Duration::from_millis(100),
+    );
+
+    // The pass demonstrably runs and probed A's tree...
+    wait_for_async(Duration::from_secs(5), || async {
+        fx.manager
+            .snapshot()
+            .await
+            .iter()
+            .any(|s| s.worktree.is_some() && s.blocked_work == Some(InTheWay::default()))
+    })
+    .await;
+
+    std::env::set_var("PATH", &old_path);
+
+    let calls = std::fs::read_to_string(&log_path).unwrap_or_default();
+    assert!(
+        !calls.is_empty(),
+        "the pass never probed anything — the shim saw no git call at all"
+    );
+    // ...while B — no worktree, so nothing to probe — was never touched.
+    assert!(
+        !calls.contains(cwd_b.path().to_str().unwrap()),
+        "a worktree-less session was probed:\n{calls}"
+    );
+}

crates/maestro-daemon/tests/common/mod.rs

@@ -176,6 +176,11 @@ impl DaemonFixture {
             manager =
                 manager.with_spawn_history(SpawnHistory::new(Self::history_path(&state_dir), days));
         }
+        // Same wiring as production: the manager records retained worktrees
+        // into the same dir the API reads back from (#78/#81).
+        let retained =
+            maestro_daemon::retained_store::RetainedStore::new(Self::retained_path(&state_dir));
+        manager = manager.with_retained_store(retained.clone());
         Self {
             tmux,
             manager,
@@ -187,6 +192,10 @@ impl DaemonFixture {
         state_dir.path().join("spawn-history.jsonl")
     }
 
+    fn retained_path(state_dir: &TempDir) -> PathBuf {
+        state_dir.path().join("retained-worktrees")
+    }
+
     pub fn spawn_history_path(&self) -> PathBuf {
         Self::history_path(&self.state_dir)
     }

crates/maestro-daemon/tests/local_api.rs

@@ -25,6 +25,13 @@ struct Harness {
     _fx: DaemonFixture,
 }
 
+impl Harness {
+    /// Store over the same dir the manager records into.
+    fn fx_retained(&self) -> maestro_daemon::retained_store::RetainedStore {
+        self._fx.retained_store()
+    }
+}
+
 async fn spawn(hostname: &str) -> Harness {
     spawn_with(
         hostname,
@@ -356,7 +363,6 @@ async fn delete_a_session_whose_worktree_holds_unsaved_work_returns_409_with_the
             worktree: Some(WorktreeSpec {
                 base_repo: repo.path().to_path_buf(),
                 branch: "feat/guarded".into(),
-                cleanup_on_kill: true,
                 create_branch: true,
             }),
         })
@@ -386,6 +392,61 @@ async fn delete_a_session_whose_worktree_holds_unsaved_work_returns_409_with_the
     assert!(h.manager.has(session.id).await, "the session keeps running");
 }
 
+/// `?force=true` on the wire (#81): the refusal is overridden, the session
+/// ends, and the answer is 200 with the retained worktree named — path,
+/// branch, reason — while the directory survives on disk.
+#[tokio::test]
+async fn delete_with_force_ends_the_session_and_answers_what_was_retained() {
+    let h = spawn("naps-laptop").await;
+    let repo = tempfile::TempDir::new().unwrap();
+    common::init_repo(repo.path());
+    let wt_path = repo
+        .path()
+        .join("worktrees")
+        .join("feat")
+        .join("guarded")
+        .to_path_buf();
+    let session = h
+        .manager
+        .create(CreateSessionRequest {
+            cwd: repo.path().to_path_buf(),
+            command: "sleep 60".into(),
+            env: HashMap::new(),
+            metadata: HashMap::new(),
+            worktree: Some(WorktreeSpec {
+                base_repo: repo.path().to_path_buf(),
+                branch: "feat/guarded".into(),
+                create_branch: true,
+            }),
+        })
+        .await
+        .unwrap();
+    std::fs::write(wt_path.join("README"), b"unsaved edits\n").unwrap();
+
+    let resp = reqwest::Client::new()
+        .delete(url(h.addr, &format!("/api/sessions/{}", session.id)))
+        .query(&[("force", "true")])
+        .send()
+        .await
+        .unwrap();
+    assert_eq!(resp.status(), reqwest::StatusCode::OK);
+    let body: maestro_protocol::KillOutcome = resp.json().await.unwrap();
+    let retained = body.retained.expect("force names what was kept");
+    assert_eq!(retained.path, wt_path);
+    assert_eq!(retained.branch, "feat/guarded");
+    assert_eq!(
+        retained.reason,
+        maestro_protocol::RetainedReason::ForceKilled
+    );
+
+    // The tree would have blocked; force must not have removed it.
+    assert!(wt_path.exists(), "a forced kill never removes the worktree");
+    // And the store entry exists, so reclaim can find it (#80).
+    let all = h.fx_retained().load_all().unwrap();
+    assert_eq!(all.len(), 1);
+    assert_eq!(all[0].id, retained.id);
+}
+
 #[tokio::test]
 async fn attach_ws_streams_pty_bytes() {
     let h = spawn("naps-laptop").await;
@@ -476,7 +537,7 @@ async fn events_ws_sends_a_snapshot_then_streams_deltas() {
         other => panic!("expected SessionAdded, got {other:?}"),
     }
 
-    h.manager.kill(created.id).await.expect("kill");
+    h.manager.kill(created.id, false).await.expect("kill");
 
     // Activity ticks may interleave; the removal is what we are waiting for.
     let deadline = tokio::time::Instant::now() + Duration::from_secs(5);

crates/maestro-daemon/tests/session_decisions.rs

@@ -30,6 +30,24 @@ impl Fx {
         Self::with_sidecar_dir(|tmp| tmp.join("sidecars"))
     }
 
+    /// Variant whose manager knows the daemon's own base URL (#103), the way
+    /// the production runner wires it from `[daemon].bind_addr`.
+    fn with_daemon_url(url: &str) -> Self {
+        let fx = Self::new();
+        fx.manager.set_daemon_url(url.to_string());
+        fx
+    }
+
+    /// The env map of the (single, expected) spawn call.
+    fn spawned_env(&self) -> BTreeMap<String, String> {
+        let calls = self.fake.calls();
+        let Some(Call::NewSessionPiped { env, .. }) = calls.first() else {
+            panic!("expected a spawn call, got {calls:?}");
+        };
+        assert_eq!(calls.len(), 1, "expected exactly one spawn: {calls:?}");
+        env.clone()
+    }
+
     fn with_sidecar_dir(pick: impl Fn(&std::path::Path) -> PathBuf) -> Self {
         let tmp = TempDir::new().expect("tempdir");
         let fake = Arc::new(FakePanes::new());
@@ -211,7 +229,7 @@ async fn killing_a_dead_session_dismisses_it_without_touching_tmux() {
     fx.manager.start_liveness_watcher(Duration::from_millis(25));
     wait_for_status(&fx.manager, s.id, SessionStatus::Dead).await;
 
-    fx.manager.kill(s.id).await.expect("dismiss");
+    fx.manager.kill(s.id, false).await.expect("dismiss");
 
     assert!(fx.manager.snapshot().await.is_empty());
     assert!(
@@ -261,16 +279,23 @@ async fn requested_env_reaches_tmux() {
 
     fx.manager.create(req).await.expect("create");
 
+    let spawned = match fx.fake.calls().first() {
+        Some(Call::NewSessionPiped { env, .. }) => env.clone(),
+        other => panic!("expected a spawn call, got {other:?}"),
+    };
+    let id = spawned
+        .get("MAESTRO_SESSION_ID")
+        .expect("spawn must export MAESTRO_SESSION_ID (#103)")
+        .clone();
+    // The daemon-owned variable rides alongside whatever was requested.
     let want: BTreeMap<String, String> = [
         ("EMPTY".to_string(), String::new()),
         ("FOO".to_string(), "bar".to_string()),
+        ("MAESTRO_SESSION_ID".to_string(), id),
     ]
     .into_iter()
     .collect();
-    match fx.fake.calls().first() {
-        Some(Call::NewSessionPiped { env, .. }) => assert_eq!(env, &want),
-        other => panic!("expected a spawn call, got {other:?}"),
-    }
+    assert_eq!(&spawned, &want);
 }
 
 #[tokio::test]
@@ -338,6 +363,9 @@ async fn activity_pass_emits_updated_only_when_something_changed() {
     // Still inside `activity::ACTIVE_WINDOW` (3s) since the spawn, so the
     // change here is `foreground`, not the activity state.
     assert_eq!(updated.activity, ActivityState::Active);
+    // A foreground/cwd-only change is not a state transition (#104): the
+    // sidebar's duration must keep counting from the original stamp.
+    assert_eq!(updated.activity_since, session.activity_since);
 
     // Drain anything already queued, then confirm a steady pane stays quiet.
     // Stays well inside the 3s window, so no Active -> Idle transition either.
@@ -349,6 +377,70 @@ async fn activity_pass_emits_updated_only_when_something_changed() {
     );
 }
 
+/// The sidebar's duration (#104) is time in the *current* state, so
+/// `activity_since` is stamped exactly when the decided state differs from
+/// the stored one — once per transition. Stamping it every tick would make
+/// the duration permanently read zero.
+#[tokio::test]
+async fn activity_transition_stamps_activity_since_once_per_transition() {
+    let fx = Fx::new();
+    let session = fx
+        .manager
+        .create(fx.request("sleep 300"))
+        .await
+        .expect("create");
+    fx.fake.set_pane_info(
+        session.id,
+        PaneInfo {
+            // Nothing reads from this pid: `awaiting_input` is deterministically
+            // false, so past `ACTIVE_WINDOW` the session decides as Idle.
+            pane_pid: i32::MAX,
+            command: "sleep".into(),
+            tty: "/dev/null".into(),
+            current_path: String::new(),
+        },
+    );
+    let mut events = fx.manager.events();
+    fx.manager.start_liveness_watcher(Duration::from_millis(25));
+
+    let idle = wait_for_activity(&fx.manager, session.id, ActivityState::Idle).await;
+    assert!(
+        idle.activity_since >= session.activity_since + chrono::Duration::seconds(2),
+        "the Active -> Idle transition must stamp a fresh activity_since \
+         (spawn stamp {:?}, transition stamp {:?})",
+        session.activity_since,
+        idle.activity_since
+    );
+
+    // Steady Idle across many more ticks must not re-stamp — no further
+    // SessionUpdated at all, or the sidebar clock would keep resetting.
+    while events.try_recv().is_ok() {}
+    tokio::time::sleep(Duration::from_millis(300)).await;
+    assert!(
+        matches!(events.try_recv(), Err(TryRecvError::Empty)),
+        "a steady state must not re-emit (and re-stamp) on every tick"
+    );
+}
+
+async fn wait_for_activity(
+    manager: &SessionManager,
+    id: uuid::Uuid,
+    want: ActivityState,
+) -> maestro_protocol::Session {
+    let deadline = tokio::time::Instant::now() + Duration::from_secs(6);
+    loop {
+        if tokio::time::Instant::now() >= deadline {
+            panic!("timed out waiting for {id} to become {want:?}");
+        }
+        if let Some(s) = manager.snapshot().await.into_iter().find(|s| s.id == id) {
+            if s.activity == want {
+                return s;
+            }
+        }
+        tokio::time::sleep(Duration::from_millis(20)).await;
+    }
+}
+
 async fn wait_for_updated(
     events: &mut tokio::sync::broadcast::Receiver<CatalogEvent>,
 ) -> maestro_protocol::Session {
@@ -371,7 +463,7 @@ async fn killing_an_unknown_session_is_reported_as_not_found() {
     let fx = Fx::new();
     let err = fx
         .manager
-        .kill(uuid::Uuid::new_v4())
+        .kill(uuid::Uuid::new_v4(), false)
         .await
         .expect_err("should fail");
     assert_eq!(err.to_error_info().code, "not_found");
@@ -396,3 +488,70 @@ fn attaching_spawn_history_after_cloning_panics() {
         7,
     ));
 }
+
+/// Every tmux-spawned session learns who it is (#103): its own UUID under
+/// `MAESTRO_SESSION_ID`, so the reporting hook in #106 can name the session
+/// it is running inside.
+#[tokio::test]
+async fn spawn_exports_maestro_session_id() {
+    let fx = Fx::new();
+    let s = fx.manager.create(fx.request("bash")).await.expect("create");
+
+    let env = fx.spawned_env();
+    assert_eq!(
+        env.get("MAESTRO_SESSION_ID").map(String::as_str),
+        Some(&s.id.to_string()[..]),
+        "MAESTRO_SESSION_ID must be the session's UUID, got {env:?}"
+    );
+}
+
+/// The hook also needs to know where to report to: `MAESTRO_URL` carries the
+/// daemon's base URL derived from `[daemon].bind_addr` (#103).
+#[tokio::test]
+async fn spawn_exports_maestro_url_when_the_daemon_is_wired() {
+    let fx = Fx::with_daemon_url("http://127.0.0.1:7070");
+    fx.manager.create(fx.request("bash")).await.expect("create");
+
+    let env = fx.spawned_env();
+    assert_eq!(
+        env.get("MAESTRO_URL").map(String::as_str),
+        Some("http://127.0.0.1:7070"),
+        "MAESTRO_URL must be the daemon's base URL, got {env:?}"
+    );
+}
+
+/// Without a wired URL (tests, or a caller that never set one) only the
+/// session id is injected — an empty or bogus `MAESTRO_URL` would send the
+/// #106 hook's reports nowhere useful.
+#[tokio::test]
+async fn spawn_omits_maestro_url_when_not_wired() {
+    let fx = Fx::new();
+    fx.manager.create(fx.request("bash")).await.expect("create");
+
+    let env = fx.spawned_env();
+    assert!(
+        !env.contains_key("MAESTRO_URL"),
+        "MAESTRO_URL must be absent when no daemon URL is known, got {env:?}"
+    );
+}
+
+/// The daemon-owned variables win over anything the spawner sent: a client
+/// cannot spoof another session's identity.
+#[tokio::test]
+async fn spawn_overrides_client_supplied_maestro_variables() {
+    let fx = Fx::with_daemon_url("http://127.0.0.1:7070");
+    let mut req = fx.request("bash");
+    req.env.insert(
+        "MAESTRO_SESSION_ID".into(),
+        "00000000-0000-0000-0000-000000000000".into(),
+    );
+    req.env.insert("MAESTRO_URL".into(), "http://evil:1".into());
+    let s = fx.manager.create(req).await.expect("create");
+
+    let env = fx.spawned_env();
+    assert_eq!(env.get("MAESTRO_SESSION_ID"), Some(&s.id.to_string()));
+    assert_eq!(
+        env.get("MAESTRO_URL"),
+        Some(&"http://127.0.0.1:7070".to_string())
+    );
+}

crates/maestro-daemon/tests/session_manager.rs

@@ -8,7 +8,9 @@ use std::process::Command;
 use std::sync::Arc;
 use std::time::Duration;
 
-use common::{init_bare_repo, init_repo, push_all_to_origin, wait_for_async, DaemonFixture};
+use common::{
+    init_bare_repo, init_repo, push_all_to_origin, wait_for_async, DaemonFixture, TmuxFixture,
+};
 use maestro_daemon::SessionError;
 use maestro_protocol::CreateSessionRequest;
 use maestro_protocol::{CatalogEvent, SessionStatus, WorktreeSpec};
@@ -44,7 +46,7 @@ async fn create_then_kill_round_trip() {
     // FIFO should also exist
     assert!(fx.fifo_dir().join(format!("{}.fifo", session.id)).exists());
 
-    fx.manager.kill(session.id).await.expect("kill");
+    fx.manager.kill(session.id, false).await.expect("kill");
     assert!(!fx.manager.has(session.id).await);
     assert!(!fx
         .sidecar_dir()
@@ -79,7 +81,7 @@ async fn create_appends_to_spawn_history() {
     assert_eq!(recents[0].cwd, cwd.path());
     assert_eq!(recents[0].last_command, "sleep 30");
 
-    fx.manager.kill(session.id).await.expect("kill");
+    fx.manager.kill(session.id, false).await.expect("kill");
     // History is durable — it survives the kill that deletes the sidecar.
     assert_eq!(fx.manager.recent_dirs().len(), 1);
 }
@@ -185,7 +187,7 @@ async fn create_captures_initial_output_in_replay_buffer() {
         "first-line marker never reached the replay buffer — pipe-pane raced past the child's initial output",
     );
 
-    fx.manager.kill(s.id).await.unwrap();
+    fx.manager.kill(s.id, false).await.unwrap();
 }
 
 /// Regression for NAP-228: after `recover`, PTY output must reach new
@@ -251,7 +253,7 @@ async fn recover_re_pipes_pane_so_output_reaches_subscribers() {
         String::from_utf8_lossy(&buf),
     );
 
-    revived.kill(s.id).await.unwrap();
+    revived.kill(s.id, false).await.unwrap();
 }
 
 #[tokio::test]
@@ -300,7 +302,7 @@ async fn pty_broadcast_delivers_bytes_to_subscribers() {
     assert!(buf_a.windows(want.len()).any(|w| w == want), "A missed");
     assert!(buf_b.windows(want.len()).any(|w| w == want), "B missed");
 
-    fx.manager.kill(s.id).await.unwrap();
+    fx.manager.kill(s.id, false).await.unwrap();
     let _ = (cwd, PathBuf::from("/"));
 }
 
@@ -359,12 +361,73 @@ async fn liveness_watcher_marks_dead_sessions_and_keeps_them_until_dismissed() {
     );
 
     // Dismissing it is what finally releases the artifacts.
-    fx.manager.kill(s.id).await.expect("dismiss");
+    fx.manager.kill(s.id, false).await.expect("dismiss");
     assert!(!fx.manager.has(s.id).await);
     assert!(!fx.sidecar_dir().join(format!("{}.json", s.id)).exists());
     assert!(!fx.fifo_dir().join(format!("{}.fifo", s.id)).exists());
 }
 
+/// #83: the watcher refreshes `Session.blocked_work` on its own cadence —
+/// first "nothing blocks" for a pristine tree, then the breakdown once the
+/// tree picks up unsaved work, so clients can warn before the kill attempt.
+#[tokio::test]
+async fn watcher_refreshes_the_blocked_work_indicator() {
+    let fx = DaemonFixture::new();
+    let repo = TempDir::new().unwrap();
+    init_repo(repo.path());
+    let wt_path = repo.path().join("worktrees").join("feat").join("indicator");
+
+    fx.manager
+        .create(CreateSessionRequest {
+            cwd: repo.path().to_path_buf(),
+            command: "sleep 30".into(),
+            env: HashMap::new(),
+            metadata: HashMap::new(),
+            worktree: Some(WorktreeSpec {
+                base_repo: repo.path().to_path_buf(),
+                branch: "feat/indicator".into(),
+                create_branch: true,
+            }),
+        })
+        .await
+        .expect("create");
+
+    // Pushed and clean: nothing in the way, and the indicator must say so.
+    let origin = TempDir::new().unwrap();
+    init_bare_repo(origin.path());
+    push_all_to_origin(repo.path(), origin.path());
+
+    fx.manager.start_liveness_watcher_with_blocked_work(
+        Duration::from_millis(50),
+        Duration::from_millis(100),
+    );
+
+    wait_for_async(Duration::from_secs(5), || async {
+        fx.manager.snapshot().await[0].blocked_work == Some(maestro_protocol::InTheWay::default())
+    })
+    .await;
+
+    // Unsaved work appears; the next pass must surface it.
+    std::fs::write(wt_path.join("README"), b"unsaved edits\n").unwrap();
+    std::fs::write(wt_path.join("notes.txt"), b"untracked\n").unwrap();
+    wait_for_async(Duration::from_secs(5), || async {
+        matches!(
+            &fx.manager.snapshot().await[0].blocked_work,
+            Some(b) if b.uncommitted_files >= 1 && b.untracked_files >= 1
+        )
+    })
+    .await;
+
+    // A steady state must not re-emit every tick (#83 change-detection).
+    let mut events = fx.manager.events();
+    while events.try_recv().is_ok() {}
+    tokio::time::sleep(Duration::from_millis(400)).await;
+    assert!(
+        !matches!(events.try_recv(), Ok(CatalogEvent::SessionUpdated { .. })),
+        "an unchanged worktree must not re-emit SessionUpdated"
+    );
+}
+
 /// Cleanup on kill is unconditional once the guard passes (#79): even a spec
 /// that says "don't clean up" loses its worktree — the branch was pushed, so
 /// nothing in the tree is unique and removal goes ahead.
@@ -385,7 +448,6 @@ async fn kill_removes_worktree_even_when_spec_says_keep() {
             worktree: Some(WorktreeSpec {
                 base_repo: repo.path().to_path_buf(),
                 branch: "feat/keep".into(),
-                cleanup_on_kill: false,
                 create_branch: true,
             }),
         })
@@ -398,7 +460,7 @@ async fn kill_removes_worktree_even_when_spec_says_keep() {
     init_bare_repo(origin.path());
     push_all_to_origin(repo.path(), origin.path());
 
-    fx.manager.kill(s.id).await.expect("kill");
+    fx.manager.kill(s.id, false).await.expect("kill");
     assert!(!wt_path.exists(), "worktree must be removed on kill");
 }
 
@@ -423,7 +485,6 @@ async fn killing_refuses_a_worktree_with_unsaved_work_and_keeps_the_session() {
             worktree: Some(WorktreeSpec {
                 base_repo: repo.path().to_path_buf(),
                 branch: "feat/guarded".into(),
-                cleanup_on_kill: true,
                 create_branch: true,
             }),
         })
@@ -432,7 +493,11 @@ async fn killing_refuses_a_worktree_with_unsaved_work_and_keeps_the_session() {
     std::fs::write(wt_path.join("README"), b"unsaved edits\n").unwrap();
     std::fs::write(wt_path.join("notes.txt"), b"untracked\n").unwrap();
 
-    let err = fx.manager.kill(s.id).await.expect_err("kill must refuse");
+    let err = fx
+        .manager
+        .kill(s.id, false)
+        .await
+        .expect_err("kill must refuse");
     let SessionError::KillGuarded(breakdown) = err else {
         panic!("expected KillGuarded, got {err:?}");
     };
@@ -456,7 +521,10 @@ async fn killing_refuses_a_worktree_with_unsaved_work_and_keeps_the_session() {
     let origin = TempDir::new().unwrap();
     init_bare_repo(origin.path());
     push_all_to_origin(repo.path(), origin.path());
-    fx.manager.kill(s.id).await.expect("kill after saving");
+    fx.manager
+        .kill(s.id, false)
+        .await
+        .expect("kill after saving");
     assert!(!fx.manager.has(s.id).await);
 }
 
@@ -480,14 +548,17 @@ async fn killing_refuses_until_the_branch_is_pushed() {
             worktree: Some(WorktreeSpec {
                 base_repo: repo.path().to_path_buf(),
                 branch: "feat/pushed".into(),
-                cleanup_on_kill: true,
                 create_branch: true,
             }),
         })
         .await
         .expect("create");
 
-    let err = fx.manager.kill(s.id).await.expect_err("unpushed blocks");
+    let err = fx
+        .manager
+        .kill(s.id, false)
+        .await
+        .expect_err("unpushed blocks");
     let SessionError::KillGuarded(breakdown) = err else {
         panic!("expected KillGuarded, got {err:?}");
     };
@@ -499,11 +570,116 @@ async fn killing_refuses_until_the_branch_is_pushed() {
     init_bare_repo(origin.path());
     push_all_to_origin(repo.path(), origin.path());
 
-    fx.manager.kill(s.id).await.expect("pushed branch kills");
+    fx.manager
+        .kill(s.id, false)
+        .await
+        .expect("pushed branch kills");
     assert!(!wt_path.exists());
     assert!(!fx.manager.has(s.id).await);
 }
 
+/// `--force` overrides the refusal and nothing else (#81): the session ends,
+/// but the guarded worktree is RETAINED — never removed — and enters the
+/// retained store with reason `force-killed`. The outcome names what was
+/// kept, so a client can say where the work went.
+#[tokio::test]
+async fn force_killing_a_guarded_worktree_retains_it_in_the_store() {
+    let fx = DaemonFixture::new();
+    let repo = TempDir::new().unwrap();
+    init_repo(repo.path());
+    let wt_path = repo.path().join("worktrees").join("feat").join("forced");
+
+    let s = fx
+        .manager
+        .create(CreateSessionRequest {
+            cwd: repo.path().to_path_buf(),
+            command: "sleep 30".into(),
+            env: HashMap::new(),
+            metadata: HashMap::new(),
+            worktree: Some(WorktreeSpec {
+                base_repo: repo.path().to_path_buf(),
+                branch: "feat/forced".into(),
+                create_branch: true,
+            }),
+        })
+        .await
+        .expect("create");
+    std::fs::write(wt_path.join("README"), b"unsaved edits\n").unwrap();
+
+    // Without force the same kill is refused (#79).
+    assert!(fx.manager.kill(s.id, false).await.is_err());
+
+    let outcome = fx
+        .manager
+        .kill(s.id, true)
+        .await
+        .expect("force overrides the refusal");
+
+    // The tree would have blocked, so force must NOT have removed it...
+    assert!(
+        wt_path.exists(),
+        "a forced kill never removes a tree that would have blocked"
+    );
+    // ...but the session itself still ends.
+    assert!(!fx.manager.has(s.id).await);
+    assert!(!fx.sidecar_dir().join(format!("{}.json", s.id)).exists());
+
+    let retained = outcome.retained.expect("the outcome names what was kept");
+    assert_eq!(retained.path, wt_path);
+    assert_eq!(retained.branch, "feat/forced");
+    assert_eq!(
+        retained.reason,
+        maestro_protocol::RetainedReason::ForceKilled
+    );
+    assert!(
+        retained.in_the_way.uncommitted_files >= 1,
+        "the outcome carries what blocked the unforced kill"
+    );
+
+    // The store holds the same entry, so reclaim can find it later (#80).
+    let all = fx.retained_store().load_all().expect("load_all");
+    assert_eq!(all.len(), 1);
+    assert_eq!(all[0].id, retained.id);
+    assert_eq!(all[0].path, wt_path);
+    assert_eq!(all[0].branch, "feat/forced");
+}
+
+/// Force overrides the *refusal*, not ordinary cleanup (#81): a tree whose
+/// guard is clear never needed the override, so a forced kill removes it as
+/// usual and retains nothing.
+#[tokio::test]
+async fn force_on_a_clear_worktree_removes_it_as_usual() {
+    let fx = DaemonFixture::new();
+    let repo = TempDir::new().unwrap();
+    init_repo(repo.path());
+    let wt_path = repo.path().join("worktrees").join("feat").join("clear");
+
+    let s = fx
+        .manager
+        .create(CreateSessionRequest {
+            cwd: repo.path().to_path_buf(),
+            command: "sleep 30".into(),
+            env: HashMap::new(),
+            metadata: HashMap::new(),
+            worktree: Some(WorktreeSpec {
+                base_repo: repo.path().to_path_buf(),
+                branch: "feat/clear".into(),
+                create_branch: true,
+            }),
+        })
+        .await
+        .expect("create");
+
+    let origin = TempDir::new().unwrap();
+    init_bare_repo(origin.path());
+    push_all_to_origin(repo.path(), origin.path());
+
+    let outcome = fx.manager.kill(s.id, true).await.expect("kill");
+    assert!(!wt_path.exists(), "a clear tree needs no override");
+    assert_eq!(outcome.retained, None);
+    assert!(fx.retained_store().load_all().unwrap().is_empty());
+}
+
 /// Ignored files NEVER block (#79): build output like `target/` exists in
 /// every Rust checkout, and an ignored-only worktree stays killable.
 #[tokio::test]
@@ -530,7 +706,6 @@ async fn killing_an_ignored_only_worktree_succeeds() {
             worktree: Some(WorktreeSpec {
                 base_repo: repo.path().to_path_buf(),
                 branch: "feat/rusty".into(),
-                cleanup_on_kill: true,
                 create_branch: true,
             }),
         })
@@ -543,13 +718,196 @@ async fn killing_an_ignored_only_worktree_succeeds() {
     push_all_to_origin(repo.path(), origin.path());
 
     fx.manager
-        .kill(s.id)
+        .kill(s.id, false)
         .await
         .expect("ignored files never block");
     assert!(!wt_path.exists());
     assert!(!fx.manager.has(s.id).await);
 }
 
+/// Natural exit (#82): a session that ends on its own never reaches the kill
+/// path, so the watcher applies the kill's rule itself. A worktree holding
+/// unsaved work is RETAINED into the store with reason
+/// `exited-with-unsaved-work`; the session stays in the catalog marked dead
+/// until dismissed — and dismissing it afterwards neither refuses nor
+/// retains a second time.
+#[tokio::test]
+async fn natural_exit_of_a_guarded_worktree_retains_it_in_the_store() {
+    let fx = DaemonFixture::new();
+    let repo = TempDir::new().unwrap();
+    init_repo(repo.path());
+    let wt_path = repo.path().join("worktrees").join("feat").join("exited");
+
+    let s = fx
+        .manager
+        .create(CreateSessionRequest {
+            cwd: repo.path().to_path_buf(),
+            command: "sleep 30".into(),
+            env: HashMap::new(),
+            metadata: HashMap::new(),
+            worktree: Some(WorktreeSpec {
+                base_repo: repo.path().to_path_buf(),
+                branch: "feat/exited".into(),
+                create_branch: true,
+            }),
+        })
+        .await
+        .expect("create");
+    std::fs::write(wt_path.join("README"), b"unsaved edits\n").unwrap();
+
+    // The command finishes / the operator types exit: tmux loses the session.
+    fx.tmux.tmux.kill_session(s.id).expect("kill tmux directly");
+    fx.manager.start_liveness_watcher(Duration::from_millis(50));
+    wait_for_async(Duration::from_secs(3), || async {
+        fx.manager.status(s.id).await == Some(SessionStatus::Dead)
+    })
+    .await;
+
+    // The tree would have blocked a kill, so the exit kept it...
+    assert!(
+        wt_path.exists(),
+        "a dirty worktree must be retained on natural exit"
+    );
+    // ...in the store, under the exit reason.
+    let all = fx.retained_store().load_all().expect("load_all");
+    assert_eq!(all.len(), 1);
+    assert_eq!(all[0].path, wt_path);
+    assert_eq!(all[0].branch, "feat/exited");
+    assert_eq!(
+        all[0].reason,
+        maestro_protocol::RetainedReason::ExitedWithUnsavedWork
+    );
+
+    // The session itself stays until dismissed; its worktree reference is
+    // settled, so dismissal is neither refused nor retained twice.
+    // (`Dead` is observable a moment before the settle step finishes.)
+    wait_for_async(Duration::from_secs(3), || async {
+        let s = &fx.manager.snapshot().await[0];
+        s.worktree.is_none() && s.blocked_work.is_none()
+    })
+    .await;
+    let snap = fx.manager.snapshot().await;
+    assert_eq!(snap.len(), 1);
+    assert_eq!(snap[0].worktree, None);
+
+    fx.manager.kill(s.id, false).await.expect("dismiss");
+    assert!(!fx.manager.has(s.id).await);
+    assert!(
+        wt_path.exists(),
+        "dismissal must not remove what was retained"
+    );
+    assert_eq!(
+        fx.retained_store().load_all().unwrap().len(),
+        1,
+        "dismissal must not record a second entry for the same tree"
+    );
+}
+
+/// Natural exit (#82), pristine side of the same rule: nothing in the tree,
+/// nothing to keep — the worktree is removed and no store entry appears.
+#[tokio::test]
+async fn natural_exit_of_a_pristine_worktree_removes_it() {
+    let fx = DaemonFixture::new();
+    let repo = TempDir::new().unwrap();
+    init_repo(repo.path());
+    let wt_path = repo.path().join("worktrees").join("feat").join("clean");
+
+    let s = fx
+        .manager
+        .create(CreateSessionRequest {
+            cwd: repo.path().to_path_buf(),
+            command: "sleep 30".into(),
+            env: HashMap::new(),
+            metadata: HashMap::new(),
+            worktree: Some(WorktreeSpec {
+                base_repo: repo.path().to_path_buf(),
+                branch: "feat/clean".into(),
+                create_branch: true,
+            }),
+        })
+        .await
+        .expect("create");
+
+    // Push everything so the branch has no unpushed commits: fully pristine.
+    let origin = TempDir::new().unwrap();
+    init_bare_repo(origin.path());
+    push_all_to_origin(repo.path(), origin.path());
+
+    fx.tmux.tmux.kill_session(s.id).expect("kill tmux directly");
+    fx.manager.start_liveness_watcher(Duration::from_millis(50));
+    wait_for_async(Duration::from_secs(3), || async {
+        fx.manager.status(s.id).await == Some(SessionStatus::Dead)
+    })
+    .await;
+
+    assert!(
+        !wt_path.exists(),
+        "a pristine worktree leaves nothing behind"
+    );
+    assert!(
+        fx.retained_store().load_all().unwrap().is_empty(),
+        "nothing was retained"
+    );
+    assert!(
+        fx.manager.has(s.id).await,
+        "the session stays until dismissed"
+    );
+}
+
+/// When nothing can be recorded — here: no retained store wired — the exit
+/// destroys nothing. The tree stays on disk AND stays attached to the dead
+/// record, where dismissing it later still goes through #81's forced-kill
+/// retention. Losing the store must not lose the work.
+#[tokio::test]
+async fn natural_exit_without_a_retained_store_destroys_nothing() {
+    let tmux = TmuxFixture::new();
+    let state_dir = TempDir::new().unwrap();
+    let manager = maestro_daemon::SessionManager::new(
+        Arc::new(tmux.tmux.clone()),
+        maestro_daemon::sidecar::SidecarStore::new(state_dir.path().join("sessions")),
+        maestro_daemon::worktree::WorktreeManager::new(None),
+        state_dir.path().join("fifos"),
+    );
+    // Deliberately NO with_retained_store.
+
+    let repo = TempDir::new().unwrap();
+    init_repo(repo.path());
+    let wt_path = repo.path().join("worktrees").join("feat").join("nostore");
+
+    let s = manager
+        .create(CreateSessionRequest {
+            cwd: repo.path().to_path_buf(),
+            command: "sleep 30".into(),
+            env: HashMap::new(),
+            metadata: HashMap::new(),
+            worktree: Some(WorktreeSpec {
+                base_repo: repo.path().to_path_buf(),
+                branch: "feat/nostore".into(),
+                create_branch: true,
+            }),
+        })
+        .await
+        .expect("create");
+    std::fs::write(wt_path.join("README"), b"unsaved edits\n").unwrap();
+
+    tmux.tmux.kill_session(s.id).expect("kill tmux directly");
+    manager.start_liveness_watcher(Duration::from_millis(50));
+    wait_for_async(Duration::from_secs(3), || async {
+        manager.status(s.id).await == Some(SessionStatus::Dead)
+    })
+    .await;
+
+    assert!(
+        wt_path.exists(),
+        "nothing may be destroyed when it cannot be recorded"
+    );
+    let snap = manager.snapshot().await;
+    assert!(
+        snap[0].worktree.is_some(),
+        "the tree must stay attached to the record so a later forced kill can retain it"
+    );
+}
+
 fn run_git_in(dir: &std::path::Path, args: &[&str]) {
     let out = Command::new("git")
         .arg("-C")
@@ -587,5 +945,103 @@ async fn liveness_watcher_leaves_running_sessions_alone() {
     tokio::time::sleep(Duration::from_millis(400)).await;
     assert!(fx.manager.has(s.id).await, "live session got reaped");
 
-    fx.manager.kill(s.id).await.unwrap();
+    fx.manager.kill(s.id, false).await.unwrap();
+}
+
+/// #99: clients group a session under `worktree.base_repo`, so that field has
+/// to name the repository even when the spawn request pointed at a linked
+/// worktree. Recording the request verbatim put the session in a folder of its
+/// own — `<repo>/worktrees/<branch>` — instead of under the repo.
+#[tokio::test]
+async fn worktree_base_repo_records_the_main_checkout_not_the_request() {
+    let fx = DaemonFixture::new();
+    let repo = TempDir::new().unwrap();
+    init_repo(repo.path());
+
+    // A linked worktree of that repo, then a spawn whose `base_repo` names it
+    // rather than the main checkout — what happens when the operator spawns
+    // from inside a worktree.
+    let first = fx
+        .manager
+        .create(CreateSessionRequest {
+            cwd: repo.path().to_path_buf(),
+            command: "sleep 30".into(),
+            env: HashMap::new(),
+            metadata: HashMap::new(),
+            worktree: Some(WorktreeSpec {
+                base_repo: repo.path().to_path_buf(),
+                branch: "feat/one".into(),
+                create_branch: true,
+            }),
+        })
+        .await
+        .expect("create first");
+    let inner_worktree = first.worktree.expect("first has a worktree").path;
+
+    let second = fx
+        .manager
+        .create(CreateSessionRequest {
+            cwd: inner_worktree.clone(),
+            command: "sleep 30".into(),
+            env: HashMap::new(),
+            metadata: HashMap::new(),
+            worktree: Some(WorktreeSpec {
+                base_repo: inner_worktree.clone(),
+                branch: "feat/two".into(),
+                create_branch: true,
+            }),
+        })
+        .await
+        .expect("create second");
+
+    let wt = second.worktree.expect("second has a worktree");
+    assert_eq!(
+        wt.base_repo,
+        repo.path()
+            .canonicalize()
+            .unwrap_or_else(|_| repo.path().to_path_buf()),
+        "base_repo must be the repository, not the worktree the request named",
+    );
+    assert_ne!(wt.base_repo, inner_worktree, "the worktree is not the repo");
+}
+
+/// #103: every tmux-spawned session carries the daemon's identity variables in
+/// its environment — its UUID under `MAESTRO_SESSION_ID` and the daemon's base
+/// URL under `MAESTRO_URL` — so the in-session reporting hook (#106) can find
+/// both without any out-of-band channel.
+#[tokio::test]
+async fn spawned_sessions_export_maestro_session_id_and_url() {
+    let fx = DaemonFixture::new();
+    fx.manager
+        .set_daemon_url("http://127.0.0.1:7071".to_string());
+    let cwd = TempDir::new().unwrap();
+
+    let s = fx
+        .manager
+        .create(CreateSessionRequest {
+            cwd: cwd.path().to_path_buf(),
+            command: "sleep 30".into(),
+            env: HashMap::new(),
+            metadata: HashMap::new(),
+            worktree: None,
+        })
+        .await
+        .expect("create");
+
+    let env = fx
+        .tmux
+        .tmux
+        .show_environment(s.id)
+        .expect("show-environment");
+    assert_eq!(
+        env.get("MAESTRO_SESSION_ID"),
+        Some(&s.id.to_string()),
+        "session env: {env:?}"
+    );
+    assert_eq!(
+        env.get("MAESTRO_URL"),
+        Some(&"http://127.0.0.1:7071".to_string())
+    );
+
+    fx.manager.kill(s.id, false).await.expect("kill");
 }

crates/maestro-daemon/tests/sidecar.rs

@@ -27,7 +27,9 @@ fn sample(id: Uuid) -> Session {
         foreground: None,
         activity: Default::default(),
         last_activity_at: chrono::Utc::now(),
+        activity_since: chrono::Utc::now(),
         current_cwd: Some(PathBuf::from("/tmp/work/crates")),
+        blocked_work: None,
     }
 }
 

crates/maestro-e2e/src/client.rs

@@ -12,7 +12,8 @@ use std::time::Duration;
 
 use futures_util::{SinkExt, StreamExt};
 use maestro_protocol::{
-    BranchInfo, CatalogEvent, CreateSessionRequest, DaemonClient, Project, Session,
+    BranchInfo, CatalogEvent, CreateSessionRequest, DaemonClient, KillOutcome, Project,
+    RetainedWorktree, Session,
 };
 use tokio_tungstenite::tungstenite::client::IntoClientRequest;
 use tokio_tungstenite::tungstenite::Message as WsMessage;
@@ -61,7 +62,21 @@ impl TestClient {
     }
 
     pub async fn kill_session(&self, id: Uuid) -> Result<(), ClientError> {
-        Ok(self.daemon.kill_session(id).await?)
+        Ok(self.daemon.kill_session(id, false).await.map(|_| ())?)
+    }
+
+    /// Kill with `force=true`: overrides a kill refusal and retains the
+    /// guarded worktree (#81). Answers with what was kept.
+    pub async fn kill_session_forced(&self, id: Uuid) -> Result<KillOutcome, ClientError> {
+        Ok(self.daemon.kill_session(id, true).await?)
+    }
+
+    pub async fn list_worktrees(&self) -> Result<Vec<RetainedWorktree>, ClientError> {
+        Ok(self.daemon.list_worktrees().await?)
+    }
+
+    pub async fn reclaim_worktree(&self, id: Uuid) -> Result<(), ClientError> {
+        Ok(self.daemon.reclaim_worktree(id).await?)
     }
 
     pub async fn list_projects(&self) -> Result<Vec<Project>, ClientError> {

crates/maestro-e2e/tests/e2e.rs

@@ -35,6 +35,17 @@ fn create_req(cwd: &std::path::Path, command: &str) -> CreateSessionRequest {
     }
 }
 
+/// A worktree spec built through its wire shape. The daemon and clients ship
+/// together (#87 dropped `cleanup_on_kill` from the struct), so the JSON
+/// object carries only the fields the lifecycle actually honours.
+fn worktree_spec(base_repo: &std::path::Path, branch: &str, create_branch: bool) -> WorktreeSpec {
+    WorktreeSpec {
+        base_repo: base_repo.to_path_buf(),
+        branch: branch.into(),
+        create_branch,
+    }
+}
+
 /// Spawn request carrying a worktree spec against `base`.
 fn worktree_req(base: &std::path::Path, branch: &str, create_branch: bool) -> CreateSessionRequest {
     CreateSessionRequest {
@@ -42,12 +53,7 @@ fn worktree_req(base: &std::path::Path, branch: &str, create_branch: bool) -> Cr
         command: "sleep 30".into(),
         env: HashMap::new(),
         metadata: HashMap::new(),
-        worktree: Some(WorktreeSpec {
-            base_repo: base.to_path_buf(),
-            branch: branch.into(),
-            cleanup_on_kill: true,
-            create_branch,
-        }),
+        worktree: Some(worktree_spec(base, branch, create_branch)),
     }
 }
 
@@ -141,12 +147,7 @@ async fn kill_removes_clean_worktree() {
         command: "sleep 30".into(),
         env: HashMap::new(),
         metadata: HashMap::new(),
-        worktree: Some(WorktreeSpec {
-            base_repo: base.path().to_path_buf(),
-            branch: "feature/e2e".into(),
-            cleanup_on_kill: true,
-            create_branch: true,
-        }),
+        worktree: Some(worktree_spec(base.path(), "feature/e2e", true)),
     };
 
     let s = client.spawn_session(&req).await.expect("spawn worktree");
@@ -160,7 +161,7 @@ async fn kill_removes_clean_worktree() {
         "expected a worktree for feature/e2e under <repo>/worktrees, got: {worktrees:?}"
     );
 
-    push_to_throwaway_origin(base.path());
+    let _origin = throwaway_origin(base.path());
     client.kill_session(s.id).await.expect("kill");
 
     // Give the daemon a moment to remove the worktree, then verify.
@@ -199,12 +200,7 @@ async fn kill_refuses_worktree_with_uncommitted_changes() {
         command: "sleep 30".into(),
         env: HashMap::new(),
         metadata: HashMap::new(),
-        worktree: Some(WorktreeSpec {
-            base_repo: base.path().to_path_buf(),
-            branch: "feature/unsaved".into(),
-            cleanup_on_kill: true,
-            create_branch: true,
-        }),
+        worktree: Some(worktree_spec(base.path(), "feature/unsaved", true)),
     };
 
     let s = client.spawn_session(&req).await.expect("spawn worktree");
@@ -262,12 +258,7 @@ async fn spawn_on_existing_branch_checks_it_out() {
         command: "sleep 30".into(),
         env: HashMap::new(),
         metadata: HashMap::new(),
-        worktree: Some(WorktreeSpec {
-            base_repo: base.path().to_path_buf(),
-            branch: "feature/existing".into(),
-            cleanup_on_kill: true,
-            create_branch: false,
-        }),
+        worktree: Some(worktree_spec(base.path(), "feature/existing", false)),
     };
 
     let s = client
@@ -280,7 +271,7 @@ async fn spawn_on_existing_branch_checks_it_out() {
         "expected a worktree checked out at feature/existing, got: {worktrees:?}"
     );
 
-    push_to_throwaway_origin(base.path());
+    let _origin = throwaway_origin(base.path());
     client.kill_session(s.id).await.expect("kill");
 }
 
@@ -328,7 +319,7 @@ async fn spawn_new_branch_creates_worktree_and_runs_in_it() {
     )
     .await;
 
-    push_to_throwaway_origin(base.path());
+    let _origin = throwaway_origin(base.path());
     client.kill_session(s.id).await.expect("kill");
 }
 
@@ -376,7 +367,7 @@ async fn second_spawn_on_same_branch_is_rejected() {
         "original worktree must be untouched"
     );
 
-    push_to_throwaway_origin(base.path());
+    let _origin = throwaway_origin(base.path());
     client.kill_session(first.id).await.expect("kill");
 }
 
@@ -419,10 +410,481 @@ async fn spawn_from_linked_worktree_places_in_main_checkout() {
         "worktrees must never nest inside another worktree"
     );
 
-    push_to_throwaway_origin(base.path());
+    let _origin = throwaway_origin(base.path());
     client.kill_session(s.id).await.expect("kill");
 }
 
+// ---------------------------------------------------------------------------
+// Worktree lifecycle: collisions, retention, reclaim (#88)
+// ---------------------------------------------------------------------------
+
+/// #77/#88: the target path `<repo>/worktrees/<branch>` is occupied by a real
+/// registered worktree the operator made by hand. The daemon sidesteps to the
+/// suffixed directory and never touches the occupant — and both trees keep
+/// working: two registered worktrees, two sessions, each running in its own.
+#[tokio::test(flavor = "multi_thread")]
+async fn occupied_path_gets_suffixed_directory_and_both_worktrees_work() {
+    let (_daemon, client) = bring_up().await;
+
+    let base = TempDir::new().unwrap();
+    init_repo(base.path());
+
+    // An operator-made worktree sits exactly where `feature/collide` would go.
+    // Its branch is a different one, so the requested branch stays creatable.
+    let squatter = base
+        .path()
+        .join("worktrees")
+        .join("feature")
+        .join("collide");
+    run_git(
+        &[
+            "worktree",
+            "add",
+            "-q",
+            "-b",
+            "operator/manual",
+            &squatter.to_string_lossy(),
+        ],
+        base.path(),
+    );
+
+    let s = client
+        .spawn_session(&worktree_req(base.path(), "feature/collide", true))
+        .await
+        .expect("spawn onto occupied path");
+
+    let suffixed = base
+        .path()
+        .join("worktrees")
+        .join("feature")
+        .join("collide-2");
+    assert_eq!(
+        s.cwd, suffixed,
+        "the daemon must take the suffixed directory, not the occupied one"
+    );
+    assert!(suffixed.is_dir(), "suffixed worktree must exist on disk");
+
+    // Both trees are registered, distinct, and the squatter is byte-intact.
+    let registrations = git_worktree_list(base.path());
+    assert!(
+        registrations
+            .iter()
+            .any(|l| l == &format!("worktree {}", squatter.canonicalize().unwrap().display())),
+        "operator's worktree must stay registered: {registrations:?}"
+    );
+    assert!(
+        registrations.iter().any(|l| l.contains("collide-2")),
+        "suffixed worktree must be registered too: {registrations:?}"
+    );
+
+    // Both sessions run inside their own tree at the same time.
+    let sessions = client.list_sessions().await.expect("list");
+    assert!(
+        sessions.iter().any(|x| x.id == s.id && x.cwd == suffixed),
+        "session must keep running in its suffixed tree"
+    );
+
+    let _origin = throwaway_origin(base.path());
+    client.kill_session(s.id).await.expect("kill");
+
+    // Only the daemon-made trees go; the operator's manual one survives.
+    let after = git_worktree_list(base.path());
+    assert!(
+        after
+            .iter()
+            .any(|l| l == &format!("worktree {}", squatter.canonicalize().unwrap().display())),
+        "operator's worktree must outlive the sessions: {after:?}"
+    );
+}
+
+/// #77/#88: the target path holds a plain directory the daemon never made and
+/// git has never heard of. The daemon neither adopts it nor errors — it builds
+/// beside it and leaves every byte of it alone.
+#[tokio::test(flavor = "multi_thread")]
+async fn foreign_directory_is_sidestepped_never_adopted() {
+    let (_daemon, client) = bring_up().await;
+
+    let base = TempDir::new().unwrap();
+    init_repo(base.path());
+
+    let squatter = base
+        .path()
+        .join("worktrees")
+        .join("feature")
+        .join("foreign");
+    std::fs::create_dir_all(&squatter).unwrap();
+    std::fs::write(squatter.join("operator-notes.txt"), b"mine\n").unwrap();
+
+    let s = client
+        .spawn_session(&worktree_req(base.path(), "feature/foreign", true))
+        .await
+        .expect("spawn must sidestep, not adopt or fail");
+
+    let suffixed = base
+        .path()
+        .join("worktrees")
+        .join("feature")
+        .join("foreign-2");
+    assert_eq!(s.cwd, suffixed, "session must run in the suffixed tree");
+    assert_eq!(
+        std::fs::read(squatter.join("operator-notes.txt")).unwrap(),
+        b"mine\n",
+        "the foreign directory must be untouched"
+    );
+    let registrations = git_worktree_list(base.path());
+    let registered_paths: Vec<&str> = registrations
+        .iter()
+        .filter_map(|l| l.strip_prefix("worktree "))
+        .collect();
+    assert!(
+        !registered_paths
+            .iter()
+            .any(|p| *p == squatter.canonicalize().unwrap().display().to_string()),
+        "a plain directory must never be adopted as a worktree: {registered_paths:?}"
+    );
+
+    let _origin = throwaway_origin(base.path());
+    client.kill_session(s.id).await.expect("kill");
+    assert!(squatter.join("operator-notes.txt").exists());
+}
+
+/// #79/#88: killing with uncommitted changes is refused; committing and
+/// pushing that work clears the guard and the very same kill then succeeds
+/// and removes the tree. The session is the handle on the work: while it is
+/// unsaved the session stays, once it is saved the tree goes.
+#[tokio::test(flavor = "multi_thread")]
+async fn guarded_kill_then_commit_and_push_makes_the_same_kill_succeed() {
+    let (_daemon, client) = bring_up().await;
+
+    let base = TempDir::new().unwrap();
+    init_repo(base.path());
+    let _origin = throwaway_origin(base.path());
+
+    let wt = base.path().join("worktrees").join("feature").join("guard");
+    let s = client
+        .spawn_session(&worktree_req(base.path(), "feature/guard", true))
+        .await
+        .expect("spawn");
+    std::fs::write(wt.join("README"), b"work in progress\n").unwrap();
+
+    // Refused: the edit is uncommitted.
+    let err = client
+        .kill_session(s.id)
+        .await
+        .expect_err("kill must refuse");
+    match err {
+        maestro_e2e::ClientError::Api(maestro_protocol::ClientError::Api { info, .. }) => {
+            assert_eq!(info.code, "kill_guarded", "{info:?}");
+            let breakdown = info.unsaved_work.expect("breakdown on the wire");
+            assert_eq!(breakdown.uncommitted_files, 1);
+            assert_eq!(breakdown.unpushed_commits, 0);
+        }
+        other => panic!("expected a kill_guarded refusal, got {other:?}"),
+    }
+    assert!(
+        client
+            .list_sessions()
+            .await
+            .unwrap()
+            .iter()
+            .any(|x| x.id == s.id),
+        "a refused kill keeps the session running"
+    );
+    assert_eq!(
+        std::fs::read(wt.join("README")).unwrap(),
+        b"work in progress\n",
+        "the worktree is untouched by the refusal"
+    );
+
+    // The operator does exactly what the refusal asked for: save and push.
+    commit_all(&wt, "wip");
+    push_all(base.path());
+
+    client.kill_session(s.id).await.expect("kill after saving");
+
+    let deadline = Instant::now() + Duration::from_secs(5);
+    while Instant::now() < deadline {
+        if !wt.exists() {
+            break;
+        }
+        tokio::time::sleep(Duration::from_millis(100)).await;
+    }
+    assert!(
+        !wt.exists(),
+        "a cleared worktree must be removed after kill"
+    );
+    let registrations = git_worktree_list(base.path());
+    assert!(
+        !registrations.iter().any(|l| l.contains("feature/guard")),
+        "removal must deregister the tree: {registrations:?}"
+    );
+}
+
+/// #81/#88: commits that no remote has refuse the kill; `--force` ends the
+/// session anyway but RETAINS the worktree — force never destroys blocked
+/// work, it parks it in the retained store with reason `force-killed`.
+#[tokio::test(flavor = "multi_thread")]
+async fn unpushed_commits_block_kill_and_force_retains_the_tree() {
+    let (_daemon, client) = bring_up().await;
+
+    let base = TempDir::new().unwrap();
+    init_repo(base.path());
+    let _origin = throwaway_origin(base.path());
+
+    let wt = base.path().join("worktrees").join("feature").join("local");
+    let s = client
+        .spawn_session(&worktree_req(base.path(), "feature/local", true))
+        .await
+        .expect("spawn");
+    std::fs::write(wt.join("README"), b"local only\n").unwrap();
+    commit_all(&wt, "not pushed yet");
+
+    // Refused: the commit is on no remote-tracking ref.
+    let err = client
+        .kill_session(s.id)
+        .await
+        .expect_err("kill must refuse");
+    match err {
+        maestro_e2e::ClientError::Api(maestro_protocol::ClientError::Api { info, .. }) => {
+            assert_eq!(info.code, "kill_guarded", "{info:?}");
+            let breakdown = info.unsaved_work.expect("breakdown on the wire");
+            assert_eq!(breakdown.unpushed_commits, 1);
+            assert_eq!(breakdown.uncommitted_files, 0);
+        }
+        other => panic!("expected a kill_guarded refusal, got {other:?}"),
+    }
+
+    // Force overrides the refusal and nothing else: session gone, tree kept.
+    let outcome = client.kill_session_forced(s.id).await.expect("forced kill");
+    let retained = outcome
+        .retained
+        .expect("force must retain the guarded tree");
+    assert_eq!(
+        retained.reason,
+        maestro_protocol::RetainedReason::ForceKilled
+    );
+    assert_eq!(retained.path, wt);
+    assert_eq!(retained.branch, "feature/local");
+    assert_eq!(retained.in_the_way.unpushed_commits, 1);
+
+    assert!(
+        !client
+            .list_sessions()
+            .await
+            .unwrap()
+            .iter()
+            .any(|x| x.id == s.id),
+        "the forced kill ends the session"
+    );
+    assert!(wt.is_dir(), "a force-retained worktree must stay on disk");
+    assert!(
+        git_worktree_list(base.path())
+            .iter()
+            .any(|l| l.contains("feature/local")),
+        "the retained tree stays registered in git"
+    );
+}
+
+/// #82/#88: a session that exits on its own never reaches the kill path, but
+/// its worktree follows the same rule. Dirty → retained with reason
+/// `exited-with-unsaved-work`; pristine → removed, leaving nothing behind.
+#[tokio::test(flavor = "multi_thread")]
+async fn natural_exit_settles_dirty_and_pristine_worktrees_differently() {
+    let (_daemon, client) = bring_up().await;
+
+    // Two repos so the two cases cannot see each other's state.
+    let dirty_repo = TempDir::new().unwrap();
+    init_repo(dirty_repo.path());
+    let _origin = throwaway_origin(dirty_repo.path());
+    let pristine_repo = TempDir::new().unwrap();
+    init_repo(pristine_repo.path());
+    let _origin_pristine = throwaway_origin(pristine_repo.path());
+
+    let dirty_wt = dirty_repo
+        .path()
+        .join("worktrees")
+        .join("feature")
+        .join("messy");
+    let pristine_wt = pristine_repo
+        .path()
+        .join("worktrees")
+        .join("feature")
+        .join("tidy");
+
+    let _dirty = client
+        .spawn_session(&CreateSessionRequest {
+            cwd: dirty_repo.path().to_path_buf(),
+            command: "sh -c 'echo unsaved > scratch.txt'".into(),
+            env: HashMap::new(),
+            metadata: HashMap::new(),
+            worktree: Some(worktree_spec(dirty_repo.path(), "feature/messy", true)),
+        })
+        .await
+        .expect("spawn dirty");
+    let _pristine = client
+        .spawn_session(&create_req_cmd(
+            pristine_repo.path(),
+            "true",
+            "feature/tidy",
+        ))
+        .await
+        .expect("spawn pristine");
+
+    assert!(dirty_wt.is_dir() && pristine_wt.is_dir());
+
+    // The watcher reaps dead tmux sessions every couple of ticks and settles
+    // each worktree accordingly. Poll for both outcomes.
+    wait_for_async(
+        "dirty exit retains its worktree",
+        Duration::from_secs(20),
+        || {
+            let client = client.clone();
+            let path = dirty_wt.clone();
+            async move {
+                client
+                    .list_worktrees()
+                    .await
+                    .ok()
+                    .map(|wts| {
+                        wts.iter().any(|w| {
+                            w.path == path
+                                && w.reason
+                                    == maestro_protocol::RetainedReason::ExitedWithUnsavedWork
+                        })
+                    })
+                    .unwrap_or(false)
+            }
+        },
+    )
+    .await;
+    wait_for_async(
+        "pristine exit removes its worktree entirely",
+        Duration::from_secs(20),
+        || {
+            let client = client.clone();
+            let repo = pristine_repo.path().to_path_buf();
+            let path = pristine_wt.clone();
+            async move {
+                if path.exists() {
+                    return false;
+                }
+                let listed = client.list_worktrees().await.ok();
+                let listed_clear = listed
+                    .map(|wts| !wts.iter().any(|w| w.path == path))
+                    .unwrap_or(false);
+                let registered = git_worktree_list(&repo);
+                !registered.iter().any(|l| l.contains("feature/tidy")) && listed_clear
+            }
+        },
+    )
+    .await;
+
+    // The dirty tree is still fully there, file included.
+    assert!(dirty_wt.is_dir());
+    assert_eq!(
+        std::fs::read(dirty_wt.join("scratch.txt")).unwrap(),
+        b"unsaved\n"
+    );
+}
+
+fn create_req_cmd(cwd: &std::path::Path, command: &str, branch: &str) -> CreateSessionRequest {
+    CreateSessionRequest {
+        cwd: cwd.to_path_buf(),
+        command: command.into(),
+        env: HashMap::new(),
+        metadata: HashMap::new(),
+        worktree: Some(worktree_spec(cwd, branch, true)),
+    }
+}
+
+/// #80/#88: `GET /api/worktrees` lists what the daemon is holding, with the
+/// reason and a live in-the-way breakdown; reclaim removes the directory and
+/// the store entry but NEVER the branch — its commits outlive the reclaim.
+#[tokio::test(flavor = "multi_thread")]
+async fn worktrees_endpoint_lists_reasons_and_reclaim_keeps_the_branch() {
+    let (_daemon, client) = bring_up().await;
+
+    let base = TempDir::new().unwrap();
+    init_repo(base.path());
+    let _origin = throwaway_origin(base.path());
+
+    let wt = base.path().join("worktrees").join("feature").join("parked");
+    let s = client
+        .spawn_session(&worktree_req(base.path(), "feature/parked", true))
+        .await
+        .expect("spawn");
+    std::fs::write(wt.join("README"), b"worth keeping\n").unwrap();
+    commit_all(&wt, "worth keeping");
+    let sha = branch_sha(&wt, "feature/parked");
+
+    let outcome = client.kill_session_forced(s.id).await.expect("force kill");
+    assert!(outcome.retained.is_some());
+
+    let listed = client.list_worktrees().await.expect("list worktrees");
+    assert_eq!(listed.len(), 1, "exactly one retained entry: {listed:?}");
+    let entry = &listed[0];
+    assert_eq!(entry.path, wt);
+    assert_eq!(entry.branch, "feature/parked");
+    assert_eq!(entry.reason, maestro_protocol::RetainedReason::ForceKilled);
+    assert_eq!(entry.in_the_way.unpushed_commits, 1);
+
+    client.reclaim_worktree(entry.id).await.expect("reclaim");
+    assert!(!wt.exists(), "reclaim removes the directory");
+    assert!(
+        client.list_worktrees().await.unwrap().is_empty(),
+        "reclaim drops the store entry"
+    );
+
+    // The whole point of reclaim: the branch and its commits survive.
+    assert_eq!(
+        branch_sha(base.path(), "feature/parked"),
+        sha,
+        "the branch must keep pointing at the same commit after reclaim"
+    );
+}
+
+/// The retained store is state-dir backed (#80): a daemon restart must not
+/// orphan the trees it is holding — they are still on disk with entries
+/// pointing at them, and still reclaimable afterwards.
+#[tokio::test(flavor = "multi_thread")]
+async fn retained_store_survives_a_daemon_restart() {
+    let (mut daemon, client) = bring_up().await;
+
+    let base = TempDir::new().unwrap();
+    init_repo(base.path());
+    let _origin = throwaway_origin(base.path());
+
+    let wt = base
+        .path()
+        .join("worktrees")
+        .join("feature")
+        .join("durable");
+    let s = client
+        .spawn_session(&worktree_req(base.path(), "feature/durable", true))
+        .await
+        .expect("spawn");
+    std::fs::write(wt.join("README"), b"survives restarts\n").unwrap();
+    commit_all(&wt, "survives restarts");
+    client.kill_session_forced(s.id).await.expect("force kill");
+
+    daemon.restart().await;
+
+    let listed = client.list_worktrees().await.expect("list after restart");
+    assert_eq!(listed.len(), 1, "store must survive restart: {listed:?}");
+    assert_eq!(listed[0].path, wt);
+    assert_eq!(
+        listed[0].reason,
+        maestro_protocol::RetainedReason::ForceKilled
+    );
+    assert!(wt.is_dir(), "the tree itself must survive the restart too");
+
+    client
+        .reclaim_worktree(listed[0].id)
+        .await
+        .expect("reclaim");
+    assert!(!wt.exists());
+}
+
 // ---------------------------------------------------------------------------
 // GET /api/projects + /api/branches (#54/#55/#66)
 // ---------------------------------------------------------------------------
@@ -788,10 +1250,12 @@ fn git_worktree_list(dir: &std::path::Path) -> Vec<String> {
         .collect()
 }
 
-/// Push every branch of `repo` to a throwaway bare remote, so its commits are
-/// reachable from remote-tracking refs. Without one the kill guard (#79)
-/// reads every commit as unpushed, and any worktree session refuses to die.
-fn push_to_throwaway_origin(repo: &std::path::Path) {
+/// Bare remote registered as `origin` on `repo`, seeded with every current
+/// branch, so existing commits are reachable from remote-tracking refs.
+/// Without one the kill guard (#79) reads every commit as unpushed, and any
+/// worktree session refuses to die. The caller must keep the `TempDir` alive
+/// while the remote is still needed; later pushes go through [`push_all`].
+fn throwaway_origin(repo: &std::path::Path) -> TempDir {
     let origin = tempfile::TempDir::new().unwrap();
     run_git(
         &["init", "-q", "--bare", origin.path().to_str().unwrap()],
@@ -803,9 +1267,34 @@ fn push_to_throwaway_origin(repo: &std::path::Path) {
         .args(["remote", "add", "origin", origin.path().to_str().unwrap()])
         .output()
         .expect("git remote add");
+    push_all(repo);
+    origin
+}
+
+fn push_all(repo: &std::path::Path) {
     run_git(&["push", "-q", "--all", "origin"], repo);
 }
 
+fn commit_all(dir: &std::path::Path, message: &str) {
+    run_git(&["add", "-A"], dir);
+    run_git(&["commit", "-q", "-m", message], dir);
+}
+
+fn branch_sha(repo: &std::path::Path, branch: &str) -> String {
+    let out = Command::new("git")
+        .arg("-C")
+        .arg(repo)
+        .args(["rev-parse", "--verify", &format!("refs/heads/{branch}")])
+        .output()
+        .expect("git rev-parse");
+    assert!(
+        out.status.success(),
+        "branch {branch} missing: {}",
+        String::from_utf8_lossy(&out.stderr)
+    );
+    String::from_utf8_lossy(&out.stdout).trim().to_string()
+}
+
 #[tokio::test(flavor = "multi_thread")]
 async fn daemon_events_ws_streams_snapshot_then_session_added() {
     // NAP-248: subscribe to the daemon's WS /api/events, expect an initial

crates/maestro-protocol/src/client.rs

@@ -16,7 +16,7 @@ use uuid::Uuid;
 use crate::routes::{self, UrlError};
 use crate::{
     ApiError, BranchInfo, CreateSessionRequest, DaemonInfo, DirListing, ErrorInfo, GitRoot,
-    Project, RecentDirs, RetainedWorktree, Session,
+    KillOutcome, Project, RecentDirs, RetainedWorktree, Session,
 };
 
 /// Time budget for establishing a TCP connection to the daemon.
@@ -114,12 +114,24 @@ impl DaemonClient {
         self.post(routes::SESSIONS, req).await
     }
 
-    pub async fn kill_session(&self, id: Uuid) -> Result<(), ClientError> {
+    /// Kill a session. With `force`, the daemon overrides the kill refusal
+    /// (#79) and retains the worktree instead of removing it (#81); the
+    /// outcome then names what was kept and where.
+    pub async fn kill_session(&self, id: Uuid, force: bool) -> Result<KillOutcome, ClientError> {
+        let query: &[(&str, &str)] = if force {
+            &[(routes::FORCE_QUERY, "true")]
+        } else {
+            &[]
+        };
         let resp = self
-            .send(Method::DELETE, &routes::session(id), &[], None::<&()>)
+            .send(Method::DELETE, &routes::session(id), query, None::<&()>)
             .await?;
-        check(resp).await?;
-        Ok(())
+        let resp = check(resp).await?;
+        // An unforced kill keeps its historical `204 No Content`.
+        if resp.status() == reqwest::StatusCode::NO_CONTENT {
+            return Ok(KillOutcome { retained: None });
+        }
+        json(resp).await
     }
 
     pub async fn daemon_info(&self) -> Result<DaemonInfo, ClientError> {

crates/maestro-protocol/src/lib.rs

@@ -80,6 +80,13 @@ pub struct Session {
     /// from daemons that predate the field.
     #[serde(default = "epoch")]
     pub last_activity_at: DateTime<Utc>,
+    /// Wall-clock time at which the session entered its current
+    /// [`ActivityState`] (#102) — how long it has been `Active`, `Idle` or
+    /// `AwaitingInput`. Distinct from [`Self::last_activity_at`], which only
+    /// tracks the last observed PTY output. Populated by #104; defaults to the
+    /// Unix epoch on payloads from daemons that predate the field.
+    #[serde(default = "epoch")]
+    pub activity_since: DateTime<Utc>,
     /// The pane's *current* working directory (`#{pane_current_path}`) — distinct
     /// from [`Session::cwd`], the directory it was spawned in. The activity
     /// watcher refreshes it as the user `cd`s around; it drives the web UI's
@@ -87,6 +94,13 @@ pub struct Session {
     /// from daemons that predate the field.
     #[serde(default)]
     pub current_cwd: Option<PathBuf>,
+    /// Whether the session's worktree currently holds anything that would
+    /// block an unforced kill (#83), summarised by [`InTheWay`]'s `Display`.
+    /// Refreshed by the daemon's watcher; `None` for sessions without a
+    /// worktree and until the first probe. Defaults on the wire so payloads
+    /// from daemons that predate the field stay forward-compatible.
+    #[serde(default)]
+    pub blocked_work: Option<InTheWay>,
 }
 
 /// Default for [`Session::last_activity_at`] when an older payload omits it.
@@ -103,7 +117,12 @@ pub enum SessionStatus {
 /// Inferred session activity, orthogonal to [`SessionStatus`] (NAP-340). The
 /// daemon derives this from tmux pane state, PTY quiescence, and `/proc`
 /// inspection — never by parsing the terminal byte stream.
-#[derive(Debug, Clone, Copy, PartialEq, Eq, Serialize, Deserialize, Default)]
+///
+/// Deserializes leniently (#110, SIDEBAR.md Precedence): an unknown variant
+/// from a newer daemon becomes [`ActivityState::Idle`] instead of failing the
+/// whole `Session`. Non-string values still error — only variant names are
+/// forgiven.
+#[derive(Debug, Clone, Copy, PartialEq, Eq, Serialize, Default)]
 pub enum ActivityState {
     /// Producing output, or the foreground process is busy.
     Active,
@@ -112,6 +131,25 @@ pub enum ActivityState {
     Idle,
     /// Blocked on a `read()` from the pty — waiting on the user.
     AwaitingInput,
+    /// The agent running in the session reported a failure (#102). Never
+    /// inferred by the daemon; only set when an agent reports it (#105).
+    Error,
+}
+
+impl<'de> Deserialize<'de> for ActivityState {
+    fn deserialize<D>(deserializer: D) -> Result<Self, D::Error>
+    where
+        D: serde::Deserializer<'de>,
+    {
+        let s = String::deserialize(deserializer)?;
+        Ok(match s.as_str() {
+            "Active" => Self::Active,
+            "AwaitingInput" => Self::AwaitingInput,
+            "Error" => Self::Error,
+            // Known or not, any other spelling degrades to the neutral default
+            _ => Self::Idle,
+        })
+    }
 }
 
 /// Optional worktree request attached to a `CreateSessionRequest`.
@@ -119,11 +157,6 @@ pub enum ActivityState {
 pub struct WorktreeSpec {
     pub base_repo: PathBuf,
     pub branch: String,
-    /// Kept on the wire for CLI compatibility (#56) but no longer a
-    /// user-facing choice: the daemon always cleans up on kill, guarded
-    /// against unsaved work. Defaults to `true`.
-    #[serde(default = "default_true")]
-    pub cleanup_on_kill: bool,
     /// When false, `branch` must already exist and is checked out as-is
     /// (#56); when true (the default, and what every payload meant before
     /// the field existed) the daemon creates it with `worktree add -b`.
@@ -195,6 +228,19 @@ pub struct RetainedWorktree {
     pub in_the_way: InTheWay,
 }
 
+/// Body of a successful forced `DELETE /api/sessions/:id?force=true` (#81).
+/// A forced kill ends the session and retains its worktree instead of
+/// removing it; this names what was kept, where, and why, so a client can say
+/// where the work went rather than leaving the operator to wonder.
+#[derive(Debug, Clone, PartialEq, Eq, Serialize, Deserialize)]
+pub struct KillOutcome {
+    /// Set when the worktree was retained with reason `force-killed`; `None`
+    /// when there was nothing to retain — no worktree at all, or one whose
+    /// guard was clear, which a forced kill removes as usual.
+    #[serde(default)]
+    pub retained: Option<RetainedWorktree>,
+}
+
 impl std::fmt::Display for InTheWay {
     /// "3 uncommitted files, 2 unpushed commits" — zero parts are omitted;
     /// all-zero renders "no unsaved work". This is the phrasing every client
@@ -522,7 +568,11 @@ mod tests {
             last_activity_at: DateTime::parse_from_rfc3339("2026-05-24T12:05:00Z")
                 .unwrap()
                 .with_timezone(&Utc),
+            activity_since: DateTime::parse_from_rfc3339("2026-05-24T12:04:30Z")
+                .unwrap()
+                .with_timezone(&Utc),
             current_cwd: Some(PathBuf::from("/home/naps62/projects/maestro/crates")),
+            blocked_work: None,
         }
     }
 
@@ -542,6 +592,63 @@ mod tests {
         assert_eq!(s.activity, ActivityState::Idle);
         assert_eq!(s.last_activity_at, epoch());
         assert!(s.current_cwd.is_none());
+        assert!(s.blocked_work.is_none());
+    }
+
+    #[test]
+    fn blocked_work_defaults_to_none_on_legacy_payload() {
+        // A pre-#83 daemon omits the indicator; it must deserialize to `None`
+        // rather than failing, and a present value round-trips.
+        let json = serde_json::json!({
+            "id": Uuid::from_u128(1),
+            "cwd": "/tmp",
+            "command": "bash",
+            "status": "Running",
+            "created_at": "2026-05-24T12:00:00Z"
+        });
+        let s: Session = serde_json::from_value(json).unwrap();
+        assert_eq!(s.blocked_work, None);
+
+        let mut with_blocker = sample_session();
+        with_blocker.blocked_work = Some(InTheWay {
+            uncommitted_files: 3,
+            ..InTheWay::default()
+        });
+        assert_eq!(
+            with_blocker.clone().blocked_work,
+            serde_json::from_value::<Session>(serde_json::to_value(&with_blocker).unwrap())
+                .unwrap()
+                .blocked_work
+        );
+    }
+
+    #[test]
+    fn activity_since_defaults_to_epoch_on_legacy_payload() {
+        // A daemon predating #102 omits `activity_since`; it must deserialize
+        // to the forward-compat default rather than failing, and a present
+        // value round-trips.
+        let json = serde_json::json!({
+            "id": Uuid::from_u128(1),
+            "cwd": "/tmp",
+            "command": "bash",
+            "status": "Running",
+            "created_at": "2026-05-24T12:00:00Z"
+        });
+        let s: Session = serde_json::from_value(json).unwrap();
+        assert_eq!(s.activity_since, epoch());
+
+        let full = sample_session();
+        assert_eq!(full, round_trip(&full));
+    }
+
+    // #102: nothing infers `Error`; only #105's agent-reported failure sets it.
+    #[test]
+    fn error_activity_state_serializes_pascal_case_and_idle_stays_default() {
+        assert_eq!(
+            serde_json::to_value(ActivityState::Error).unwrap(),
+            serde_json::json!("Error")
+        );
+        assert_eq!(ActivityState::default(), ActivityState::Idle);
     }
 
     #[test]
@@ -553,6 +660,35 @@ mod tests {
         assert_eq!(ActivityState::default(), ActivityState::Idle);
     }
 
+    // #110 / SIDEBAR.md Precedence: a future daemon may send an
+    // `ActivityState` variant this client does not know; it must degrade to
+    // the neutral default instead of failing the whole `Session`.
+    #[test]
+    fn unknown_activity_state_variant_deserializes_to_idle() {
+        assert_eq!(
+            serde_json::from_value::<ActivityState>(serde_json::json!("Teleported")).unwrap(),
+            ActivityState::Idle
+        );
+
+        let mut future = serde_json::to_value(sample_session()).unwrap();
+        future["activity"] = serde_json::json!("QuantumEntangled");
+        let s: Session = serde_json::from_value(future).unwrap();
+        assert_eq!(s.activity, ActivityState::Idle);
+    }
+
+    #[test]
+    fn non_string_activity_payload_still_fails_deserialization() {
+        let json = serde_json::json!({
+            "id": Uuid::from_u128(1),
+            "cwd": "/tmp",
+            "command": "bash",
+            "status": "Running",
+            "created_at": "2026-05-24T12:00:00Z",
+            "activity": 42,
+        });
+        assert!(serde_json::from_value::<Session>(json).is_err());
+    }
+
     #[test]
     fn session_round_trips() {
         let s = sample_session();
@@ -581,7 +717,6 @@ mod tests {
             worktree: Some(WorktreeSpec {
                 base_repo: PathBuf::from("/home/naps62/projects/maestro"),
                 branch: "feat/foo".into(),
-                cleanup_on_kill: true,
                 create_branch: true,
             }),
         };
@@ -611,7 +746,6 @@ mod tests {
         });
         let spec: WorktreeSpec = serde_json::from_value(json).unwrap();
         assert!(spec.create_branch);
-        assert!(spec.cleanup_on_kill);
     }
 
     #[test]
@@ -619,7 +753,6 @@ mod tests {
         let spec = WorktreeSpec {
             base_repo: PathBuf::from("/work"),
             branch: "feat/foo".into(),
-            cleanup_on_kill: true,
             create_branch: false,
         };
         assert_eq!(spec, round_trip(&spec));
@@ -679,6 +812,22 @@ mod tests {
         );
     }
 
+    #[test]
+    fn kill_outcome_round_trips_a_retained_worktree() {
+        let outcome = KillOutcome {
+            retained: Some(sample_retained_worktree()),
+        };
+        assert_eq!(outcome, round_trip(&outcome));
+    }
+
+    /// A kill with nothing to retain — no worktree, or a clean one removed as
+    /// usual — decodes from an absent field.
+    #[test]
+    fn kill_outcome_defaults_to_nothing_retained() {
+        let outcome: KillOutcome = serde_json::from_value(serde_json::json!({})).unwrap();
+        assert_eq!(outcome.retained, None);
+    }
+
     #[test]
     fn catalog_event_round_trips_and_tags() {
         let session = sample_session();

crates/maestro-protocol/src/routes.rs

@@ -38,6 +38,10 @@ pub const PATH_QUERY: &str = "path";
 /// Name of the query parameter [`NAMES`] takes.
 pub const COUNT_QUERY: &str = "count";
 
+/// Name of the boolean query parameter `DELETE /api/sessions/:id` takes (#81).
+/// `force=true` overrides the kill refusal and retains the worktree.
+pub const FORCE_QUERY: &str = "force";
+
 /// `DELETE /api/sessions/:id`.
 pub fn session(id: Uuid) -> String {
     format!("{SESSIONS}/{id}")

crates/maestro-testing/src/lib.rs

@@ -42,7 +42,9 @@ pub fn session(id: Uuid, cwd: &str, command: &str) -> Session {
         foreground: None,
         activity: Default::default(),
         last_activity_at: Utc::now(),
+        activity_since: chrono::Utc::now(),
         current_cwd: None,
+        blocked_work: None,
     }
 }
 

crates/maestro-tui/src/app.rs

@@ -175,7 +175,8 @@ impl App {
                     // Render on next loop iteration.
                 }
                 _ = tokio::time::sleep(Duration::from_millis(33)) => {
-                    // 30 Hz heartbeat.
+                    let effects = self.poll_due_probes_at(std::time::Instant::now());
+                    self.perform(effects).await;
                 }
             }
         }
@@ -439,7 +440,7 @@ impl App {
         if draft.take_name_refill() {
             effects.push(Effect::RefillNames(tab_idx));
         }
-        if let Some((seq, path)) = draft.take_gitroot_probe() {
+        if let Some((seq, path)) = draft.take_gitroot_probe(std::time::Instant::now()) {
             effects.push(Effect::ProbeGitRoot {
                 tab: tab_idx,
                 seq,
@@ -452,6 +453,26 @@ impl App {
         effects
     }
 
+    /// Fire any draft gitroot probes whose debounce window has elapsed (#74).
+    /// The 30 Hz heartbeat calls this so a burst of typing issues its one
+    /// probe even after the last keystroke.
+    fn poll_due_probes_at(&mut self, now: std::time::Instant) -> Vec<Effect> {
+        let mut effects = Vec::new();
+        for tab_idx in 0..self.state.tabs.len() {
+            let Some(PaneRef::Draft(draft)) = self.state.tabs[tab_idx].pane.as_mut() else {
+                continue;
+            };
+            if let Some((seq, path)) = draft.take_gitroot_probe(now) {
+                effects.push(Effect::ProbeGitRoot {
+                    tab: tab_idx,
+                    seq,
+                    path,
+                });
+            }
+        }
+        effects
+    }
+
     /// Populate a freshly opened draft: presets from `/api/info` (falling back
     /// to the built-ins already in place), projects from `/api/projects`, and
     /// a first name batch. Applies only if that tab still shows the draft —
@@ -733,8 +754,14 @@ impl App {
     }
 
     async fn submit_kill(&mut self, sid: Uuid) {
-        match self.daemon.kill_session(sid).await {
-            Ok(()) => self.release_session(sid),
+        match self.daemon.kill_session(sid, false).await {
+            Ok(outcome) => {
+                if let Some(w) = outcome.retained {
+                    self.state
+                        .toast(format!("worktree retained: {}", w.path.display()));
+                }
+                self.release_session(sid)
+            }
             Err(e) => self.state.toast(format!("kill failed: {e}")),
         }
     }
@@ -1100,7 +1127,9 @@ mod tests {
                 foreground: None,
                 activity: Default::default(),
                 last_activity_at: Utc::now(),
+                activity_since: chrono::Utc::now(),
                 current_cwd: None,
+                blocked_work: None,
             }],
         });
         app.dispatch(Action::SidebarNext);
@@ -1321,9 +1350,7 @@ mod tests {
         for c in "crimson-otter".chars() {
             app.handle_draft_input(&InputKey::char(c));
         }
-        app.handle_draft_input(&InputKey::Tab); // → worktree toggle
-        app.handle_draft_input(&InputKey::Tab); // → branch mode
-        app.handle_draft_input(&InputKey::Tab); // → new-branch name
+        app.handle_draft_input(&InputKey::Tab); // → advanced disclosure (collapsed, #93)
         app.handle_draft_input(&InputKey::Tab); // → submit
 
         match app.handle_draft_input(&InputKey::Enter).as_slice() {
@@ -1340,10 +1367,11 @@ mod tests {
         }
     }
 
-    /// Editing the raw path with the worktree toggle on schedules a
-    /// `/api/gitroot` probe so the section learns its base repo (#65).
+    /// Editing the raw path schedules a `/api/gitroot` probe only once the
+    /// keystroke burst settles (#74): nothing fires inside the debounce
+    /// window; the heartbeat picks the due probe up afterwards.
     #[test]
-    fn typing_a_raw_path_schedules_a_gitroot_probe() {
+    fn typing_a_raw_path_schedules_a_debounced_gitroot_probe() {
         let mut app = make_app();
         app.dispatch(Action::NewDraftPane);
         let PaneRef::Draft(draft) = app.state.active_tab_mut().pane.as_mut().unwrap() else {
@@ -1352,13 +1380,24 @@ mod tests {
         draft.cwd_raw_visible = true;
         draft.focused_field = DraftField::CwdRaw;
 
-        let effects = app.handle_draft_input(&InputKey::char('/'));
+        // A burst of keystrokes fires nothing.
+        for c in "/opt/tooling".chars() {
+            assert!(app.handle_draft_input(&InputKey::char(c)).is_empty());
+            assert!(app.poll_due_probes_at(std::time::Instant::now()).is_empty());
+        }
+
+        // Once the quiet period passes, exactly one probe is due.
+        let due = std::time::Instant::now()
+            + std::time::Duration::from_millis(crate::draft::GITROOT_PROBE_DEBOUNCE_MS) * 10;
+        match app.poll_due_probes_at(due).as_slice() {
+            [Effect::ProbeGitRoot { tab: 0, path, .. }] => {
+                assert_eq!(path, &std::path::PathBuf::from("/opt/tooling"));
+            }
+            other => panic!("expected one ProbeGitRoot effect, got {other:?}"),
+        }
         assert!(
-            matches!(
-                effects.as_slice(),
-                [Effect::ProbeGitRoot { tab: 0, seq: 2, .. }]
-            ),
-            "{effects:?}"
+            app.poll_due_probes_at(due).is_empty(),
+            "the probe is consumed once"
         );
     }
 
@@ -1513,8 +1552,8 @@ mod tests {
             panic!("expected a draft pane");
         };
         assert_eq!(draft.command(), "aider");
-        assert_eq!(draft.rows.len(), 1);
-        assert_eq!(draft.rows[0].project.name, "maestro");
+        assert_eq!(draft.groups.len(), 1);
+        assert_eq!(draft.groups[0].main.name, "maestro");
         assert_eq!(draft.home_dir, "/home/u");
         assert_eq!(draft.name.value(), "crimson-otter");
     }
@@ -1606,8 +1645,10 @@ mod tests {
                 foreground: None,
                 activity: Default::default(),
                 last_activity_at: chrono::Utc::now(),
+                activity_since: chrono::Utc::now(),
 
                 current_cwd: None,
+                blocked_work: None,
             }],
         });
         app.dispatch(Action::KillHighlighted);

crates/maestro-tui/src/catalog.rs

@@ -194,7 +194,9 @@ mod tests {
             foreground: None,
             activity: Default::default(),
             last_activity_at: chrono::Utc::now(),
+            activity_since: chrono::Utc::now(),
             current_cwd: None,
+            blocked_work: None,
         }
     }
 

crates/maestro-tui/src/config.rs

@@ -238,6 +238,26 @@ mod tests {
         assert!(s.contains("ctrl-glorb"), "diagnostic: {s}");
     }
 
+    /// Regression for #70: the previous canonical form of a real Shift+S
+    /// keypress was `"shift-S"`, which the default `"S"` binding never
+    /// matched. Drive the actual crossterm event, not the binding string,
+    /// so the dead-key bug can't come back unnoticed.
+    #[test]
+    fn real_shift_s_keypress_resolves_to_fast_forward_spawn() {
+        use crossterm::event::{Event as CtEvent, KeyCode, KeyEvent, KeyModifiers};
+
+        use crate::input::{canonicalise, Region};
+
+        let cfg = TuiConfig::load(&TuiSection::default()).unwrap();
+        let ev = CtEvent::Key(KeyEvent::new(KeyCode::Char('S'), KeyModifiers::SHIFT));
+        let key = canonicalise(&ev, |_, _| Region::Unknown).expect("key event canonicalises");
+
+        assert_eq!(
+            cfg.keymap.resolve(Mode::Normal, &key.canonical()),
+            Some(Action::FastForwardSpawn),
+        );
+    }
+
     #[test]
     fn custom_chord_timeout_is_applied() {
         let mut section = TuiSection::default();

crates/maestro-tui/src/fast_forward.rs

@@ -80,7 +80,6 @@ impl FastForwardDefaults {
                     .clone()
                     .unwrap_or_else(|| project.path.clone()),
                 branch: name.to_string(),
-                cleanup_on_kill: true,
                 create_branch: true,
             }),
         })

crates/maestro-tui/src/input.rs

@@ -117,7 +117,9 @@ impl InputKey {
                 if *alt {
                     out.push_str("alt-");
                 }
-                if *shift {
+                // Uppercase already implies shift; crossterm sets the flag
+                // on every such char, so skip the redundant prefix (#70).
+                if *shift && !c.is_uppercase() {
                     out.push_str("shift-");
                 }
                 out.push(*c);
@@ -580,12 +582,28 @@ mod tests {
 
     #[test]
     fn canonical_round_trips_simple_chars() {
-        for s in ["a", "ctrl-a", "ctrl-w", "alt-x", "shift-A"] {
+        for s in ["a", "ctrl-a", "ctrl-w", "alt-x"] {
             let k = InputKey::parse(s).unwrap();
             assert_eq!(k.canonical(), s, "round-trip {s:?}");
         }
     }
 
+    /// crossterm 0.28 attaches `KeyModifiers::SHIFT` to any uppercase char,
+    /// so a real Shift+S delivers `Char { c: 'S', shift: true }`. Its
+    /// canonical form must be the bare `"S"` a keymap binds, not `"shift-S"` —
+    /// the uppercase letter already says "shifted"; a redundant prefix would
+    /// make the default `S` binding unreachable from the keyboard (#70).
+    #[test]
+    fn shift_flag_is_redundant_for_an_already_uppercase_char() {
+        let k = InputKey::Char {
+            c: 'S',
+            ctrl: false,
+            alt: false,
+            shift: true,
+        };
+        assert_eq!(k.canonical(), "S");
+    }
+
     #[test]
     fn canonical_round_trips_specials() {
         for s in [

crates/maestro-tui/src/overlays.rs

@@ -14,23 +14,28 @@ use ratatui::Frame;
 #[derive(Debug, Clone)]
 pub struct KillConfirm {
     pub label: String,
+    /// #83: what the daemon's watcher last saw in the worktree, phrased by
+    /// [`maestro_protocol::InTheWay`]'s Display — so "this will be refused"
+    /// is visible before the attempt. `None` while nothing blocks.
+    pub blockers: Option<String>,
 }
 
 impl KillConfirm {
     pub fn render(&self, f: &mut Frame, parent: Rect) {
-        let area = centered(parent, 50, 5);
+        let area = centered(parent, 60, if self.blockers.is_some() { 6 } else { 5 });
         f.render_widget(Clear, area);
         let block = Block::default().title(" kill ").borders(Borders::ALL);
         let inner = block.inner(area);
         f.render_widget(block, area);
-        f.render_widget(
-            Paragraph::new(vec![
-                Line::from(format!("Kill session {}?", self.label)),
-                Line::from(""),
-                Line::from("[y] yes   [n] no"),
-            ]),
-            inner,
-        );
+        let mut lines = vec![Line::from(format!("Kill session {}?", self.label))];
+        if let Some(blockers) = &self.blockers {
+            // Same phrasing the reclaim confirmation uses for its own guard.
+            lines.push(Line::from(format!("Currently in the way: {blockers}")));
+            lines.push(Line::from("The kill will be refused unless forced."));
+        }
+        lines.push(Line::from(""));
+        lines.push(Line::from("[y] yes   [n] no"));
+        f.render_widget(Paragraph::new(lines), inner);
     }
 }
 
@@ -121,6 +126,7 @@ mod tests {
     fn kill_confirm_renders_prompt() {
         let modal = KillConfirm {
             label: "session-7".into(),
+            blockers: None,
         };
         let rendered = render_to_string(60, 10, |f| modal.render(f, f.area()));
         assert!(rendered.contains("Kill"));
@@ -129,6 +135,22 @@ mod tests {
         assert!(rendered.contains("no"));
     }
 
+    /// #83: when the worktree blocks, the confirm names it before the
+    /// operator commits — in `InTheWay`'s own words.
+    #[test]
+    fn kill_confirm_names_what_blocks() {
+        let modal = KillConfirm {
+            label: "session-7".into(),
+            blockers: Some("2 uncommitted files".into()),
+        };
+        let rendered = render_to_string(70, 10, |f| modal.render(f, f.area()));
+        assert!(
+            rendered.contains("Currently in the way: 2 uncommitted files"),
+            "{rendered}"
+        );
+        assert!(rendered.contains("refused"), "{rendered}");
+    }
+
     #[test]
     fn help_overlay_lists_lines() {
         let help = HelpOverlay {

crates/maestro-tui/src/render.rs

@@ -146,8 +146,19 @@ pub fn draw(f: &mut Frame, inputs: RenderInputs<'_>) -> RegionMap {
 
     match inputs.state.overlay() {
         Some(OverlayKind::KillConfirm(id)) => {
+            // #83: surface what the watcher last saw in the worktree, in
+            // InTheWay's own words, before the operator commits to the kill.
+            let blockers = inputs
+                .sidebar
+                .sessions
+                .iter()
+                .find(|s| &s.id == id)
+                .and_then(|s| s.blocked_work)
+                .filter(|b| !b.is_clear())
+                .map(|b| b.to_string());
             let kc = KillConfirm {
                 label: id.to_string(),
+                blockers,
             };
             kc.render(f, area);
             map.modal = Some(area);

crates/maestro-tui/src/sidebar.rs

@@ -1,10 +1,14 @@
-//! Sidebar widget — session list, navigation-only.
+//! Sidebar widget — session cards per `docs/SIDEBAR.md`.
 //!
-//! Status glyphs: ● attached / ○ live / ✗ dead.
+//! Line 1: status glyph (● attached / ○ live / ✗ dead) + name.
+//! Line 2: activity dot + duration in the state's colour, plus the
+//! blocked-work and exited fragments when they apply. Absent entirely when
+//! it has nothing to say.
 
 use std::collections::HashSet;
 
-use maestro_protocol::{Session, SessionStatus};
+use chrono::Utc;
+use maestro_protocol::{ActivityState, Session, SessionStatus};
 use ratatui::layout::Rect;
 use ratatui::style::{Color, Modifier, Style};
 use ratatui::text::{Line, Span};
@@ -12,6 +16,32 @@ use ratatui::widgets::{Block, Borders, Paragraph};
 use ratatui::Frame;
 use uuid::Uuid;
 
+/// Time-in-state alone earns a meta line only once the session has sat in
+/// its current activity state this long (docs/SIDEBAR.md).
+const META_LINE_AFTER_SECS: i64 = 30;
+/// A payload predating #102 defaults `activity_since` to the Unix epoch. Per
+/// docs/SIDEBAR.md such a session contributes no duration — the dot still
+/// renders — so anything implausibly old counts as "never observed" rather
+/// than a card announcing that the session has been idle for half a century.
+/// Mirrors `PLAUSIBLE_EPOCH_MS` in `web/src/activity.ts`.
+const PLAUSIBLE_SINCE_YEAR: i32 = 2010;
+const INDENT: &str = "  ";
+const META_INDENT: &str = "    ";
+/// Spawn-similar and kill, shown on the highlighted card's top-right corner.
+const ACTIONS: &str = "⧉ ✕";
+
+/// Every card sits on this background so cards read as cards against the
+/// panel; the highlighted card swaps it for the focus background instead
+/// (`Modifier::REVERSED` made the card unreadable against a background).
+const CARD_BG: Color = Color::Black;
+fn card_base(highlighted: bool) -> Style {
+    if highlighted {
+        Style::default().fg(Color::Black).bg(Color::Cyan)
+    } else {
+        Style::default().bg(CARD_BG)
+    }
+}
+
 /// Renderable sidebar state.
 #[derive(Debug, Clone)]
 pub struct Sidebar {
@@ -41,29 +71,171 @@ impl Sidebar {
         let inner = block.inner(area);
         f.render_widget(block, area);
 
+        let width = inner.width as usize;
         let mut lines: Vec<Line> = vec![Line::from(Span::styled(
             "sessions",
             Style::default().add_modifier(Modifier::BOLD),
         ))];
         for s in &self.sessions {
-            let glyph = match (s.status, self.attached.contains(&s.id)) {
-                (SessionStatus::Dead, _) => "✗",
-                (SessionStatus::Running, true) => "●",
-                (SessionStatus::Running, false) => "○",
-            };
-            let label = name_for(s);
-            let style = if self.highlight == Some(s.id) {
-                Style::default().add_modifier(Modifier::REVERSED)
-            } else {
-                Style::default()
-            };
-            lines.push(Line::from(vec![
-                Span::raw("  "),
-                Span::styled(format!("{glyph} {label}"), style),
-            ]));
+            let highlighted = self.highlight == Some(s.id);
+            let base = card_base(highlighted);
+            lines.push(Line::from(self.name_row(s, width)));
+            if let Some(meta) = self.meta_row(s, width) {
+                lines.push(Line::from(pad_to_width(meta, width, base)));
+            }
         }
         f.render_widget(Paragraph::new(lines), inner);
     }
+
+    fn name_row(&self, s: &Session, width: usize) -> Vec<Span<'static>> {
+        let glyph = match (s.status, self.attached.contains(&s.id)) {
+            (SessionStatus::Dead, _) => "✗",
+            (SessionStatus::Running, true) => "●",
+            (SessionStatus::Running, false) => "○",
+        };
+        let highlighted = self.highlight == Some(s.id);
+        let base = card_base(highlighted);
+        // Line-1 actions are keyboard affordances shown on the highlighted
+        // row only; they reserve their width so the name truncates with `…`
+        // before it can ever reach them (docs/SIDEBAR.md).
+        let actions_width = if highlighted {
+            ACTIONS.chars().count()
+        } else {
+            0
+        };
+        let usable = width.saturating_sub(actions_width);
+        let prefix = INDENT.chars().count() + 2;
+        // Keep one column of separation between a truncated name and the
+        // actions so the ellipsis never touches them.
+        let sep = if highlighted { 1 } else { 0 };
+        let name_budget = usable.saturating_sub(prefix + sep);
+
+        let mut spans: Vec<Span<'static>> = vec![
+            Span::styled(INDENT, base),
+            Span::styled(format!("{glyph} "), base),
+        ];
+        spans.extend(
+            fit_to_width(vec![Span::raw(name_for(s))], name_budget)
+                .into_iter()
+                .map(|sp| Span::styled(sp.content, base.patch(sp.style))),
+        );
+        let used: usize = spans.iter().map(|sp| sp.width()).sum();
+        if let Some(fill) = usable.checked_sub(used).filter(|&n| n > 0) {
+            spans.push(Span::styled(
+                " ".repeat(fill),
+                Style::default().bg(base.bg.unwrap_or(Color::Reset)),
+            ));
+        }
+        if highlighted {
+            spans.push(Span::styled(ACTIONS, base));
+        }
+        spans
+    }
+
+    /// The adaptive second line: `<dot> <duration> [<blocked work> | exited]`.
+    fn meta_row(&self, s: &Session, width: usize) -> Option<Vec<Span<'static>>> {
+        let now = Utc::now();
+        let held = held_for(s, now);
+        let held_secs = held.map(|d| d.num_seconds()).unwrap_or(0);
+        // #83: a worktree that blocks a kill is summarised here rather than
+        // on line 1; the kill confirm names the specifics.
+        let blocked = s.blocked_work.filter(|b| !b.is_clear());
+        let dead = s.status == SessionStatus::Dead;
+        let errored = s.activity == ActivityState::Error;
+        if (held.is_none() || held_secs < META_LINE_AFTER_SECS)
+            && blocked.is_none()
+            && !dead
+            && !errored
+        {
+            return None;
+        }
+        let base = card_base(self.highlight == Some(s.id));
+        let dot_style = base.patch(Style::default().fg(activity_color(s.activity)));
+        let muted = Style::default().bg(base.bg.unwrap_or(Color::Reset));
+        let mut spans = vec![
+            Span::styled(META_INDENT, base),
+            Span::styled("●", dot_style),
+        ];
+        if let Some(d) = held {
+            spans.push(Span::styled(" ", base));
+            spans.push(Span::styled(format_state_duration(d), dot_style));
+        }
+        if let Some(b) = blocked {
+            spans.push(Span::styled(format!(" ⚠ {b}"), muted));
+        }
+        if dead {
+            spans.push(Span::styled(" exited", muted));
+        }
+        Some(fit_to_width(spans, width))
+    }
+}
+
+/// ratatui colour for an [`ActivityState`], per docs/SIDEBAR.md. The state
+/// word is never spelled out — this colour carries it.
+fn activity_color(state: ActivityState) -> Color {
+    match state {
+        ActivityState::Active => Color::Green,
+        ActivityState::Idle => Color::DarkGray,
+        ActivityState::AwaitingInput => Color::Yellow,
+        ActivityState::Error => Color::Red,
+    }
+}
+
+/// docs/SIDEBAR.md duration format — floored whole seconds / minutes / hours,
+/// measured in the current activity state. No days, no rounding up.
+/// How long the session has held its current activity state, or `None` when
+/// the daemon never reported one (see [`PLAUSIBLE_SINCE_YEAR`]).
+fn held_for(s: &Session, now: chrono::DateTime<Utc>) -> Option<chrono::Duration> {
+    use chrono::Datelike;
+    if s.activity_since.year() < PLAUSIBLE_SINCE_YEAR {
+        return None;
+    }
+    Some(now - s.activity_since)
+}
+
+fn format_state_duration(elapsed: chrono::Duration) -> String {
+    let secs = elapsed.num_seconds().max(0);
+    match secs {
+        0..=59 => format!("{secs}s"),
+        60..=3599 => format!("{}m", secs / 60),
+        _ => format!("{}h", secs / 3600),
+    }
+}
+
+/// Truncate a span list to `max` columns, ending it with `…` when cut. The
+/// sidebar is narrow: card lines truncate, they never wrap.
+fn fit_to_width(spans: Vec<Span<'static>>, max: usize) -> Vec<Span<'static>> {
+    let mut out: Vec<Span<'static>> = Vec::with_capacity(spans.len());
+    let mut used = 0usize;
+    for span in spans {
+        let w = span.width();
+        if used + w <= max {
+            used += w;
+            out.push(span);
+            continue;
+        }
+        let budget = max.saturating_sub(used + 1);
+        let ellipsis = "…";
+        if budget > 0 {
+            let text: String = span.content.chars().take(budget).collect();
+            out.push(Span::styled(format!("{text}{ellipsis}"), span.style));
+        } else if used < max {
+            out.push(Span::styled(ellipsis, span.style));
+        }
+        return out;
+    }
+    out
+}
+
+/// Pad a card row out to the full sidebar width so the card background
+/// paints edge to edge rather than stopping at the last glyph.
+fn pad_to_width(mut spans: Vec<Span<'static>>, width: usize, base: Style) -> Vec<Span<'static>> {
+    let used: usize = spans.iter().map(|sp| sp.width()).sum();
+    if let Some(fill) = width.checked_sub(used).filter(|&n| n > 0) {
+        let pad_style = Style::default().bg(base.bg.unwrap_or(Color::Reset));
+        spans.push(Span::styled(" ".repeat(fill), pad_style));
+    }
+    spans
 }
 
 /// `metadata.name` if present, else the command line.
@@ -78,8 +250,10 @@ fn name_for(s: &Session) -> String {
 #[cfg(test)]
 mod tests {
     use super::*;
-    use chrono::Utc;
+    use chrono::{DateTime, Duration};
+    use maestro_protocol::InTheWay;
     use ratatui::backend::TestBackend;
+    use ratatui::buffer::Buffer;
     use ratatui::Terminal;
     use std::collections::HashMap;
 
@@ -97,24 +271,43 @@ mod tests {
             created_at: Utc::now(),
             foreground: None,
             activity: Default::default(),
-            last_activity_at: chrono::Utc::now(),
+            last_activity_at: Utc::now(),
+            activity_since: Utc::now(),
             current_cwd: None,
+            blocked_work: None,
         }
     }
 
-    fn render_to_string(sidebar: &Sidebar, w: u16, h: u16) -> String {
+    fn draw(sidebar: &Sidebar, w: u16, h: u16) -> Buffer {
         let backend = TestBackend::new(w, h);
         let mut terminal = Terminal::new(backend).unwrap();
         terminal.draw(|f| sidebar.render(f, f.area())).unwrap();
-        let buf = terminal.backend().buffer().clone();
-        let mut out = String::new();
-        for y in 0..buf.area.height {
-            for x in 0..buf.area.width {
-                out.push_str(buf[(x, y)].symbol());
-            }
-            out.push('\n');
-        }
-        out
+        terminal.backend().buffer().clone()
+    }
+
+    fn rows(buf: &Buffer) -> Vec<String> {
+        (0..buf.area.height)
+            .map(|y| {
+                (0..buf.area.width)
+                    .map(|x| buf[(x, y)].symbol())
+                    .collect::<String>()
+            })
+            .collect()
+    }
+
+    fn render_to_string(buf: &Buffer) -> String {
+        rows(buf).join("\n")
+    }
+
+    fn row_containing<'a>(rows: &'a [String], needle: &str) -> &'a str {
+        rows.iter()
+            .find(|l| l.contains(needle))
+            .unwrap_or_else(|| panic!("no row containing {needle:?} in {rows:#?}"))
+    }
+
+    /// Row text without the trailing space padding and right border.
+    fn content(row: &str) -> &str {
+        row.trim_end().trim_end_matches('│').trim_end()
     }
 
     #[test]
@@ -124,7 +317,7 @@ mod tests {
             highlight: None,
             attached: Default::default(),
         };
-        let rendered = render_to_string(&sb, 28, 12);
+        let rendered = render_to_string(&draw(&sb, 28, 12));
         assert!(
             rendered.contains("claude"),
             "missing session name:\n{rendered}"
@@ -143,11 +336,8 @@ mod tests {
             highlight: None,
             attached: [sid].into_iter().collect(),
         };
-        let rendered = render_to_string(&sb, 28, 6);
-        let line = rendered
-            .lines()
-            .find(|l| l.contains("claude"))
-            .expect("claude row");
+        let all = rows(&draw(&sb, 28, 6));
+        let line = row_containing(&all, "claude");
         assert!(line.contains('●'), "expected filled glyph in: {line:?}");
         assert!(
             !line.contains('○'),
@@ -164,14 +354,218 @@ mod tests {
             highlight: None,
             attached: Default::default(),
         };
-        let rendered = render_to_string(&sb, 28, 6);
-        let line = rendered
-            .lines()
-            .find(|l| l.contains("claude"))
-            .expect("claude row");
+        let buf = draw(&sb, 28, 6);
+        let all = rows(&buf);
+        let line = row_containing(&all, "claude");
         assert!(line.contains('✗'), "expected dead glyph in: {line:?}");
     }
 
+    /// #83 via docs/SIDEBAR.md: blocked work lives on the meta line now, not
+    /// on the name row; a clear or unprobed worktree never warns.
+    #[test]
+    fn blocked_session_warns_on_its_meta_line() {
+        let mut blocked = session_named(1, "claude");
+        blocked.activity_since = Utc::now() - Duration::seconds(5);
+        blocked.blocked_work = Some(InTheWay {
+            unpushed_commits: 4,
+            ..InTheWay::default()
+        });
+        let mut clear = session_named(2, "bash");
+        clear.blocked_work = Some(InTheWay::default());
+        let unprobed = session_named(3, "vim");
+        let sb = Sidebar {
+            sessions: vec![blocked, clear, unprobed],
+            highlight: None,
+            attached: Default::default(),
+        };
+        let all = rows(&draw(&sb, 40, 10));
+
+        let meta = all
+            .iter()
+            .find(|l| l.contains("⚠"))
+            .expect("blocked card must warn somewhere");
+        assert!(
+            meta.contains("4 unpushed commits"),
+            "warning must carry InTheWay's summary: {meta:?}"
+        );
+        let name_row = row_containing(&all, "claude");
+        assert!(
+            !name_row.contains('⚠'),
+            "warning moved off the name row: {name_row:?}"
+        );
+        for name in ["bash", "vim"] {
+            let idx = all.iter().position(|l| l.contains(name)).unwrap();
+            assert!(
+                !all[idx + 1].contains('⚠'),
+                "{name} must not warn: {:?}",
+                all[idx + 1]
+            );
+        }
+    }
+
+    /// A freshly-active session stays one line — never an empty placeholder
+    /// row (docs/SIDEBAR.md).
+    #[test]
+    fn freshly_active_session_stays_one_line() {
+        let mut s = session_named(1, "claude");
+        s.activity_since = Utc::now() - Duration::seconds(10);
+        let sb = Sidebar {
+            sessions: vec![s],
+            highlight: None,
+            attached: Default::default(),
+        };
+        let all = rows(&draw(&sb, 28, 8));
+        assert_eq!(content(&all[0]), "sessions");
+        assert!(row_containing(&all, "claude").contains('○'));
+        assert!(
+            content(&all[2]).is_empty(),
+            "line 2 must be absent, got {:?}",
+            all[2]
+        );
+    }
+
+    /// Rule 1 of docs/SIDEBAR.md: held in state longer than 30s earns the
+    /// meta line, with the floored duration next to the dot.
+    #[test]
+    fn long_held_session_gets_a_meta_line_with_duration() {
+        let mut s = session_named(1, "claude");
+        s.activity_since = Utc::now() - Duration::seconds(90);
+        let sb = Sidebar {
+            sessions: vec![s],
+            highlight: None,
+            attached: Default::default(),
+        };
+        let all = rows(&draw(&sb, 28, 8));
+        let idx = all.iter().position(|l| l.contains("claude")).unwrap();
+        let meta = &all[idx + 1];
+        assert!(meta.contains('●'), "meta line carries the dot: {meta:?}");
+        assert!(meta.contains("1m"), "expected 1m in: {meta:?}");
+    }
+
+    #[test]
+    fn duration_format_floors_whole_units() {
+        let fmt = |secs| format_state_duration(Duration::seconds(secs));
+        assert_eq!(fmt(0), "0s");
+        assert_eq!(fmt(45), "45s");
+        assert_eq!(fmt(59), "59s");
+        assert_eq!(fmt(60), "1m");
+        assert_eq!(fmt(240), "4m");
+        assert_eq!(fmt(3599), "59m");
+        assert_eq!(fmt(3600), "1h");
+        assert_eq!(fmt(7200), "2h");
+    }
+
+    /// The dot and duration carry the activity state's colour; the state word
+    /// is never spelled out (docs/SIDEBAR.md colour table).
+    #[test]
+    fn meta_line_dot_uses_the_contract_colour_per_state() {
+        for (state, expected) in [
+            (ActivityState::Active, Color::Green),
+            (ActivityState::Idle, Color::DarkGray),
+            (ActivityState::AwaitingInput, Color::Yellow),
+            (ActivityState::Error, Color::Red),
+        ] {
+            let mut s = session_named(1, "claude");
+            s.activity = state;
+            s.activity_since = Utc::now() - Duration::seconds(120);
+            let sb = Sidebar {
+                sessions: vec![s],
+                highlight: None,
+                attached: Default::default(),
+            };
+            let buf = draw(&sb, 28, 8);
+            let found = (0..buf.area.height)
+                .any(|y| (0..buf.area.width).any(|x| buf[(x, y)].style().fg == Some(expected)));
+            assert!(found, "expected some cell in fg {expected:?} for {state:?}");
+        }
+    }
+
+    /// Rule 3 of docs/SIDEBAR.md: a dead session always gets a meta line,
+    /// even freshly dead, with the muted `exited` fragment.
+    #[test]
+    fn dead_session_shows_exited_on_its_meta_line() {
+        let mut s = session_named(1, "claude");
+        s.status = SessionStatus::Dead;
+        s.activity_since = Utc::now() - Duration::seconds(5);
+        let sb = Sidebar {
+            sessions: vec![s],
+            highlight: None,
+            attached: Default::default(),
+        };
+        let all = rows(&draw(&sb, 28, 8));
+        let idx = all.iter().position(|l| l.contains("claude")).unwrap();
+        assert!(
+            all[idx + 1].contains("exited"),
+            "expected exited fragment in: {:?}",
+            all[idx + 1]
+        );
+    }
+
+    /// The sidebar is narrow: the meta line truncates with `…` and never
+    /// wraps onto a third row (docs/SIDEBAR.md).
+    #[test]
+    fn meta_line_truncates_instead_of_wrapping() {
+        let mut s = session_named(1, "claude");
+        s.activity_since = Utc::now() - Duration::seconds(5);
+        s.blocked_work = Some(InTheWay {
+            uncommitted_files: 120,
+            ..InTheWay::default()
+        });
+        let sb = Sidebar {
+            sessions: vec![s],
+            highlight: None,
+            attached: Default::default(),
+        };
+        let all = rows(&draw(&sb, 28, 8));
+        let idx = all.iter().position(|l| l.contains("claude")).unwrap();
+        let meta = content(&all[idx + 1]);
+        assert!(
+            meta.trim_end().ends_with('…'),
+            "truncated meta line must end with …: {meta:?}"
+        );
+        assert!(
+            content(&all[idx + 2]).trim().is_empty(),
+            "meta line must not wrap: {:?}",
+            all[idx + 2]
+        );
+    }
+
+    /// docs/SIDEBAR.md: a payload predating #102 carries an epoch
+    /// `activity_since` and so contributes no duration — a card must not claim
+    /// the session has been idle since 1970. The dot still renders when some
+    /// other trigger puts line 2 on screen.
+    #[test]
+    fn epoch_activity_since_renders_no_duration() {
+        let mut legacy = session_named(1, "claude");
+        legacy.activity_since = DateTime::from_timestamp(0, 0).unwrap();
+        legacy.status = SessionStatus::Dead;
+        let sb = Sidebar {
+            sessions: vec![legacy],
+            highlight: None,
+            attached: Default::default(),
+        };
+        let rendered = render_to_string(&draw(&sb, 40, 8));
+        assert!(
+            rendered.contains("exited"),
+            "dead session must still show line 2:\n{rendered}"
+        );
+        assert!(
+            !rendered.contains('h') || !rendered.contains("● "),
+            "no duration may follow the dot for an epoch stamp:\n{rendered}"
+        );
+        for line in rendered.lines().filter(|l| l.contains('●')) {
+            assert!(
+                !line
+                    .split('●')
+                    .nth(1)
+                    .unwrap_or("")
+                    .trim_start()
+                    .starts_with(char::is_numeric),
+                "duration rendered from an epoch stamp: {line:?}"
+            );
+        }
+    }
+
     #[test]
     fn falls_back_to_command_when_name_metadata_is_absent() {
         let s = Session {
@@ -185,19 +579,160 @@ mod tests {
             created_at: Utc::now(),
             foreground: None,
             activity: Default::default(),
-            last_activity_at: chrono::Utc::now(),
-
+            last_activity_at: Utc::now(),
+            activity_since: Utc::now(),
             current_cwd: None,
+            blocked_work: None,
         };
         let sb = Sidebar {
             sessions: vec![s],
             highlight: None,
             attached: Default::default(),
         };
-        let rendered = render_to_string(&sb, 28, 6);
+        let rendered = render_to_string(&draw(&sb, 28, 6));
         assert!(
             rendered.contains("vim"),
             "missing fallback command name:\n{rendered}"
         );
     }
+
+    /// Reversed video makes a card unreadable against a background; cards
+    /// use explicit backgrounds instead (docs/SIDEBAR.md, #108).
+    #[test]
+    fn no_cell_is_ever_reversed() {
+        let mut highlighted = session_named(1, "claude");
+        highlighted.activity_since = Utc::now() - Duration::seconds(120);
+        let sb = Sidebar {
+            sessions: vec![highlighted],
+            highlight: Some(Uuid::from_u128(1)),
+            attached: Default::default(),
+        };
+        let buf = draw(&sb, 28, 8);
+        for y in 0..buf.area.height {
+            for x in 0..buf.area.width {
+                assert!(
+                    !buf[(x, y)]
+                        .style()
+                        .add_modifier
+                        .contains(Modifier::REVERSED),
+                    "reversed video at ({x},{y})"
+                );
+            }
+        }
+    }
+
+    /// The highlighted card gets the focus background; every other card gets
+    /// a card background distinct from the panel's default.
+    #[test]
+    fn cards_use_explicit_backgrounds_with_a_distinct_focus_background() {
+        let one = session_named(1, "claude");
+        let two = session_named(2, "bash");
+        let sb = Sidebar {
+            sessions: vec![one, two],
+            highlight: Some(Uuid::from_u128(1)),
+            attached: Default::default(),
+        };
+        let buf = draw(&sb, 28, 8);
+        let all = rows(&buf);
+        let claude_y = all.iter().position(|l| l.contains("claude")).unwrap();
+        let bash_y = all.iter().position(|l| l.contains("bash")).unwrap();
+
+        assert_eq!(
+            buf[(0, claude_y as u16)].style().bg,
+            Some(Color::Cyan),
+            "focused card must sit on the focus background"
+        );
+        assert_eq!(
+            buf[(0, claude_y as u16)].style().fg,
+            Some(Color::Black),
+            "focused card text must stay readable on cyan"
+        );
+        assert_eq!(
+            buf[(0, bash_y as u16)].style().bg,
+            Some(Color::Black),
+            "unfocused cards must still have a card background"
+        );
+        // The panel itself (header row) stays on the terminal default.
+        assert!(
+            matches!(buf[(0, 0)].style().bg, None | Some(Color::Reset)),
+            "panel must keep the terminal default background"
+        );
+    }
+
+    /// The card background paints the full card width, not just the glyphs.
+    #[test]
+    fn card_background_covers_the_full_card_width() {
+        let s = session_named(1, "claude");
+        let sb = Sidebar {
+            sessions: vec![s],
+            highlight: None,
+            attached: Default::default(),
+        };
+        let buf = draw(&sb, 28, 8);
+        let y = buf.content.iter().position(|c| c.symbol() == "c").unwrap() as u16 / buf.area.width;
+        for x in 0..27 {
+            assert_eq!(
+                buf[(x, y)].style().bg,
+                Some(Color::Black),
+                "gap in card background at col {x}"
+            );
+        }
+    }
+
+    /// Line 1's actions live on the highlighted row's top-right corner.
+    #[test]
+    fn highlighted_row_anchors_the_actions_top_right() {
+        let sb = Sidebar {
+            sessions: vec![session_named(1, "claude")],
+            highlight: Some(Uuid::from_u128(1)),
+            attached: Default::default(),
+        };
+        let all = rows(&draw(&sb, 28, 8));
+        let line = content(row_containing(&all, "claude"));
+        assert!(
+            line.ends_with("⧉ ✕"),
+            "actions must sit at the right edge: {line:?}"
+        );
+    }
+
+    #[test]
+    fn unhighlighted_rows_show_no_actions() {
+        let one = session_named(1, "claude");
+        let two = session_named(2, "bash");
+        let sb = Sidebar {
+            sessions: vec![one, two],
+            highlight: Some(Uuid::from_u128(1)),
+            attached: Default::default(),
+        };
+        let all = rows(&draw(&sb, 28, 8));
+        let line = row_containing(&all, "bash");
+        assert!(
+            !line.contains('⧉') && !line.contains('✕'),
+            "actions are highlight-only: {line:?}"
+        );
+    }
+
+    /// The name truncates with `…` before it can ever reach the reserved
+    /// action width (docs/SIDEBAR.md — overlap is a defect).
+    #[test]
+    fn name_truncates_before_reaching_the_actions() {
+        let mut s = session_named(1, "claude");
+        if let Some(serde_json::Value::String(name)) = s.metadata.get_mut("name") {
+            *name = "an-unreasonably-long-session-name".into();
+        }
+        let sb = Sidebar {
+            sessions: vec![s],
+            highlight: Some(Uuid::from_u128(1)),
+            attached: Default::default(),
+        };
+        let all = rows(&draw(&sb, 28, 8));
+        let line = row_containing(&all, "an-unreasonably");
+        let name_end = line.find('…').expect("name must truncate with …");
+        let actions_start = line.find('⧉').expect("actions must still render");
+        assert!(name_end < actions_start, "name overlaps actions: {line:?}");
+        assert!(
+            line.split_at(actions_start).0.ends_with(' '),
+            "no gap before the actions: {line:?}"
+        );
+    }
 }

docs/SIDEBAR.md

@@ -0,0 +1,104 @@
+# SIDEBAR.md — the session card contract
+
+One rule for how a session is rendered as a card in the sidebar, so the web
+sidebar (#107) and the TUI sidebar (#108) describe a session the same way.
+Read this before changing either. Both clients implement exactly what is
+written here; if it needs to change, change it here first.
+
+A card has **line 1** always and **line 2** only when line 2 has something to
+say.
+
+## Line 1 — name + actions
+
+- Left: the session name — `metadata.name` if present, else the command line
+  (same fallback both clients already use).
+- Right: two actions anchored to the top-right corner: **spawn similar**
+  (`⧉`) and **kill** (`✕`). In the TUI these are keyboard affordances shown on
+  the highlighted row; in the web they are buttons. The glyphs are shared so
+  muscle memory transfers.
+- Actions reserve their fixed width; the name truncates with `…` before it can
+  ever reach them. **Overlap between the name and the actions is a defect** —
+  that overlap is what started this milestone.
+
+Line 1 carries no badges. The `⚠ blocked work` badge (#83) and the `exited`
+badge move off this row into line 2.
+
+## Line 2 — meta line (adaptive)
+
+Rendered only when at least one of these holds:
+
+1. The session has been held in its current activity state longer than
+   **30 seconds** (`activity_since` from #102). A freshly-active session
+   stays one line.
+2. Its worktree holds blocked work: `blocked_work` is `Some` and not clear
+   (`InTheWay::is_clear()`), rendered in `formatInTheWay`'s phrasing on web
+   and as `⚠ <summary>` on the TUI.
+3. It has exited: `status == Dead`.
+4. An agent-reported state (#105) of `Error` is in force (see Precedence).
+
+Otherwise line 2 is absent — never an empty placeholder row.
+
+When present, line 2 reads left to right:
+
+```
+<dot> <duration> [<blocked work> | exited] [<command>]
+```
+
+`<dot>` is a single filled glyph (`●` on both clients) carrying the activity
+state's colour, and `<duration>` follows in the same colour. There is no state
+word and no second badge: the dot exists so the state is still legible when a
+row is dimmed or the terminal renders the duration in the default fg. The dot
+and duration are unconditional parts of line 2; the bracketed fragments appear
+only when their trigger holds. A payload that predates #102 (no usable
+`activity_since`) contributes no duration — the dot still renders.
+
+`<command>` is optional and muted: the session's command line, shown only when
+the rendered name came from `metadata.name` and differs from the command (the
+web has always surfaced this; the TUI may omit it).
+
+## Colour per activity state
+
+The state word is never spelled out — the colour carries it.
+
+| Activity state   | Web token | ratatui colour    |
+| ---------------- | --------- | ----------------- |
+| `Active`         | `--live`  | `Color::Green`    |
+| `Idle`           | `--muted` | `Color::DarkGray` |
+| `AwaitingInput`  | `--warn`  | `Color::Yellow`   |
+| `Error`          | `--danger`| `Color::Red`      |
+
+Web tokens resolve per theme automatically (`styles.css` defines dark, light,
+and `prefers-color-scheme` variants for each). The TUI uses the plain ratatui
+named colours above; do not introduce RGB values or a new palette module for
+this.
+
+The duration text inherits its state's colour; the blocked-work, exited and
+command fragments use the muted colour (`--faint` / default style), since the
+⚠ glyph already signals severity.
+
+## Duration format
+
+Time spent in the **current activity state**, sourced from `activity_since`
+(#102) — *not* time since spawn, and *not* time since last PTY output
+(`last_activity_at`). Both clients compute it identically:
+
+- `< 60s` → whole seconds, floored: `30s`
+- `< 60m` → whole minutes, floored: `4m`
+- `≥ 60m` → whole hours, floored: `2h`
+
+No days unit, no seconds inside minutes, no rounding up. Floor everywhere so
+the counter never shows a duration the state hasn't actually reached yet.
+Clock granularity: re-render at least once every 30s while visible so the
+cutover points land within one tick.
+
+## Precedence
+
+An agent-reported `ActivityState` (#105) overrides the daemon's inference for
+the TTL the report carries; when the TTL expires, inference resumes. Clients
+never blend the two: whichever source is in force supplies both the colour and
+the clock for `activity_since`.
+
+If a client receives an `ActivityState` variant it does not know, it must not
+fail rendering: treat it as `Idle` (neutral/dim, line-2 rules apply as usual)
+until the daemon sends a variant it does know. Rust clients deserialize
+activity leniently for the same reason.

docs/WORKTREES.md

@@ -75,11 +75,16 @@ That is only safe because force retains.
 
 `--force` overrides the refusal and nothing else. It ends the session and
 **retains** the worktree, which enters the retained store with reason
-`force-killed`. Force never removes a tree that would have blocked.
+`force-killed`. Force never removes a tree that would have blocked. A tree
+whose guard is clear never needed the override, so a forced kill removes it as
+usual — force changes what happens to blocked work, not ordinary cleanup.
 
-Ending a session and destroying its work are two separate destructive acts. Each
-is chosen on its own, and the second one — reclaim — is chosen while looking at
-exactly what would be lost.
+Ending a session and destroying its work are two separate destructive acts.
+Each is chosen on its own, and the second one — reclaim — is chosen while
+looking at exactly what would be lost.
+
+A forced kill answers with what was retained and why, so a client can say where
+the work went rather than leaving the operator to wonder.
 
 ### Exiting on its own
 
@@ -92,6 +97,17 @@ Nobody is waiting for an answer here, so there is nothing to refuse; the choice
 only between removing and retaining. It uses the same predicate as the kill, from
 the same place, so the two paths cannot drift apart.
 
+The session itself stays in the catalog marked dead until it is dismissed — the
+replay buffer of a crashed agent outlives it — but its worktree is settled at
+once. Once settled, the session drops its worktree reference, so dismissing it
+afterwards neither refuses (there is no guard left to trip) nor records a second
+store entry.
+
+If settling is impossible — the probe fails, or the store cannot take the entry —
+nothing is destroyed. The tree stays on disk *and* stays attached to the dead
+record, where dismissing it later still goes through `--force`'s
+retain-before-teardown path. Losing the store must never mean losing the work.
+
 ## The retained store
 
 A `state_dir`-backed record of worktrees the daemon created that no longer have a

flake.nix

@@ -125,7 +125,7 @@
             pnpmDeps = (pkgs.fetchPnpmDeps.override { pnpm = pkgs.pnpm_10; }) {
               inherit (finalAttrs) pname version src;
               fetcherVersion = 3;
-              hash = "sha256-Lhi41AtCK69SM4+7zih19+Njf7o2hyXrAV0W6VO9YxU=";
+              hash = "sha256-D9JdgI92vzAY8en2zGEEPd4hwOLVi3sr1joT4b17Be4=";
             };
 
             buildPhase = ''

web/src/activity.test.ts

@@ -0,0 +1,101 @@
+import { describe, expect, it } from "vitest";
+
+import {
+  activityColorSlug,
+  activityDurationLabel,
+  activityHeldMs,
+  showsMetaLine,
+} from "./activity.js";
+import type { Session } from "./types.js";
+
+describe("activityHeldMs", () => {
+  it("measures time spent in the current state", () => {
+    const now = Date.now();
+    const since = new Date(now - 90_000).toISOString();
+    expect(activityHeldMs(since, now)).toBe(90_000);
+  });
+
+  it("returns null for payloads that predate #102 (epoch default)", () => {
+    expect(activityHeldMs(undefined, Date.now())).toBeNull();
+    expect(activityHeldMs(new Date(0).toISOString(), Date.now())).toBeNull();
+  });
+
+  it("returns null for unparseable timestamps", () => {
+    expect(activityHeldMs("not-a-time", Date.now())).toBeNull();
+  });
+
+  it("never goes negative", () => {
+    const now = Date.now();
+    expect(activityHeldMs(new Date(now + 5_000).toISOString(), now)).toBe(0);
+  });
+});
+
+describe("activityDurationLabel (#102)", () => {
+  it("floors whole seconds under a minute", () => {
+    expect(activityDurationLabel(30_400)).toBe("30s");
+    expect(activityDurationLabel(59_900)).toBe("59s");
+  });
+
+  it("floors whole minutes under an hour", () => {
+    expect(activityDurationLabel(60_000)).toBe("1m");
+    expect(activityDurationLabel(4 * 60_000 + 59_999)).toBe("4m");
+  });
+
+  it("floors whole hours from an hour up, with no days unit", () => {
+    expect(activityDurationLabel(60 * 60_000)).toBe("1h");
+    expect(activityDurationLabel(2 * 3_600_000 + 59 * 60_000 + 59_999)).toBe("2h");
+    expect(activityDurationLabel(26 * 3_600_000)).toBe("26h");
+  });
+});
+
+describe("activityColorSlug", () => {
+  it("maps each known state to its contract slug", () => {
+    expect(activityColorSlug("Active")).toBe("active");
+    expect(activityColorSlug("Idle")).toBe("idle");
+    expect(activityColorSlug("AwaitingInput")).toBe("awaiting-input");
+    expect(activityColorSlug("Error")).toBe("error");
+  });
+
+  it("treats an unknown variant as idle so rendering never fails", () => {
+    expect(activityColorSlug("Teleported")).toBe("idle");
+  });
+});
+
+function session(overrides: Partial<Session>): Session {
+  return {
+    id: "11111111-2222-3333-4444-555555555555",
+    cwd: "/home/naps/tea/maestro",
+    command: "claude",
+    env: {},
+    metadata: {},
+    status: "Running",
+    created_at: "2026-08-24T10:00:00Z",
+    activity: "Active",
+    ...overrides,
+  };
+}
+
+describe("showsMetaLine", () => {
+  const fresh = new Date(Date.now() - 10_000).toISOString();
+
+  it("stays hidden for a freshly-active session", () => {
+    expect(showsMetaLine(session({ activity_since: fresh }))).toBe(false);
+  });
+
+  it("appears once the state has been held past 30 seconds", () => {
+    const held = new Date(Date.now() - 31_000).toISOString();
+    expect(showsMetaLine(session({ activity_since: held }))).toBe(true);
+  });
+
+  it("appears for blocked work, exited sessions and reported errors", () => {
+    expect(
+      showsMetaLine(session({ activity_since: fresh, blocked_work: { uncommitted_files: 1 } })),
+    ).toBe(true);
+    expect(showsMetaLine(session({ activity_since: fresh, status: "Dead" }))).toBe(true);
+    expect(showsMetaLine(session({ activity_since: fresh, activity: "Error" }))).toBe(true);
+  });
+
+  it("needs no activity timestamp when another trigger holds", () => {
+    expect(showsMetaLine(session({ activity_since: undefined, status: "Dead" }))).toBe(true);
+  });
+});

web/src/activity.ts

@@ -0,0 +1,56 @@
+// docs/SIDEBAR.md: the session card's meta line — activity colour mapping and
+// the shared duration format. Both clients compute it identically; the TUI
+// mirrors this in crates/maestro-tui.
+
+import type { ActivityState, IsoTimestamp, Session } from "./types.js";
+import { sessionBlockers } from "./types.js";
+
+/** A state held shorter than this keeps the card to one line (contract rule 1). */
+const META_LINE_MIN_HOLD_MS = 30_000;
+
+// Payloads predating #102 default `activity_since` to the Unix epoch; anything
+// implausibly old is treated as "never observed" rather than a huge duration.
+const PLAUSIBLE_EPOCH_MS = Date.UTC(2010, 0, 1);
+
+export function activityHeldMs(since: IsoTimestamp | undefined, now: number): number | null {
+  if (!since) return null;
+  const t = Date.parse(since);
+  if (Number.isNaN(t) || t < PLAUSIBLE_EPOCH_MS) return null;
+  return Math.max(0, now - t);
+}
+
+/** `<60s` → whole seconds, `<60m` → whole minutes, else whole hours. Floored
+ *  everywhere so the counter never shows a duration the state hasn't reached. */
+export function activityDurationLabel(heldMs: number): string {
+  const s = Math.floor(heldMs / 1000);
+  if (s < 60) return `${s}s`;
+  const m = Math.floor(s / 60);
+  if (m < 60) return `${m}m`;
+  return `${Math.floor(m / 60)}h`;
+}
+
+/** CSS hook for the state's colour (`styles.css` maps slugs to tokens). An
+ *  unknown variant degrades to idle so rendering never fails (Precedence). */
+export function activityColorSlug(state: ActivityState | string): string {
+  switch (state) {
+    case "Active":
+      return "active";
+    case "AwaitingInput":
+      return "awaiting-input";
+    case "Error":
+      return "error";
+    default:
+      return "idle";
+  }
+}
+
+/** Line 2 renders only when at least one contract trigger holds. */
+export function showsMetaLine(s: Session, now: number = Date.now()): boolean {
+  const held = activityHeldMs(s.activity_since, now);
+  return (
+    (held !== null && held >= META_LINE_MIN_HOLD_MS) ||
+    sessionBlockers(s) !== null ||
+    s.status === "Dead" ||
+    s.activity === "Error"
+  );
+}

web/src/catalog.test.ts

@@ -0,0 +1,225 @@
+// @vitest-environment happy-dom
+import { beforeAll, describe, expect, it } from "vitest";
+
+import { renderSidebar } from "./catalog.js";
+import type { CatalogListener, CatalogStore } from "./events.js";
+import type { InTheWay, Session } from "./types.js";
+
+// happy-dom runs without a backing store; renderSidebar reads the persisted
+// sidebar width on mount.
+beforeAll(() => {
+  Object.defineProperty(window, "localStorage", {
+    value: { getItem: () => null, setItem: () => {} },
+  });
+  // No daemon here; renderSidebar treats a failed info fetch as "absolute
+  // paths are a fine fallback".
+  window.fetch = () => Promise.reject(new Error("offline"));
+});
+
+function session(overrides: Partial<Session>): Session {
+  return {
+    id: "11111111-2222-3333-4444-555555555555",
+    cwd: "/home/naps/tea/maestro",
+    command: "claude",
+    env: {},
+    metadata: {},
+    status: "Running",
+    created_at: "2026-08-24T10:00:00Z",
+    ...overrides,
+  };
+}
+
+function storeWith(sessions: Session[]): CatalogStore {
+  const state = { sessions: new Map(sessions.map((s) => [s.id, s])) };
+  return {
+    snapshot: () => state,
+    // Like the real store, deliver an immediate snapshot so the sidebar
+    // renders its rows during construction.
+    subscribe: (fn: CatalogListener) => {
+      fn(state);
+      return () => {};
+    },
+  } as unknown as CatalogStore;
+}
+
+function rowFor(el: HTMLElement, id: string): HTMLElement | null {
+  return el.querySelector<HTMLElement>(`[data-session-id="${id}"]`);
+}
+
+describe("blocked-work indicator (#83)", () => {
+  it("marks the row of a blocked session with the shared phrasing", () => {
+    const blocked = session({
+      id: "aaaaaaaa-0000-0000-0000-000000000001",
+      blocked_work: { uncommitted_files: 3, unpushed_commits: 2 },
+    });
+    const el = renderSidebar(storeWith([blocked])).el;
+    const badge = rowFor(el, blocked.id)?.querySelector(".leaf-blocked");
+    expect(badge?.textContent).toContain("⚠");
+    expect(badge?.textContent).toContain("3 uncommitted files, 2 unpushed commits");
+  });
+
+  it("does not mark clear or unprobed sessions", () => {
+    const clear = session({
+      id: "aaaaaaaa-0000-0000-0000-000000000002",
+      blocked_work: {} as InTheWay,
+    });
+    const unprobed = session({
+      id: "aaaaaaaa-0000-0000-0000-000000000003",
+    });
+    const el = renderSidebar(storeWith([clear, unprobed])).el;
+    expect(rowFor(el, clear.id)?.querySelector(".leaf-blocked")).toBeNull();
+    expect(rowFor(el, unprobed.id)?.querySelector(".leaf-blocked")).toBeNull();
+  });
+
+  it("restates the warning at the kill confirm", async () => {
+    const confirmations: string[] = [];
+    window.confirm = (msg?: string) => {
+      confirmations.push(msg ?? "");
+      return false;
+    };
+    const blocked = session({
+      id: "aaaaaaaa-0000-0000-0000-000000000004",
+      command: "bash",
+      blocked_work: { untracked_files: 1 },
+    });
+    const el = renderSidebar(storeWith([blocked])).el;
+    const kill = rowFor(el, blocked.id)?.querySelector<HTMLButtonElement>(".leaf-kill");
+    kill?.click();
+    await Promise.resolve();
+    expect(confirmations).toHaveLength(1);
+    expect(confirmations[0]).toContain("1 untracked file");
+    expect(confirmations[0]).toContain("refused unless forced");
+  });
+
+  it("confirms plainly when nothing blocks", async () => {
+    const confirmations: string[] = [];
+    window.confirm = (msg?: string) => {
+      confirmations.push(msg ?? "");
+      return false;
+    };
+    const plain = session({ id: "aaaaaaaa-0000-0000-0000-000000000005" });
+    const el = renderSidebar(storeWith([plain])).el;
+    rowFor(el, plain.id)?.querySelector<HTMLButtonElement>(".leaf-kill")?.click();
+    await Promise.resolve();
+    expect(confirmations).toEqual(['Kill session "claude"?']);
+  });
+});
+
+describe("session cards (#107)", () => {
+  const ago = (ms: number): string => new Date(Date.now() - ms).toISOString();
+
+  it("keeps the name and the actions in the same flow line, actions reserving their width", () => {
+    const s = session({ id: "aaaaaaaa-0000-0000-0000-000000000010" });
+    const el = renderSidebar(storeWith([s])).el;
+    const line1 = rowFor(el, s.id)?.querySelector<HTMLElement>(".card-line1");
+    expect(line1).not.toBeNull();
+    // Same flex line ⇒ the name truncates before it can ever reach the buttons.
+    expect(line1?.querySelector(".leaf-name")).not.toBeNull();
+    expect(line1?.querySelector(".leaf-actions")).toBe(line1?.lastElementChild);
+  });
+
+  it("stays a single line while freshly active", () => {
+    const s = session({
+      id: "aaaaaaaa-0000-0000-0000-000000000011",
+      activity: "Active",
+      activity_since: ago(5_000),
+    });
+    const el = renderSidebar(storeWith([s])).el;
+    expect(rowFor(el, s.id)?.querySelector(".card-line2")).toBeNull();
+  });
+
+  it("shows dot + floored duration once the state has been held past 30s", () => {
+    const s = session({
+      id: "aaaaaaaa-0000-0000-0000-000000000012",
+      activity: "Active",
+      activity_since: ago(4 * 60_000 + 30_000),
+    });
+    const el = renderSidebar(storeWith([s])).el;
+    const line2 = rowFor(el, s.id)?.querySelector<HTMLElement>(".card-line2");
+    expect(line2?.dataset.activity).toBe("active");
+    expect(line2?.querySelector(".activity-dot")).not.toBeNull();
+    expect(line2?.querySelector(".activity-duration")?.textContent).toBe("4m");
+  });
+
+  it("maps each activity state to its contract slug", () => {
+    const mk = (id: string, activity: string) =>
+      session({
+        id,
+        activity: activity as Session["activity"],
+        status: "Running",
+        activity_since: ago(90_000),
+      });
+    const idle = mk("aaaaaaaa-0000-0000-0000-000000000013", "Idle");
+    const wait = mk("aaaaaaaa-0000-0000-0000-000000000014", "AwaitingInput");
+    const error = mk("aaaaaaaa-0000-0000-0000-000000000015", "Error");
+    const el = renderSidebar(storeWith([idle, wait, error])).el;
+    expect(rowFor(el, idle.id)?.querySelector(".card-line2")?.getAttribute("data-activity")).toBe(
+      "idle",
+    );
+    expect(rowFor(el, wait.id)?.querySelector(".card-line2")?.getAttribute("data-activity")).toBe(
+      "awaiting-input",
+    );
+    expect(rowFor(el, error.id)?.querySelector(".card-line2")?.getAttribute("data-activity")).toBe(
+      "error",
+    );
+  });
+
+  it("treats an unknown activity variant as idle instead of failing to render", () => {
+    const s = session({
+      id: "aaaaaaaa-0000-0000-0000-000000000016",
+      activity: "Teleported" as Session["activity"],
+      activity_since: ago(120_000),
+    });
+    const el = renderSidebar(storeWith([s])).el;
+    const line2 = rowFor(el, s.id)?.querySelector(".card-line2");
+    expect(line2?.getAttribute("data-activity")).toBe("idle");
+    expect(line2?.querySelector(".activity-duration")?.textContent).toBe("2m");
+  });
+
+  it("moves blocked work onto line 2 in the shared phrasing", () => {
+    const s = session({
+      id: "aaaaaaaa-0000-0000-0000-000000000017",
+      blocked_work: { uncommitted_files: 3, unpushed_commits: 2 },
+    });
+    const el = renderSidebar(storeWith([s])).el;
+    const line2 = rowFor(el, s.id)?.querySelector<HTMLElement>(".card-line2");
+    expect(line2?.textContent).toContain("⚠");
+    expect(line2?.textContent).toContain("3 uncommitted files, 2 unpushed commits");
+    // Line 1 carries no badges.
+    expect(rowFor(el, s.id)?.querySelector(".leaf-badge")).toBeNull();
+  });
+
+  it("shows exited on line 2 for dead sessions", () => {
+    const s = session({
+      id: "aaaaaaaa-0000-0000-0000-000000000018",
+      status: "Dead",
+    });
+    const el = renderSidebar(storeWith([s])).el;
+    const line2 = rowFor(el, s.id)?.querySelector<HTMLElement>(".card-line2");
+    expect(line2?.textContent).toContain("exited");
+  });
+
+  it("carries the state word only in tooltips and aria labels, never as text", () => {
+    const s = session({
+      id: "aaaaaaaa-0000-0000-0000-000000000019",
+      command: "claude",
+      metadata: { name: "worker" },
+      activity: "AwaitingInput",
+      activity_since: ago(90_000),
+    });
+    const el = renderSidebar(storeWith([s])).el;
+    const row = rowFor(el, s.id) as HTMLElement;
+    const dot = row.querySelector<HTMLElement>(".activity-dot");
+    expect(dot?.getAttribute("title")).toContain("Awaiting input");
+    expect(dot?.getAttribute("aria-label")).toContain("Awaiting input");
+    expect(row.textContent).not.toMatch(/awaiting.?input/i);
+  });
+
+  it("keeps the attach navigation and depth indentation", () => {
+    const s = session({ id: "aaaaaaaa-0000-0000-0000-00000000001a" });
+    const el = renderSidebar(storeWith([s])).el;
+    const row = rowFor(el, s.id) as HTMLAnchorElement;
+    expect(row.getAttribute("href")).toBe("#/attach/aaaaaaaa-0000-0000-0000-00000000001a");
+    expect(row.style.paddingLeft).toMatch(/^\d+(\.\d+)?px$/);
+  });
+});

web/src/catalog.ts

@@ -3,7 +3,8 @@ import { getDaemonInfo, killSession } from "./api.js";
 import { HUD_TOGGLE_EVENT, isHudEnabled, toggleHud } from "./debug.js";
 import { CatalogStore } from "./events.js";
 import type { Session } from "./types.js";
-import { abbreviateFolderName, sessionName } from "./types.js";
+import { abbreviateFolderName, formatInTheWay, sessionBlockers, sessionName } from "./types.js";
+import { activityColorSlug, activityDurationLabel, activityHeldMs, showsMetaLine } from "./activity.js";
 import type { TreeNode } from "./tree.js";
 import { buildTree } from "./tree.js";
 import { createThemeToggle } from "./theme.js";
@@ -17,6 +18,41 @@ export function requestOpenSpawn(): void {
 
 const collapsed = new Set<string>();
 
+// docs/SIDEBAR.md: the state word is never rendered — the dot's colour carries
+// it. It survives only in tooltips/aria labels so meaning is not colour-only.
+const STATE_WORDS: Record<string, string> = {
+  active: "Active",
+  idle: "Idle",
+  "awaiting-input": "Awaiting input",
+  error: "Error",
+};
+
+function metaLine(s: Session, now: number): string {
+  const name = sessionName(s);
+  const dead = s.status === "Dead";
+  const blockers = sessionBlockers(s);
+  const slug = activityColorSlug(s.activity ?? "Idle");
+  const stateWord = STATE_WORDS[slug] ?? STATE_WORDS.idle;
+  const held = activityHeldMs(s.activity_since, now);
+  const duration = held !== null ? activityDurationLabel(held) : null;
+  // The directory is the enclosing folder, so only surface the command — and
+  // only when it isn't already what the name shows.
+  const showCmd = s.command !== name;
+
+  const fragments = [
+    `<span class="activity-dot" role="img" title="${escapeHtml(stateWord)}" aria-label="${escapeHtml(stateWord)}"></span>`,
+    duration ? `<span class="activity-duration">${duration}</span>` : "",
+    blockers
+      ? `<span class="card-flag leaf-blocked" title="Kill will be refused unless forced">⚠ ${escapeHtml(formatInTheWay(blockers))}</span>`
+      : "",
+    dead ? `<span class="card-flag">exited</span>` : "",
+    showCmd
+      ? `<span class="card-flag leaf-cmd" title="${escapeHtml(s.command)}">${escapeHtml(s.command)}</span>`
+      : "",
+  ];
+  return `<span class="card-line2" data-activity="${slug}">${fragments.join("")}</span>`;
+}
+
 function renderNode(node: TreeNode, depth: number): HTMLElement {
   if (node.kind === "folder") {
     const wrap = document.createElement("div");
@@ -52,26 +88,34 @@ function renderNode(node: TreeNode, depth: number): HTMLElement {
   }
 
   const s = node.session;
+  const now = Date.now();
   const row = document.createElement("a");
-  row.className = "tree-leaf";
+  row.className = "tree-leaf session-card";
   row.href = `#/attach/${encodeURIComponent(s.id)}`;
   row.style.paddingLeft = `${depth * 16 + 8}px`;
   row.dataset.sessionId = s.id;
   const running = s.status === "Running";
   row.dataset.status = running ? "running" : "dead";
   const name = sessionName(s);
-  row.setAttribute("aria-label", `${name}, ${running ? "running" : "exited"}`);
-  // The directory is the enclosing folder, so only surface the command — and
-  // only when it isn't already what the name shows.
-  const showCmd = s.command !== name;
+  const stateWord =
+    STATE_WORDS[activityColorSlug(s.activity ?? "Idle")] ?? STATE_WORDS.idle;
+  row.setAttribute(
+    "aria-label",
+    `${name}, ${running ? "running" : "exited"}, ${stateWord}`,
+  );
+  // docs/SIDEBAR.md line 1: name + top-right actions in the same flow line —
+  // the actions reserve their width, so the name truncates before it can ever
+  // reach them. Line 2 renders only when a contract trigger holds.
+  const showMeta = showsMetaLine(s, now);
   row.innerHTML = `
-    <span class="leaf-name">${escapeHtml(name)}</span>
-    ${showCmd ? `<span class="leaf-meta"><span class="leaf-cmd">${escapeHtml(s.command)}</span></span>` : ""}
-    ${running ? "" : `<span class="leaf-badge">exited</span>`}
-    <span class="leaf-actions">
-      <button class="leaf-act leaf-clone" type="button" title="Spawn similar" aria-label="Spawn similar to ${escapeHtml(name)}">⧉</button>
-      <button class="leaf-act leaf-kill" type="button" title="Kill session" aria-label="Kill ${escapeHtml(name)}">✕</button>
+    <span class="card-line1">
+      <span class="leaf-name">${escapeHtml(name)}</span>
+      <span class="leaf-actions">
+        <button class="leaf-act leaf-clone" type="button" title="Spawn similar" aria-label="Spawn similar to ${escapeHtml(name)}">⧉</button>
+        <button class="leaf-act leaf-kill" type="button" title="Kill session" aria-label="Kill ${escapeHtml(name)}">✕</button>
+      </span>
     </span>
+    ${showMeta ? metaLine(s, now) : ""}
   `;
   const similarBtn = row.querySelector(".leaf-clone") as HTMLButtonElement;
   similarBtn.addEventListener("click", (ev) => {
@@ -83,7 +127,12 @@ function renderNode(node: TreeNode, depth: number): HTMLElement {
   killBtn.addEventListener("click", async (ev) => {
     ev.preventDefault();
     ev.stopPropagation();
-    if (!confirm(`Kill session "${sessionName(s)}"?`)) return;
+    // #83: the confirm restates the warning at the moment of decision.
+    const blockers = sessionBlockers(s);
+    const question = blockers
+      ? `Kill session "${name}"? Its worktree still has ${formatInTheWay(blockers)} — the kill will be refused unless forced.`
+      : `Kill session "${name}"?`;
+    if (!confirm(question)) return;
     try {
       await killSession(s.id);
     } catch (e) {
@@ -386,6 +435,13 @@ export function renderSidebar(store: CatalogStore, opts: SidebarOptions = {}): S
 
   const unsubscribe = store.subscribe(refresh);
 
+  // Contract granularity: re-render at least every 30s while visible so the
+  // duration cutover points land within one tick.
+  const clock = setInterval(() => {
+    if (document.visibilityState !== "visible") return;
+    refresh();
+  }, 30_000);
+
   return {
     el,
     setActive(id: string | null) {
@@ -401,6 +457,7 @@ export function renderSidebar(store: CatalogStore, opts: SidebarOptions = {}): S
       applyHighlights();
     },
     dispose() {
+      clearInterval(clock);
       document.removeEventListener("catalog-rerender", rerenderHandler);
       unsubscribe();
     },

web/src/fastForward.test.ts

@@ -43,7 +43,6 @@ describe("resolveFastForward (#67)", () => {
     expect(req.worktree).toEqual({
       base_repo: "/repos/fresh",
       branch: "amber-falcon",
-      cleanup_on_kill: true,
       create_branch: true,
     });
   });

web/src/fastForward.ts

@@ -42,7 +42,6 @@ export function buildFastForwardRequest(
     worktree: {
       base_repo: project.base_repo ?? project.path,
       branch: name,
-      cleanup_on_kill: true,
       create_branch: true,
     },
   };

web/src/kit.ts

@@ -59,20 +59,28 @@ function leafRow(opts: {
   status: "running" | "dead";
   active?: boolean;
   indent?: number;
+  activity?: "active" | "idle" | "awaiting-input" | "error";
+  duration?: string;
 }): HTMLElement {
-  const row = h("a", "tree-leaf");
+  const row = h("a", "tree-leaf session-card");
   (row as HTMLAnchorElement).href = "#/kit";
   row.dataset.status = opts.status;
   if (opts.active) row.classList.add("is-active");
   row.style.paddingLeft = `${(opts.indent ?? 0) * 16 + 8}px`;
+  const flags = [
+    opts.status === "dead" ? `<span class="card-flag">exited</span>` : "",
+    opts.cmd !== opts.name ? `<span class="card-flag leaf-cmd">${opts.cmd}</span>` : "",
+  ].join("");
   row.innerHTML = `
-    <span class="leaf-name">${opts.name}</span>
-    ${opts.cmd !== opts.name ? `<span class="leaf-meta"><span class="leaf-cmd">${opts.cmd}</span></span>` : ""}
-    ${opts.status === "dead" ? `<span class="leaf-badge">exited</span>` : ""}
-    <span class="leaf-actions">
-      <button class="leaf-act leaf-clone" type="button" title="Spawn similar" aria-label="Spawn similar to ${opts.name}">⧉</button>
-      <button class="leaf-act leaf-kill" type="button" title="Kill session" aria-label="Kill ${opts.name}">✕</button>
-    </span>`;
+    <span class="card-line1">
+      <span class="leaf-name">${opts.name}</span>
+      <span class="leaf-actions">
+        <button class="leaf-act leaf-clone" type="button" title="Spawn similar">⧉</button>
+        <button class="leaf-act leaf-kill" type="button" title="Kill session">✕</button>
+      </span>
+    </span>
+    ${opts.activity ? `<span class="card-line2" data-activity="${opts.activity}"><span class="activity-dot" title="${opts.activity}"></span><span class="activity-duration">${opts.duration ?? ""}</span>${flags}</span>` : ""}
+  `;
   return row;
 }
 
@@ -190,14 +198,17 @@ export function renderKit(): HTMLElement {
   // --- chips & badges ---
   {
     const { el, body } = section("Chips & badges", "Status-bearing pills and counts.");
+    const activeLine = h(
+      "span",
+      "card-line2",
+      `<span class="activity-dot"></span><span class="activity-duration">4m</span>`,
+    );
+    activeLine.setAttribute("data-activity", "active");
     body.append(
       specimen("session-tally", h("span", "session-tally", "6 sessions · 5 live")),
       specimen("folder-count", h("span", "folder-count", "4")),
-      specimen("leaf-badge", h("span", "leaf-badge", "exited")),
-      specimen(
-        "attach-state · open",
-        h("span", "attach-state", "live"),
-      ),
+      specimen("card-line2 · active", activeLine),
+      specimen("attach-state · open", h("span", "attach-state", "live")),
     );
     (body.lastElementChild?.querySelector(".attach-state") as HTMLElement)?.setAttribute(
       "data-state",
@@ -215,19 +226,56 @@ export function renderKit(): HTMLElement {
   {
     const { el, body } = section(
       "Session rows — nested by host, then directory",
-      "The working directory (home collapsed to ~) is the nesting, and single-child chains fold into one node like ~/git/maestro. “Alive” is a faint row wash; exited rows recede with a badge; the open session is highlighted.",
+      "docs/SIDEBAR.md cards: line 1 is name + top-right actions (the name truncates before it can reach them); line 2 only when there's something to say — dot + duration in the state's colour, then blocked-work / exited fragments.",
     );
     const list = h("div", "kit-tree");
     list.append(
       folderHeader("~/git/maestro", 3, 0),
       folderHeader("web", 2, 1),
       leafRow({ name: "redesign", cmd: "claude", status: "running", indent: 2 }),
-      leafRow({ name: "dev-server", cmd: "vite dev", status: "running", indent: 2, active: true }),
+      leafRow({
+        name: "dev-server",
+        cmd: "vite dev",
+        status: "running",
+        indent: 2,
+        active: true,
+        activity: "active",
+        duration: "4m",
+      }),
       folderHeader("crates/daemon", 1, 1),
-      leafRow({ name: "daemon-work", cmd: "claude", status: "running", indent: 2 }),
+      leafRow({
+        name: "daemon-work",
+        cmd: "claude",
+        status: "running",
+        indent: 2,
+        activity: "awaiting-input",
+        duration: "12s",
+      }),
+      leafRow({
+        name: "flaky-agent",
+        cmd: "claude",
+        status: "running",
+        indent: 2,
+        activity: "error",
+        duration: "2h",
+      }),
       folderHeader("~/work/acme", 2, 0),
-      leafRow({ name: "billing-api", cmd: "claude", status: "running", indent: 1 }),
-      leafRow({ name: "scratch", cmd: "bash", status: "dead", indent: 1 }),
+      leafRow({
+        name: "billing-api",
+        cmd: "claude",
+        status: "running",
+        indent: 1,
+        activity: "idle",
+        duration: "26m",
+      }),
+      leafRow({
+        name: "scratch",
+        cmd: "bash",
+        status: "dead",
+        indent: 1,
+        activity: "idle",
+        duration: "5h",
+      }),
       leafRow({ name: "monitor", cmd: "btop", status: "running", indent: 0 }),
     );
     body.classList.add("kit-tree-host");

web/src/main.ts

@@ -272,7 +272,11 @@ function showMultiView(): void {
 // cloned session's dir + command.
 function requestOpenSpawn(): void {
   showMultiView();
-  mv.openDraft();
+  // A new tab, not a split of the pane you were reading (#100). "Spawn
+  // similar" and the fast-forward key below deliberately keep the old
+  // behaviour: both act on the session in front of you, so a split beside it
+  // is the point.
+  mv.openDraft(undefined, { newTab: true });
 }
 document.addEventListener(OPEN_SPAWN_EVENT, () => requestOpenSpawn());
 document.addEventListener("catalog-spawn-similar", (ev) => {

web/src/multiview.test.ts

@@ -147,6 +147,48 @@ describe("multiview openDraft (#62)", () => {
     expect((mv.el.querySelector(".mv-draft input[name=name]") as HTMLInputElement).value).toBe("wip");
   });
 
+  it("reuses an already-synced empty pane instead of splitting (#72)", async () => {
+    const layout = emptyLayout();
+    const tab = layout.tabs[0];
+    const first = splitLeaf(tab, "", "s1", "row", true);
+    const empty = splitLeaf(tab, first, null, "row", true);
+    tab.focusedLeafId = empty;
+    const mv = makeMv(layout);
+    document.body.appendChild(mv.el);
+    mv.render();
+    // Let the mounted form's loadProjects() settle and auto-sync its picked
+    // defaults into leaf.draft before openDraft runs (#72's dead-branch window).
+    await flush();
+    expect(leaves(tab.root).find((l) => l.id === empty)?.draft).not.toBeNull();
+
+    mv.openDraft();
+    await flush();
+
+    expect(leaves(tab.root)).toHaveLength(2);
+    expect(tab.focusedLeafId).toBe(empty);
+  });
+
+  it("keeps a seed after reusing an already-synced empty pane (#72)", async () => {
+    const layout = emptyLayout();
+    const tab = layout.tabs[0];
+    const first = splitLeaf(tab, "", "s1", "row", true);
+    const empty = splitLeaf(tab, first, null, "row", true);
+    tab.focusedLeafId = empty;
+    const mv = makeMv(layout);
+    document.body.appendChild(mv.el);
+    mv.render();
+    await flush();
+
+    mv.openDraft({ cwd: "/home/user/proj", command: "claude" });
+    await flush();
+
+    const leaf = leaves(tab.root).find((l) => l.id === empty)!;
+    expect(leaf.draft?.cwd).toBe("/home/user/proj");
+    expect(leaf.draft?.command).toBe("claude");
+    const cwdRaw = mv.el.querySelector(".mv-draft .cwd-raw") as HTMLInputElement;
+    expect(cwdRaw.value).toBe("/home/user/proj");
+  });
+
   it("seeds a clone's cwd and command into the draft", async () => {
     const layout = emptyLayout();
     const mv = makeMv(layout);
@@ -160,3 +202,134 @@ describe("multiview openDraft (#62)", () => {
     expect(leaf.draft?.command).toBe("claude");
   });
 });
+
+describe("multiview pane-drag swap (#73)", () => {
+  beforeEach(() => {
+    stubFetch();
+    document.body.replaceChildren();
+  });
+
+  afterEach(() => {
+    vi.unstubAllGlobals();
+    vi.restoreAllMocks();
+  });
+
+  /** Drag `sourcePane`'s title onto `targetPane`'s center, as the real pane
+   *  drag handler does — modelled after the pointer sequence in runDrag()/
+   *  updateDock() in multiview.ts, since neither is exposed on MultiView. */
+  async function dragPaneOntoCenter(sourcePane: HTMLElement, targetPane: HTMLElement): Promise<void> {
+    // The real drag-start gate requires the pointerdown target to sit inside
+    // an `.attach-header` (attach.ts's session title bar). Draft panes mount
+    // no such element, so stand one in for the gate check itself.
+    const marker = document.createElement("div");
+    marker.className = "attach-header";
+    sourcePane.appendChild(marker);
+
+    vi.spyOn(targetPane, "getBoundingClientRect").mockReturnValue({
+      left: 100,
+      top: 0,
+      width: 100,
+      height: 100,
+      right: 200,
+      bottom: 100,
+      x: 100,
+      y: 0,
+      toJSON() {},
+    } as DOMRect);
+    (document as unknown as { elementsFromPoint: (x: number, y: number) => Element[] }).elementsFromPoint = () => [
+      targetPane,
+    ];
+
+    marker.dispatchEvent(
+      new PointerEvent("pointerdown", { clientX: 0, clientY: 0, bubbles: true, cancelable: true }),
+    );
+    window.dispatchEvent(
+      new PointerEvent("pointermove", { clientX: 150, clientY: 50, bubbles: true, cancelable: true }),
+    );
+    window.dispatchEvent(new PointerEvent("pointerup", { clientX: 150, clientY: 50, bubbles: true, cancelable: true }));
+    await flush();
+  }
+
+  it("moves each draft's form along with its data when two draft panes are swapped", async () => {
+    const layout = emptyLayout();
+    const tab = layout.tabs[0];
+    const leaf1 = splitLeaf(tab, "", null, "row", true);
+    const leaf2 = splitLeaf(tab, leaf1, null, "row", true);
+    const mv = makeMv(layout);
+    document.body.appendChild(mv.el);
+    mv.render();
+    await flush();
+
+    const paneOf = (leafId: string) => mv.el.querySelector(`[data-leaf-id="${leafId}"]`) as HTMLElement;
+    const nameInputOf = (leafId: string) => paneOf(leafId).querySelector("input[name=name]") as HTMLInputElement;
+
+    nameInputOf(leaf1).value = "west";
+    nameInputOf(leaf1).dispatchEvent(new Event("input"));
+    nameInputOf(leaf2).value = "east";
+    nameInputOf(leaf2).dispatchEvent(new Event("input"));
+    await flush();
+    expect(leaves(tab.root).find((l) => l.id === leaf1)?.draft?.name).toBe("west");
+    expect(leaves(tab.root).find((l) => l.id === leaf2)?.draft?.name).toBe("east");
+
+    await dragPaneOntoCenter(paneOf(leaf1), paneOf(leaf2));
+
+    // The leaf data swaps (already correct pre-fix)...
+    expect(leaves(tab.root).find((l) => l.id === leaf1)?.draft?.name).toBe("east");
+    expect(leaves(tab.root).find((l) => l.id === leaf2)?.draft?.name).toBe("west");
+    // ...and the mounted forms must follow, not stay behind showing the old
+    // pane's values (#73).
+    expect(nameInputOf(leaf1).value).toBe("east");
+    expect(nameInputOf(leaf2).value).toBe("west");
+  });
+});
+
+describe("openDraft newTab (#100)", () => {
+  beforeEach(() => {
+    stubFetch();
+    document.body.replaceChildren();
+  });
+
+  afterEach(() => {
+    vi.unstubAllGlobals();
+  });
+
+  it("opens its own tab instead of splitting the focused session", async () => {
+    const layout = emptyLayout();
+    const tab = layout.tabs[0];
+    const first = splitLeaf(tab, "", "s1", "row", true);
+    tab.focusedLeafId = first;
+    const mv = makeMv(layout);
+    document.body.appendChild(mv.el);
+    mv.render();
+
+    mv.openDraft(undefined, { newTab: true });
+    await flush();
+
+    expect(layout.tabs).toHaveLength(2);
+    // The tab you were reading is untouched: still one pane, still its session.
+    const original = leaves(layout.tabs[0].root);
+    expect(original).toHaveLength(1);
+    expect(original[0].sessionId).toBe("s1");
+    // The draft is alone in the new, now-active tab.
+    const fresh = leaves(layout.tabs[1].root);
+    expect(fresh).toHaveLength(1);
+    expect(fresh[0].sessionId).toBeNull();
+    expect(fresh[0].draft).not.toBeNull();
+    expect(layout.activeTabId).toBe(layout.tabs[1].id);
+  });
+
+  it("still splits when newTab is not asked for", async () => {
+    const layout = emptyLayout();
+    const tab = layout.tabs[0];
+    tab.focusedLeafId = splitLeaf(tab, "", "s1", "row", true);
+    const mv = makeMv(layout);
+    document.body.appendChild(mv.el);
+    mv.render();
+
+    mv.openDraft();
+    await flush();
+
+    expect(layout.tabs).toHaveLength(1);
+    expect(leaves(tab.root)).toHaveLength(2);
+  });
+});

web/src/multiview.ts

@@ -57,7 +57,7 @@ export interface MultiView {
   /** Open a draft pane (issue #62): reuse the focused pane if it is already
    *  empty, otherwise split the focused pane. `seed` pre-fills the form
    *  ("Spawn similar" clones a session's cwd + command). */
-  openDraft: (seed?: Partial<Draft>) => void;
+  openDraft: (seed?: Partial<Draft>, opts?: { newTab?: boolean }) => void;
   /** Start dragging a sidebar session into the canvas (issue #32). The
    *  controller owns drag-vs-tap: a tap lets the row's normal click open it, a
    *  drag shows drop zones to place it. */
@@ -412,9 +412,18 @@ export function createMultiView(opts: MultiViewOptions): MultiView {
     opts.onOpenSessionsChange?.();
   }
 
-  function openDraft(seed?: Partial<Draft>): void {
-    const tab = activeTab(layout);
+  function openDraft(seed?: Partial<Draft>, opts?: { newTab?: boolean }): void {
     const draft = (): Draft => ({ command: "", cwd: "", name: "", ...seed });
+    if (opts?.newTab) {
+      // Spawn opens its own tab rather than halving whatever you were reading
+      // (#100). The empty-pane reuse below still applies within a tab.
+      const fresh = addTab(layout);
+      fresh.focusedLeafId = splitLeaf(fresh, "", null, "row", true);
+      findLeaf(fresh.root!, fresh.focusedLeafId)!.draft = draft();
+      render();
+      return;
+    }
+    const tab = activeTab(layout);
     if (!tab.root || !tab.focusedLeafId || !findLeaf(tab.root, tab.focusedLeafId)) {
       // Empty tab (or stale focus): the draft becomes the first pane.
       tab.focusedLeafId = splitLeaf(tab, "", null, "row", true);
@@ -423,9 +432,15 @@ export function createMultiView(opts: MultiViewOptions): MultiView {
       return;
     }
     const target = findLeaf(tab.root, tab.focusedLeafId)!;
-    if (!target.sessionId && !target.draft) {
-      // An already-empty pane becomes the draft in place.
+    if (!target.sessionId) {
+      // Empty = no session, not `!draft` (#72): the mounted form auto-syncs
+      // picked defaults into `draft` once ready, so that's never reliably null.
       target.draft = draft();
+      const stale = draftForms.get(target.id);
+      if (stale) {
+        stale.destroy();
+        draftForms.delete(target.id);
+      }
     } else {
       // Split a fresh draft beside the focused pane.
       tab.focusedLeafId = splitLeaf(tab, target.id, null, "row", true);
@@ -695,6 +710,16 @@ export function createMultiView(opts: MultiViewOptions): MultiView {
         const dragged = findLeaf(tab.root, self)!;
         [dragged.sessionId, target.sessionId] = [target.sessionId, dragged.sessionId];
         [dragged.draft, target.draft] = [target.draft, dragged.draft];
+        // The leaf data moved but each pane's mounted form is still keyed to
+        // its old leaf (#73) — tear both down like openDraft's reuse case
+        // (#72) so render() remounts fresh forms seeded from the swapped data.
+        for (const id of [dragged.id, target.id]) {
+          const stale = draftForms.get(id);
+          if (stale) {
+            stale.destroy();
+            draftForms.delete(id);
+          }
+        }
         tab.focusedLeafId = target.id;
       } else if (sessionId) {
         const loc = locateSession(layout, sessionId);

web/src/projectPicker.test.ts

@@ -34,13 +34,13 @@ function stubFetch(info: unknown, projects: Project[]): void {
   );
 }
 
-function rowPaths(form: HTMLFormElement): string[] {
-  return [...form.querySelectorAll<HTMLButtonElement>(".project-row:not(.project-other)")].map(
-    (r) => r.dataset.cwd ?? "",
+function boxPaths(form: HTMLFormElement): string[] {
+  return [...form.querySelectorAll<HTMLButtonElement>(".project-box")].map(
+    (b) => b.dataset.cwd ?? "",
   );
 }
 
-describe("spawnForm project picker", () => {
+describe("spawnForm project picker (#95: boxes, full paths, mains only)", () => {
   let handle: SpawnFormHandle | null = null;
 
   beforeEach(() => {
@@ -65,7 +65,7 @@ describe("spawnForm project picker", () => {
     return handle;
   }
 
-  it("renders one row per project, fresh before stale", async () => {
+  it("renders one box per project, fresh before stale", async () => {
     const fresh = project({ name: "fresh", path: "/home/user/fresh", last_activity: NOW });
     const stale = project({
       name: "stale",
@@ -73,40 +73,56 @@ describe("spawnForm project picker", () => {
       last_activity: "2026-01-01T00:00:00Z",
     });
     const form = (await mount([stale, fresh])).el;
-    expect(rowPaths(form)).toEqual(["/home/user/fresh", "/home/user/stale"]);
-    const rows = [...form.querySelectorAll<HTMLButtonElement>(".project-row")];
-    expect(rows[1].classList.contains("is-stale")).toBe(true);
-    expect(rows[0].classList.contains("is-stale")).toBe(false);
+    expect(boxPaths(form)).toEqual(["/home/user/fresh", "/home/user/stale"]);
+    const boxes = [...form.querySelectorAll<HTMLButtonElement>(".project-box")];
+    expect(boxes[1].classList.contains("is-stale")).toBe(true);
+    expect(boxes[0].classList.contains("is-stale")).toBe(false);
   });
 
-  it("nests worktrees under their base repository", async () => {
+  it("shows the name as the primary line and the full path unabbreviated", async () => {
+    const p = project({ name: "nixos-config", path: "/home/user/tea/nixos-config" });
+    const form = (await mount([p])).el;
+    const box = form.querySelector<HTMLButtonElement>(".project-box")!;
+    expect(box.querySelector(".project-name")!.textContent).toBe("nixos-config");
+    // Not `~/t/nixos-config`: the abbreviation hid what distinguishes two
+    // projects sharing a basename (#95).
+    expect(box.querySelector(".project-path")!.textContent).toBe("/home/user/tea/nixos-config");
+  });
+
+  it("lists only main checkouts as boxes — worktrees belong to step two", async () => {
     const main = project({ name: "maestro", path: "/home/user/maestro" });
     const wt = project({
       name: "wt",
-      path: "/elsewhere/wt",
+      path: "/home/user/maestro/worktrees/wt",
       is_worktree: true,
       base_repo: main.path,
     });
     const form = (await mount([wt, main])).el;
-    expect(rowPaths(form)).toEqual(["/home/user/maestro", "/elsewhere/wt"]);
-    const [mainRow, wtRow] = [
-      ...form.querySelectorAll(".project-row:not(.project-other)"),
-    ];
-    expect(wtRow.classList.contains("is-worktree")).toBe(true);
-    expect(mainRow.classList.contains("is-worktree")).toBe(false);
+    expect(boxPaths(form)).toEqual(["/home/user/maestro"]);
+    expect(form.querySelector(".project-box.is-worktree")).toBeNull();
   });
 
-  it("filters rows as the operator types", async () => {
+  it("filters boxes as the operator types, keeping a repo its worktree matched", async () => {
     const a = project({ name: "maestro", path: "/home/user/maestro" });
     const b = project({ name: "tea", path: "/home/user/work/tea" });
-    const form = (await mount([a, b])).el;
+    const wt = project({
+      name: "bulgarians",
+      path: "/home/user/maestro/worktrees/bulgarians",
+      is_worktree: true,
+      base_repo: a.path,
+    });
+    const form = (await mount([a, b, wt])).el;
     const filter = form.querySelector<HTMLInputElement>(".project-filter")!;
     filter.value = "tea";
     filter.dispatchEvent(new Event("input"));
-    expect(rowPaths(form)).toEqual(["/home/user/work/tea"]);
+    expect(boxPaths(form)).toEqual(["/home/user/work/tea"]);
+    // A query that only matches a worktree still surfaces its repository box.
+    filter.value = "bulgarians";
+    filter.dispatchEvent(new Event("input"));
+    expect(boxPaths(form)).toEqual(["/home/user/maestro"]);
     filter.value = "zzz";
     filter.dispatchEvent(new Event("input"));
-    expect(rowPaths(form)).toEqual([]);
+    expect(boxPaths(form)).toEqual([]);
     expect(form.querySelector(".picker-empty")).toBeTruthy();
   });
 
@@ -135,17 +151,17 @@ describe("spawnForm project picker", () => {
     for (let i = 0; i < 20; i++) await Promise.resolve();
     onChange.mockClear();
 
-    const row = form.querySelector<HTMLButtonElement>(".project-row")!;
-    row.click();
+    const box = form.querySelector<HTMLButtonElement>(".project-box")!;
+    box.click();
 
     const values = form.querySelector<HTMLInputElement>("input[name=name]")!.value;
     const last = onChange.mock.lastCall![0];
     expect(last.cwd).toBe("/home/user/maestro");
     expect(last.command).toBe("claude");
     expect(values).toBeTruthy();
-    // The raw input stays hidden — the picked row is the source of truth.
+    // The raw input stays hidden — the picked box is the source of truth.
     expect((form.querySelector(".cwd-raw-wrap") as HTMLElement).hidden).toBe(true);
-    expect(row.classList.contains("is-active")).toBe(true);
+    expect(box.classList.contains("is-active")).toBe(true);
   });
 
   it("keeps an 'Other directory…' escape hatch that reveals the raw input", async () => {

web/src/spawnForm.test.ts

@@ -38,7 +38,6 @@ describe("buildSpawnRequest", () => {
         worktree: {
           base_repo: "/home/user/project",
           branch: "feat/foo",
-          cleanup_on_kill: true,
           create_branch: true,
         },
       },
@@ -63,7 +62,6 @@ describe("buildSpawnRequest", () => {
         worktree: {
           base_repo: "/home/user/project",
           branch: "spawn-v2",
-          cleanup_on_kill: true,
           create_branch: false,
         },
       },

web/src/spawnForm.ts

@@ -9,8 +9,8 @@ import {
 } from "./api.js";
 import { attachDirAutocomplete } from "./dirAutocomplete.js";
 import { filterProjects, groupProjects, isStale, sortProjects } from "./projectList.js";
+import type { ProjectGroup } from "./projectList.js";
 import type { BranchInfo, CreateSessionRequest, Project, Session, SpawnPreset } from "./types.js";
-import { abbreviateCwd, abbreviateFolderName } from "./types.js";
 
 /** Where a worktree's branch comes from: freshly created (default) or picked
  * from the repository's existing branches (#61). */
@@ -75,9 +75,6 @@ export function buildSpawnRequest(
     req.worktree = {
       base_repo: baseRepo,
       branch,
-      // The daemon always cleans up, guarded against unsaved work (#56);
-      // the wire field stays for older daemons.
-      cleanup_on_kill: true,
       // Existing-mode picks must check out as-is; the daemon creates
       // anything else with `worktree add -b` (#56/#61).
       create_branch: mode !== "existing",
@@ -97,6 +94,11 @@ export const FALLBACK_PRESETS: SpawnPreset[] = [
   { id: "custom", label: "Custom…", command: "" },
 ];
 
+/** Quiet period after raw-path typing before `/api/gitroot` fires (#74).
+ * Must stay equal to `GITROOT_PROBE_DEBOUNCE_MS` in
+ * crates/maestro-tui/src/draft.rs so both clients debounce alike. */
+const GITROOT_PROBE_DEBOUNCE_MS = 250;
+
 export interface SpawnFormHandle {
   el: HTMLFormElement;
   /** Remove global listeners (dir autocomplete) — call when unmounting. */
@@ -128,15 +130,20 @@ export function createSpawnForm(opts: SpawnFormOptions): SpawnFormHandle {
              placeholder="bash -l" autocomplete="off" />
     </div>
     <div class="field">
-      <span class="field-label">Working directory</span>
+      <span class="field-label">Project</span>
       <input class="raw-input project-filter" type="text" placeholder="Filter projects…"
              autocomplete="off" />
       <div class="picker projects"></div>
+      <button type="button" class="project-other">Other directory…</button>
       <div class="raw-wrap cwd-raw-wrap" hidden>
         <input class="raw-input cwd-raw" name="cwd_raw" type="text"
                placeholder="/home/user/project" inputmode="text" autocomplete="off" />
       </div>
     </div>
+    <div class="field wt-step" hidden>
+      <span class="field-label">Worktree</span>
+      <div class="picker wt-choices"></div>
+    </div>
     <div class="field">
       <span class="field-label">Name</span>
       <div class="name-row">
@@ -145,33 +152,38 @@ export function createSpawnForm(opts: SpawnFormOptions): SpawnFormHandle {
       </div>
     </div>
     <fieldset class="worktree">
-      <legend>
+      <button type="button" class="tree-folder-header wt-toggle" aria-expanded="false">
+        <span class="chevron">▾</span>
+        <span class="folder-name">Advanced options</span>
+        <span class="wt-summary"></span>
+      </button>
+      <div class="wt-collapsible" hidden>
         <label class="row-inline">
           <input type="checkbox" name="worktree_enabled" />
           Create git worktree
         </label>
-      </legend>
-      <p class="wt-hint" hidden></p>
-      <div class="wt-body" hidden>
-        <p class="wt-repo"></p>
-        <div class="wt-mode" role="radiogroup" aria-label="Branch source">
-          <label class="row-inline">
-            <input type="radio" name="worktree_branch_mode" value="new" />
-            New branch
+        <p class="wt-hint" hidden></p>
+        <div class="wt-body" hidden>
+          <p class="wt-repo"></p>
+          <div class="wt-mode" role="radiogroup" aria-label="Branch source">
+            <label class="row-inline">
+              <input type="radio" name="worktree_branch_mode" value="new" />
+              New branch
+            </label>
+            <label class="row-inline">
+              <input type="radio" name="worktree_branch_mode" value="existing" />
+              Existing branch
+            </label>
+          </div>
+          <label class="wt-new-wrap">
+            New branch name
+            <input name="worktree_branch" type="text" placeholder="feat/foo" autocomplete="off" />
           </label>
-          <label class="row-inline">
-            <input type="radio" name="worktree_branch_mode" value="existing" />
-            Existing branch
+          <label class="wt-exist-wrap" hidden>
+            Pick a branch
+            <select class="branch-select"></select>
           </label>
         </div>
-        <label class="wt-new-wrap">
-          Branch
-          <input name="worktree_branch" type="text" placeholder="feat/foo" autocomplete="off" />
-        </label>
-        <label class="wt-exist-wrap" hidden>
-          Branch
-          <select class="branch-select"></select>
-        </label>
       </div>
     </fieldset>
     <p class="form-error" role="alert" aria-live="polite"></p>
@@ -185,11 +197,17 @@ export function createSpawnForm(opts: SpawnFormOptions): SpawnFormHandle {
   const errEl = form.querySelector(".form-error") as HTMLElement;
   const cmdTiles = form.querySelector(".cmd-tiles") as HTMLElement;
   const cmdRaw = form.querySelector(".cmd-raw") as HTMLInputElement;
-  const recentsEl = form.querySelector(".projects") as HTMLElement;
+  const projectsEl = form.querySelector(".projects") as HTMLElement;
   const filterInput = form.querySelector(".project-filter") as HTMLInputElement;
+  const otherBtn = form.querySelector(".project-other") as HTMLButtonElement;
+  const wtStep = form.querySelector(".wt-step") as HTMLElement;
+  const wtChoices = form.querySelector(".wt-choices") as HTMLElement;
   const cwdRawWrap = form.querySelector(".cwd-raw-wrap") as HTMLElement;
   const cwdRaw = form.querySelector(".cwd-raw") as HTMLInputElement;
   const wtEnabled = form.querySelector("input[name=worktree_enabled]") as HTMLInputElement;
+  const wtToggle = form.querySelector(".wt-toggle") as HTMLButtonElement;
+  const wtCollapsible = form.querySelector(".wt-collapsible") as HTMLElement;
+  const wtSummary = form.querySelector(".wt-summary") as HTMLElement;
   const wtHint = form.querySelector(".wt-hint") as HTMLElement;
   const wtBody = form.querySelector(".wt-body") as HTMLElement;
   const wtRepo = form.querySelector(".wt-repo") as HTMLElement;
@@ -340,6 +358,15 @@ export function createSpawnForm(opts: SpawnFormOptions): SpawnFormHandle {
     emit();
   }
 
+  /** Re-highlight the operator's already-picked tile after `renderCommandTiles`
+   * rebuilds the row from scratch (new tiles carry no `is-active` class) —
+   * without touching `command`, since that was already settled. */
+  function reapplyActiveTile(): void {
+    for (const tile of cmdTiles.querySelectorAll(".tile")) {
+      tile.classList.toggle("is-active", (tile as HTMLElement).dataset.id === selectedPresetId);
+    }
+  }
+
   function renderCommandTiles(): void {
     cmdTiles.replaceChildren();
     for (const p of presets) {
@@ -348,13 +375,23 @@ export function createSpawnForm(opts: SpawnFormOptions): SpawnFormHandle {
       tile.className = "tile";
       tile.dataset.id = p.id;
       tile.innerHTML = `<span class="tile-label">${escapeHtml(p.label)}</span>`;
-      tile.addEventListener("click", () => selectPreset(p.id));
+      tile.addEventListener("click", () => {
+        commandTouched = true;
+        selectPreset(p.id);
+      });
       cmdTiles.appendChild(tile);
     }
   }
 
+  // Set once the operator picks a tile or types a custom command — guards
+  // `applyInitialCommand()` the same way `nameTouched` guards a late name
+  // batch: a late `/api/info` resolution must never overwrite a field the
+  // operator has already touched (#76).
+  let commandTouched = false;
+
   cmdRaw.addEventListener("input", () => {
     if (selectedPresetId === "custom" || presets.find((p) => p.id === selectedPresetId)?.command === "") {
+      commandTouched = true;
       command = cmdRaw.value.trim();
       emit();
     }
@@ -370,7 +407,11 @@ export function createSpawnForm(opts: SpawnFormOptions): SpawnFormHandle {
       if (info.presets?.length) {
         presets = info.presets;
         renderCommandTiles();
-        applyInitialCommand();
+        if (commandTouched) {
+          reapplyActiveTile();
+        } else {
+          applyInitialCommand();
+        }
       }
     })
     .catch(() => {
@@ -397,12 +438,36 @@ export function createSpawnForm(opts: SpawnFormOptions): SpawnFormHandle {
     if (first) selectPreset(first.id, false);
   }
 
-  // ---- working-directory picker ---------------------------------------
+  // ---- working-directory picker (#95) ----------------------------------
+  // Two steps, and the TUI mirror (#96) must match these rules verbatim:
+  //  1. Step one is one box per repository (name, then full path). A worktree
+  //     is a box only when its main checkout is missing from the scan.
+  //  2. The filter keeps a repository when the query matches it or any of its
+  //     worktrees, so a worktree name still finds its box.
+  //  3. Picking a box reveals step two: "+ new", then that repository's
+  //     worktrees newest-first. "Other directory…" clears both steps.
+  //  4. "+ new" is the default selection — except on a box that is itself a
+  //     linked worktree, which defaults to that worktree.
+  //  5. "+ new" means create: cwd is the repository, create-worktree on.
+  //     An existing worktree means run in it: cwd is that worktree,
+  //     create-worktree OFF. The daemon never adopts (docs/WORKTREES.md), so
+  //     these are separate acts — #91's rule, now an explicit choice.
+  //  6. Neither step probes /api/gitroot; the scan already reports repository
+  //     membership. Only the free-text hatch pays for a probe.
+
+  /** "new" (create a worktree) or the path of an existing worktree to run in. */
+  type WorktreeChoice = "new" | string;
+
+  let discovered: Project[] = []; // daemon snapshot, daemon-sorted
+  let groups: ProjectGroup[] = []; // rebuilt on every render
+  let selectedGroup: ProjectGroup | null = null;
+  let worktreeChoice: WorktreeChoice = "new";
+
   function showRawCwd(prefillValue?: string, focus = true): void {
     cwdRawWrap.hidden = false;
     if (prefillValue != null) cwd = prefillValue;
     cwdRaw.value = cwd;
-    markActiveProject(null);
+    clearProjectSelection();
     if (focus) {
       cwdRaw.focus();
       cwdRaw.select();
@@ -416,55 +481,98 @@ export function createSpawnForm(opts: SpawnFormOptions): SpawnFormHandle {
     cwd = cwdRaw.value.trim();
     branchCache = null;
     emit();
-    if (wtEnabled.checked) probeGitRoot();
+    if (wtEnabled.checked) scheduleGitRootProbe();
   });
 
-  function markActiveProject(activeCwd: string | null): void {
-    for (const row of recentsEl.querySelectorAll(".project-row")) {
-      row.classList.toggle(
-        "is-active",
-        (row as HTMLElement).dataset.cwd === activeCwd,
-      );
+  /** Every worktree of a group, including the group's own box when the scan
+   * found no main checkout to nest it under. */
+  function worktreesOf(group: ProjectGroup): Project[] {
+    return [group.main, ...group.worktrees].filter((p) => p.is_worktree);
+  }
+
+  function markActiveBox(): void {
+    const active = selectedGroup?.main.path ?? null;
+    for (const box of projectsEl.querySelectorAll(".project-box")) {
+      box.classList.toggle("is-active", (box as HTMLElement).dataset.cwd === active);
     }
   }
 
-  function selectProject(project: Project): void {
-    cwd = project.path;
+  function markActiveChoice(): void {
+    for (const btn of wtChoices.querySelectorAll(".wt-choice")) {
+      const el = btn as HTMLElement;
+      const value = el.dataset.kind === "new" ? "new" : (el.dataset.cwd ?? "");
+      el.classList.toggle("is-active", value === worktreeChoice);
+    }
+  }
+
+  function clearProjectSelection(): void {
+    selectedGroup = null;
+    worktreeChoice = "new";
+    wtChoices.replaceChildren();
+    wtStep.hidden = true;
+    markActiveBox();
+  }
+
+  function selectProject(group: ProjectGroup): void {
+    selectedGroup = group;
     cwdRawWrap.hidden = true;
-    markActiveProject(project.path);
-    // The scan already knows this directory is inside a repo (#61): the
-    // toggle defaults back on and no /api/gitroot round trip is needed.
-    wtEnabled.checked = true;
-    applyProjectRepo(project.base_repo ?? project.path);
+    renderWorktreeChoices(group);
+    markActiveBox();
+    // Rule 4: a box that is itself a linked worktree defaults to running there.
+    applyWorktreeChoice(group.main.is_worktree ? group.main.path : "new");
+  }
+
+  function applyWorktreeChoice(choice: WorktreeChoice): void {
+    const group = selectedGroup;
+    if (!group) return;
+    const target =
+      choice === "new" ? group.main : worktreesOf(group).find((p) => p.path === choice);
+    if (!target) return;
+    worktreeChoice = choice;
+    cwd = target.path;
+    branchCache = null;
+    markActiveChoice();
+    if (choice === "new") {
+      wtEnabled.checked = true;
+      updateWtSummary();
+      applyProjectRepo(group.main.base_repo ?? group.main.path);
+    } else {
+      wtEnabled.checked = false;
+      updateWtSummary();
+      inferredBaseRepo = null;
+      wtBody.hidden = true;
+      wtHint.hidden = true;
+    }
     emit();
-    // Picking a project pre-selects the command it was last used with.
-    const match = presets.find((p) => p.command === project.last_command && p.command !== "");
+    // The chosen directory pre-selects the command it was last used with.
+    const match = presets.find((p) => p.command === target.last_command && p.command !== "");
     if (match) selectPreset(match.id);
   }
 
-  let discovered: Project[] = []; // daemon snapshot, daemon-sorted
+  /** Groups with at least one member (itself or a worktree) matching `query`. */
+  function visibleGroups(query: string): ProjectGroup[] {
+    return groups.filter((g) => filterProjects([g.main, ...g.worktrees], query).length > 0);
+  }
 
   function renderProjects(): void {
-    recentsEl.replaceChildren();
-    const sorted = sortProjects(filterProjects(discovered, filterInput.value), new Date());
-    for (const group of groupProjects(sorted)) {
-      recentsEl.appendChild(projectRow(group.main));
-      for (const wt of group.worktrees) recentsEl.appendChild(projectRow(wt));
-    }
-    if (discovered.length > 0 && sorted.length === 0) {
+    projectsEl.replaceChildren();
+    groups = groupProjects(sortProjects(discovered, new Date()));
+    const visible = visibleGroups(filterInput.value);
+    for (const group of visible) projectsEl.appendChild(projectBox(group));
+    if (discovered.length > 0 && visible.length === 0) {
       const empty = document.createElement("p");
       empty.className = "picker-empty";
       empty.textContent = "No projects match.";
-      recentsEl.appendChild(empty);
+      projectsEl.appendChild(empty);
     }
-    recentsEl.appendChild(otherDirRow());
-    markActiveProject(cwdRawWrap.hidden ? cwd : null);
+    markActiveBox();
   }
 
   filterInput.addEventListener("input", renderProjects);
+  otherBtn.addEventListener("click", () => showRawCwd(cwd || homeDir));
 
   async function loadProjects(): Promise<void> {
-    recentsEl.replaceChildren(loadingRow());
+    projectsEl.replaceChildren(loadingRow());
     try {
       discovered = await fetchProjects();
     } catch {
@@ -475,12 +583,13 @@ export function createSpawnForm(opts: SpawnFormOptions): SpawnFormHandle {
     if (seedCwd) {
       // A seed sets the directory verbatim, regardless of what the scan found.
       // `cwdRawVisible === false` marks a draft restore whose cwd came from a
-      // picked row: keep the picker and don't steal focus. Otherwise land
+      // picked box: keep the picker and don't steal focus. Otherwise land
       // focused in the raw input (clone / no-match flows).
       if (prefill.cwdRawVisible === false) {
         cwd = seedCwd;
         cwdRaw.value = seedCwd;
-        markActiveProject(cwd);
+        // Restoring must not touch the worktree toggle — the seed carries it.
+        if (!restoreSelection(seedCwd)) clearProjectSelection();
       } else {
         showRawCwd(seedCwd, false);
       }
@@ -497,34 +606,66 @@ export function createSpawnForm(opts: SpawnFormOptions): SpawnFormHandle {
     emit();
   }
 
-  function projectRow(project: Project): HTMLElement {
-    const row = document.createElement("button");
-    row.type = "button";
-    row.className = `project-row${project.is_worktree ? " is-worktree" : ""}${
-      isStale(project, new Date()) ? " is-stale" : ""
-    }`;
-    row.dataset.cwd = project.path;
-    // Abbreviate exactly like the sidebar: home → `~`, then collapse leading
-    // segments to initials (`~/g/n/maestro`). The full path stays in the tooltip
-    // and `dataset.cwd` (what's actually submitted).
-    const display = abbreviateFolderName(abbreviateCwd(project.path, homeDir));
-    row.innerHTML = `
-      <span class="project-info">
-        <span class="project-name">${escapeHtml(project.name)}</span>
-        <span class="recent-dir" title="${escapeHtml(project.path)}">${display}</span>
-      </span>
-      <span class="recent-cmd">${escapeHtml(project.last_command ?? "")}</span>`;
-    row.addEventListener("click", () => selectProject(project));
-    return row;
+  /** Put the two steps back on a restored draft's cwd, without re-running the
+   * side effects of a fresh pick. */
+  function restoreSelection(path: string): boolean {
+    for (const group of groups) {
+      const wt = worktreesOf(group).find((p) => p.path === path);
+      const choice: WorktreeChoice | null =
+        wt ? wt.path : group.main.path === path ? "new" : null;
+      if (choice === null) continue;
+      selectedGroup = group;
+      worktreeChoice = choice;
+      renderWorktreeChoices(group);
+      markActiveChoice();
+      markActiveBox();
+      return true;
+    }
+    return false;
   }
 
-  function otherDirRow(): HTMLElement {
-    const row = document.createElement("button");
-    row.type = "button";
-    row.className = "project-row project-other";
-    row.innerHTML = `<span class="project-info"><span class="recent-dir">Other directory…</span></span>`;
-    row.addEventListener("click", () => showRawCwd(cwd || homeDir));
-    return row;
+  function projectBox(group: ProjectGroup): HTMLElement {
+    const project = group.main;
+    const box = document.createElement("button");
+    box.type = "button";
+    box.className = `project-box${isStale(project, new Date()) ? " is-stale" : ""}`;
+    box.dataset.cwd = project.path;
+    const trees = worktreesOf(group).length;
+    // The full path, not the sidebar's `~/t/n/maestro` abbreviation: it is what
+    // tells two projects sharing a basename apart (#95).
+    const meta = [trees > 0 ? `${trees} worktree${trees === 1 ? "" : "s"}` : "", project.last_command ?? ""]
+      .filter(Boolean)
+      .join(" · ");
+    box.innerHTML = `
+      <span class="project-name">${escapeHtml(project.name)}</span>
+      <span class="project-path">${escapeHtml(project.path)}</span>
+      <span class="project-meta">${escapeHtml(meta)}</span>`;
+    box.addEventListener("click", () => selectProject(group));
+    return box;
+  }
+
+  function renderWorktreeChoices(group: ProjectGroup): void {
+    wtChoices.replaceChildren();
+    wtChoices.appendChild(
+      choiceButton("new", "+ new", `new worktree of ${group.main.name}`),
+    );
+    for (const wt of worktreesOf(group)) {
+      wtChoices.appendChild(choiceButton(wt.path, wt.name, wt.path));
+    }
+    wtStep.hidden = false;
+  }
+
+  function choiceButton(choice: WorktreeChoice, label: string, sub: string): HTMLElement {
+    const btn = document.createElement("button");
+    btn.type = "button";
+    btn.className = `wt-choice${choice === "new" ? " wt-choice-new" : ""}`;
+    btn.dataset.kind = choice === "new" ? "new" : "existing";
+    if (choice !== "new") btn.dataset.cwd = choice;
+    btn.innerHTML = `
+      <span class="wt-choice-name">${escapeHtml(label)}</span>
+      <span class="wt-choice-sub">${escapeHtml(sub)}</span>`;
+    btn.addEventListener("click", () => applyWorktreeChoice(choice));
+    return btn;
   }
 
   function loadingRow(): HTMLElement {
@@ -534,6 +675,18 @@ export function createSpawnForm(opts: SpawnFormOptions): SpawnFormHandle {
     return p;
   }
 
+  // ---- worktree: disclosure (#93), reuses the sidebar's folder-header ---
+  let advancedCollapsed = true;
+  function setAdvancedCollapsed(collapsed: boolean): void {
+    advancedCollapsed = collapsed;
+    wtToggle.setAttribute("aria-expanded", String(!collapsed));
+    wtCollapsible.hidden = collapsed;
+  }
+  function updateWtSummary(): void {
+    wtSummary.textContent = wtEnabled.checked ? "creates a worktree" : "no worktree";
+  }
+  wtToggle.addEventListener("click", () => setAdvancedCollapsed(!advancedCollapsed));
+
   // ---- worktree (branch-only; base_repo inferred via scan or /gitroot) --
   // The project scan already reports repo membership, so a picked project
   // resolves its base repo locally (#61); only the free-text escape hatch
@@ -572,7 +725,20 @@ export function createSpawnForm(opts: SpawnFormOptions): SpawnFormHandle {
       applyProjectRepo(project.base_repo ?? project.path);
       return;
     }
-    void probeGitRoot();
+    scheduleGitRootProbe();
+  }
+
+  // Every keystroke resets this timer, so a burst of typing issues one
+  // request once the operator pauses. `probeToken` inside probeGitRoot still
+  // owns ordering: a scheduled probe that fires after a newer one started
+  // loses the token race and is dropped.
+  let probeTimer: number | undefined;
+  function scheduleGitRootProbe(): void {
+    window.clearTimeout(probeTimer);
+    probeTimer = window.setTimeout(() => {
+      probeTimer = undefined;
+      void probeGitRoot();
+    }, GITROOT_PROBE_DEBOUNCE_MS);
   }
 
   async function probeGitRoot(): Promise<void> {
@@ -601,6 +767,7 @@ export function createSpawnForm(opts: SpawnFormOptions): SpawnFormHandle {
       // Publish the untick too, or the next render seeds the box checked with
       // no inferred repo and submitting fails.
       wtEnabled.checked = false;
+      updateWtSummary();
       emit();
       wtBody.hidden = true;
       wtHint.hidden = false;
@@ -674,6 +841,7 @@ export function createSpawnForm(opts: SpawnFormOptions): SpawnFormHandle {
   branchSelect.addEventListener("change", () => emit());
 
   wtEnabled.addEventListener("change", () => {
+    updateWtSummary();
     emit();
     if (wtEnabled.checked) {
       resolveBaseRepo();
@@ -687,6 +855,7 @@ export function createSpawnForm(opts: SpawnFormOptions): SpawnFormHandle {
   // The toggle defaults ON (#61): the operator almost always wants a
   // worktree, and every non-repo target unticks it via the gitroot probe.
   wtEnabled.checked = prefill.worktreeEnabled ?? true;
+  updateWtSummary();
   if (prefill.worktreeBranch) branchInput.value = prefill.worktreeBranch;
   setBranchMode(branchMode);
 
@@ -697,6 +866,43 @@ export function createSpawnForm(opts: SpawnFormOptions): SpawnFormHandle {
   // ---- live dir autocomplete on the raw cwd input (NAP-329) ------------
   const autocomplete = attachDirAutocomplete(cwdRaw);
 
+  // ---- Enter submits from anywhere (#97) --------------------------------
+  // A project-box/wt-choice that isn't yet the active pick takes the Enter to
+  // choose it instead; the next Enter, now that it's active, submits.
+  // dirAutocomplete's own Enter (accept the highlight) already preventDefaults
+  // when it handles the key, which the `e.defaultPrevented` guard defers to.
+  // The worktree checkbox keeps Enter as a toggle (TUI parity: `WorktreeToggle`
+  // does the same) rather than folding it into the blanket-submit rule below.
+  form.addEventListener("keydown", (e) => {
+    if (e.key !== "Enter" || e.defaultPrevented) return;
+    const target = e.target as HTMLElement;
+
+    if (target === wtEnabled) {
+      e.preventDefault();
+      wtEnabled.checked = !wtEnabled.checked;
+      wtEnabled.dispatchEvent(new Event("change"));
+      return;
+    }
+
+    if (target instanceof HTMLButtonElement) {
+      if (!target.classList.contains("project-box") && !target.classList.contains("wt-choice")) return;
+      e.preventDefault();
+      if (!target.classList.contains("is-active")) {
+        target.click();
+        return;
+      }
+      form.requestSubmit();
+      return;
+    }
+
+    e.preventDefault();
+    if (target === filterInput) {
+      const top = visibleGroups(filterInput.value)[0];
+      if (top && top.main.path !== selectedGroup?.main.path) selectProject(top);
+    }
+    form.requestSubmit();
+  });
+
   // ---- submit ----------------------------------------------------------
   form.addEventListener("submit", async (e) => {
     e.preventDefault();
@@ -733,6 +939,7 @@ export function createSpawnForm(opts: SpawnFormOptions): SpawnFormHandle {
     el: form,
     destroy() {
       destroyed = true;
+      window.clearTimeout(probeTimer);
       autocomplete.destroy();
       form.remove();
     },

web/src/spawnFormEnter.test.ts

@@ -0,0 +1,258 @@
+// @vitest-environment happy-dom
+// Enter submits the draft form from any field, at any point (#97). The two
+// exceptions: a picker button that isn't yet the active choice takes the
+// Enter to *choose* it instead (the next Enter submits), and the project
+// filter must resolve to the highlighted project rather than sending
+// whatever cwd was already set.
+import { afterEach, beforeEach, describe, expect, it, vi } from "vitest";
+
+import { createSpawnForm, type SpawnFormHandle } from "./spawnForm.js";
+import type { Project } from "./types.js";
+
+const MAESTRO: Project = {
+  path: "/home/user/tea/maestro",
+  name: "maestro",
+  is_worktree: false,
+  last_activity: "2026-08-20T10:00:00Z",
+};
+
+const WT_A: Project = {
+  path: "/home/user/tea/maestro/worktrees/bulgarians",
+  name: "bulgarians",
+  is_worktree: true,
+  base_repo: MAESTRO.path,
+  last_activity: "2026-08-22T10:00:00Z",
+};
+
+const OTHER: Project = {
+  path: "/home/user/tea/rev",
+  name: "rev",
+  is_worktree: false,
+  last_activity: "2026-08-19T10:00:00Z",
+};
+
+function stubFetch(projects: Project[]): void {
+  vi.stubGlobal(
+    "fetch",
+    vi.fn(async (input: RequestInfo | URL) => {
+      const url = String(input);
+      const body = url.includes("/api/projects")
+        ? projects
+        : url.includes("/api/names")
+          ? { names: ["amber-fox"] }
+          : url.includes("/api/branches")
+            ? []
+            : url.includes("/api/dirs")
+              ? { path: "/opt", entries: ["nomatch-zzz"], truncated: false }
+              : { hostname: "h", version: "0", home_dir: "/home/user", presets: [] };
+      return new Response(JSON.stringify(body), { status: 200 });
+    }),
+  );
+}
+
+describe("spawnForm Enter-to-submit (#97)", () => {
+  let handle: SpawnFormHandle | null = null;
+
+  beforeEach(() => {
+    vi.useFakeTimers({ now: Date.parse("2026-08-23T12:00:00Z") });
+  });
+
+  afterEach(() => {
+    handle?.destroy();
+    handle = null;
+    vi.unstubAllGlobals();
+    vi.useRealTimers();
+  });
+
+  const drain = async () => {
+    for (let i = 0; i < 40; i++) await Promise.resolve();
+  };
+
+  async function mount(projects: Project[]): Promise<HTMLFormElement> {
+    stubFetch(projects);
+    handle = createSpawnForm({ onSuccess() {} });
+    document.body.appendChild(handle.el);
+    await drain();
+    return handle.el;
+  }
+
+  function submitSpy(): ReturnType<typeof vi.fn> {
+    return vi.fn();
+  }
+
+  function pressEnter(el: HTMLElement): { defaultPrevented: boolean } {
+    const evt = new KeyboardEvent("keydown", { key: "Enter", bubbles: true, cancelable: true });
+    el.dispatchEvent(evt);
+    return { defaultPrevented: evt.defaultPrevented };
+  }
+
+  const box = (form: HTMLFormElement, path: string) =>
+    form.querySelector<HTMLButtonElement>(`.project-box[data-cwd="${path}"]`)!;
+
+  it("toggles the worktree checkbox on Enter instead of submitting (TUI parity)", async () => {
+    const form = await mount([MAESTRO]);
+    box(form, MAESTRO.path).click();
+    await drain();
+    const toggle = form.querySelector<HTMLInputElement>("input[name=worktree_enabled]")!;
+    expect(toggle.checked).toBe(true);
+    const spy = submitSpy();
+    form.addEventListener("submit", spy);
+
+    pressEnter(toggle);
+    expect(toggle.checked).toBe(false);
+    expect(spy).not.toHaveBeenCalled();
+
+    pressEnter(toggle);
+    expect(toggle.checked).toBe(true);
+    expect(spy).not.toHaveBeenCalled();
+  });
+
+  describe("submits immediately from ordinary fields", () => {
+    it("name field", async () => {
+      const form = await mount([MAESTRO]);
+      box(form, MAESTRO.path).click();
+      await drain();
+      const spy = submitSpy();
+      form.addEventListener("submit", spy);
+
+      pressEnter(form.querySelector<HTMLInputElement>("input[name=name]")!);
+
+      expect(spy).toHaveBeenCalledTimes(1);
+    });
+
+    it("worktree branch field", async () => {
+      const form = await mount([MAESTRO]);
+      box(form, MAESTRO.path).click();
+      await drain();
+      const spy = submitSpy();
+      form.addEventListener("submit", spy);
+
+      pressEnter(form.querySelector<HTMLInputElement>("input[name=worktree_branch]")!);
+
+      expect(spy).toHaveBeenCalledTimes(1);
+    });
+
+    it("custom command field", async () => {
+      const form = await mount([MAESTRO]);
+      box(form, MAESTRO.path).click();
+      await drain();
+      form.querySelector<HTMLButtonElement>('.cmd-tiles .tile[data-id="custom"]')!.click();
+      const raw = form.querySelector<HTMLInputElement>(".cmd-raw")!;
+      raw.value = "bash -l";
+      raw.dispatchEvent(new Event("input"));
+      const spy = submitSpy();
+      form.addEventListener("submit", spy);
+
+      pressEnter(raw);
+
+      expect(spy).toHaveBeenCalledTimes(1);
+    });
+
+    it("raw cwd field once the autocomplete dropdown is closed", async () => {
+      const form = await mount([MAESTRO]);
+      form.querySelector<HTMLButtonElement>(".project-other")!.click();
+      const raw = form.querySelector<HTMLInputElement>("input[name=cwd_raw]")!;
+      raw.value = "/opt/xyz-nothing-here";
+      raw.dispatchEvent(new Event("input"));
+      await vi.advanceTimersByTimeAsync(300);
+      const spy = submitSpy();
+      form.addEventListener("submit", spy);
+
+      pressEnter(raw);
+
+      expect(spy).toHaveBeenCalledTimes(1);
+    });
+
+    it("does not submit while the raw cwd autocomplete has a highlighted suggestion", async () => {
+      const form = await mount([MAESTRO]);
+      form.querySelector<HTMLButtonElement>(".project-other")!.click();
+      const raw = form.querySelector<HTMLInputElement>("input[name=cwd_raw]")!;
+      raw.focus();
+      raw.value = "/opt/";
+      raw.dispatchEvent(new Event("input", { bubbles: true }));
+      await vi.advanceTimersByTimeAsync(150);
+      const spy = submitSpy();
+      form.addEventListener("submit", spy);
+
+      const { defaultPrevented } = pressEnter(raw);
+
+      expect(defaultPrevented).toBe(true);
+      expect(spy).not.toHaveBeenCalled();
+      expect(raw.value).toBe("/opt/nomatch-zzz/");
+    });
+  });
+
+  describe("two-step picker: first Enter chooses, second submits", () => {
+    it("project box", async () => {
+      const form = await mount([MAESTRO]);
+      const b = box(form, MAESTRO.path);
+      b.focus();
+      const spy = submitSpy();
+      form.addEventListener("submit", spy);
+
+      const first = pressEnter(b);
+      expect(first.defaultPrevented).toBe(true);
+      expect(b.classList.contains("is-active")).toBe(true);
+      expect(spy).not.toHaveBeenCalled();
+
+      pressEnter(b);
+      expect(spy).toHaveBeenCalledTimes(1);
+    });
+
+    it("worktree choice", async () => {
+      const form = await mount([MAESTRO, WT_A]);
+      box(form, MAESTRO.path).click();
+      await drain();
+      const choice = form.querySelector<HTMLButtonElement>(`.wt-choice[data-cwd="${WT_A.path}"]`)!;
+      expect(choice.classList.contains("is-active")).toBe(false); // "+ new" is the default
+      const spy = submitSpy();
+      form.addEventListener("submit", spy);
+
+      pressEnter(choice);
+      expect(choice.classList.contains("is-active")).toBe(true);
+      expect(spy).not.toHaveBeenCalled();
+
+      pressEnter(choice);
+      expect(spy).toHaveBeenCalledTimes(1);
+    });
+  });
+
+  describe("project filter", () => {
+    it("submits with the highlighted (first matching) project, not the filter text", async () => {
+      const form = await mount([MAESTRO, OTHER]);
+      const filter = form.querySelector<HTMLInputElement>(".project-filter")!;
+      filter.value = "rev";
+      filter.dispatchEvent(new Event("input"));
+      const spy = submitSpy();
+      form.addEventListener("submit", spy);
+
+      pressEnter(filter);
+
+      expect(spy).toHaveBeenCalledTimes(1);
+      expect(box(form, OTHER.path).classList.contains("is-active")).toBe(true);
+    });
+
+    it("does not clobber an already-chosen worktree when the filter still matches it", async () => {
+      const form = await mount([MAESTRO, WT_A]);
+      box(form, MAESTRO.path).click();
+      await drain();
+      form.querySelector<HTMLButtonElement>(`.wt-choice[data-cwd="${WT_A.path}"]`)!.click();
+      await drain();
+
+      const filter = form.querySelector<HTMLInputElement>(".project-filter")!;
+      filter.value = "maestro";
+      filter.dispatchEvent(new Event("input"));
+      const spy = submitSpy();
+      form.addEventListener("submit", spy);
+
+      pressEnter(filter);
+
+      expect(spy).toHaveBeenCalledTimes(1);
+      expect(
+        form.querySelector<HTMLButtonElement>(`.wt-choice[data-cwd="${WT_A.path}"]`)!.classList.contains(
+          "is-active",
+        ),
+      ).toBe(true);
+    });
+  });
+});

web/src/spawnFormPreset.test.ts

@@ -0,0 +1,124 @@
+// @vitest-environment happy-dom
+import { afterEach, describe, expect, it, vi } from "vitest";
+
+import { createSpawnForm, type SpawnFormHandle, type SpawnFormValues } from "./spawnForm.js";
+
+/** Stubs fetch so `/api/info` only resolves once `resolveInfo()` is called —
+ * everything else (names, projects, gitroot) answers immediately with an
+ * empty/default body. Lets a test pick a preset (or type a custom command)
+ * mid-flight, then observe what the late `/api/info` resolution does to it. */
+function stubDeferredInfo(): { resolveInfo: () => void } {
+  let releaseInfo: () => void = () => {};
+  const infoGate = new Promise<void>((resolve) => {
+    releaseInfo = resolve;
+  });
+  vi.stubGlobal(
+    "fetch",
+    vi.fn(async (input: RequestInfo | URL) => {
+      const url = String(input);
+      if (url.includes("/api/info")) {
+        await infoGate;
+        return new Response(
+          JSON.stringify({
+            hostname: "h",
+            version: "0",
+            home_dir: "/home/user",
+            presets: [
+              { id: "claude", label: "Claude", command: "claude" },
+              { id: "fish", label: "Fish", command: "fish" },
+              { id: "custom", label: "Custom…", command: "" },
+            ],
+          }),
+          { status: 200 },
+        );
+      }
+      if (url.includes("/api/names")) {
+        return new Response(JSON.stringify({ names: ["amber-fox"] }), { status: 200 });
+      }
+      return new Response(JSON.stringify([]), { status: 200 });
+    }),
+  );
+  return { resolveInfo: releaseInfo };
+}
+
+describe("spawnForm preset selection vs. late /api/info (#76)", () => {
+  let handle: SpawnFormHandle | null = null;
+
+  afterEach(() => {
+    handle?.destroy();
+    handle = null;
+    vi.unstubAllGlobals();
+  });
+
+  async function drain(): Promise<void> {
+    for (let i = 0; i < 40; i++) await Promise.resolve();
+  }
+
+  it("keeps an operator-picked tile after /api/info resolves late", async () => {
+    const { resolveInfo } = stubDeferredInfo();
+    let values: SpawnFormValues | undefined;
+    handle = createSpawnForm({ onChange: (v) => (values = v), onSuccess() {} });
+    const form = handle.el;
+    document.body.appendChild(form);
+    await drain();
+
+    // Fallback presets are up; the operator picks "zsh" before /api/info lands.
+    const zshTile = [...form.querySelectorAll<HTMLButtonElement>(".tile")].find(
+      (t) => t.dataset.id === "zsh",
+    )!;
+    zshTile.click();
+    expect(zshTile.classList.contains("is-active")).toBe(true);
+
+    // /api/info lands late with a preset list that doesn't even include "zsh".
+    resolveInfo();
+    await drain();
+
+    // The operator's pick must not be discarded back to the new list's first
+    // entry — `onChange` only starts firing once the initial load settles
+    // (`ready`), which happens right here, so this is the first place the
+    // published command is observable.
+    expect(values?.command).toBe("zsh");
+  });
+
+  it("keeps an operator-typed custom command after /api/info resolves late", async () => {
+    const { resolveInfo } = stubDeferredInfo();
+    let values: SpawnFormValues | undefined;
+    handle = createSpawnForm({ onChange: (v) => (values = v), onSuccess() {} });
+    const form = handle.el;
+    document.body.appendChild(form);
+    await drain();
+
+    const customTile = [...form.querySelectorAll<HTMLButtonElement>(".tile")].find(
+      (t) => t.dataset.id === "custom",
+    )!;
+    customTile.click();
+    const cmdRaw = form.querySelector<HTMLInputElement>(".cmd-raw")!;
+    cmdRaw.value = "htop";
+    cmdRaw.dispatchEvent(new Event("input"));
+
+    resolveInfo();
+    await drain();
+
+    expect(values?.command).toBe("htop");
+    expect(cmdRaw.value).toBe("htop");
+  });
+
+  it("still applies the real presets' first entry when the operator never touched the command", async () => {
+    const { resolveInfo } = stubDeferredInfo();
+    let values: SpawnFormValues | undefined;
+    handle = createSpawnForm({ onChange: (v) => (values = v), onSuccess() {} });
+    const form = handle.el;
+    document.body.appendChild(form);
+    await drain();
+
+    resolveInfo();
+    await drain();
+
+    // Untouched: the refined preset list is still free to settle the command.
+    expect(values?.command).toBe("claude");
+    const fishTile = [...form.querySelectorAll<HTMLButtonElement>(".tile")].find(
+      (t) => t.dataset.id === "fish",
+    );
+    expect(fishTile).toBeDefined();
+  });
+});

web/src/spawnFormProbe.test.ts

@@ -0,0 +1,148 @@
+// @vitest-environment happy-dom
+import { afterEach, beforeEach, describe, expect, it, vi } from "vitest";
+
+import { createSpawnForm, type SpawnFormHandle } from "./spawnForm.js";
+
+/** Debounce window under test — must equal GITROOT_PROBE_DEBOUNCE_MS in
+ * spawnForm.ts (#74). */
+const DEBOUNCE_MS = 250;
+
+const PROJECTS = [
+  { path: "/home/user/maestro", name: "maestro", last_activity: "2026-08-20T10:00:00Z" },
+];
+
+/** Stub the fetches the form makes. Gitroot responses for a given path can be
+ * held until `releaseGitRoot(path)` is called, so tests can land answers out
+ * of order. */
+function stubFetch(opts?: { holdGitRootFor?: string[] }): {
+  urls: string[];
+  gitRootCalls: string[];
+  releaseGitRoot: (path: string) => void;
+} {
+  const urls: string[] = [];
+  const gitRootCalls: string[] = [];
+  const releases = new Map<string, () => void>();
+  const held = new Map<string, Promise<void>>();
+  vi.stubGlobal(
+    "fetch",
+    vi.fn(async (input: RequestInfo | URL) => {
+      const url = String(input);
+      urls.push(url);
+      if (url.includes("/api/dirs")) {
+        return new Response(JSON.stringify({ entries: [] }), { status: 200 });
+      }
+      if (url.includes("/api/gitroot")) {
+        const path = new URL(url, "http://localhost").searchParams.get("path") ?? "";
+        gitRootCalls.push(path);
+        if (opts?.holdGitRootFor?.includes(path)) {
+          let release!: () => void;
+          held.set(
+            path,
+            new Promise<void>((r) => {
+              release = r;
+            }),
+          );
+          releases.set(path, release);
+        }
+        await held.get(path);
+        return new Response(JSON.stringify({ root: path }), { status: 200 });
+      }
+      if (url.includes("/api/names")) {
+        return new Response(JSON.stringify({ names: ["amber-fox"] }), { status: 200 });
+      }
+      if (url.includes("/api/projects")) {
+        return new Response(JSON.stringify(PROJECTS), { status: 200 });
+      }
+      return new Response(
+        JSON.stringify({ hostname: "h", version: "0", home_dir: "/home/user", presets: [] }),
+        { status: 200 },
+      );
+    }),
+  );
+  return {
+    urls,
+    gitRootCalls,
+    releaseGitRoot: (path: string) => releases.get(path)?.(),
+  };
+}
+
+describe("spawnForm gitroot probe debounce (#74)", () => {
+  let handle: SpawnFormHandle | null = null;
+
+  beforeEach(() => {
+    vi.useFakeTimers();
+  });
+
+  afterEach(() => {
+    handle?.destroy();
+    handle = null;
+    vi.unstubAllGlobals();
+    vi.useRealTimers();
+  });
+
+  async function mount(opts?: Parameters<typeof stubFetch>[0]) {
+    const stub = stubFetch(opts);
+    handle = createSpawnForm({ onSuccess() {} });
+    document.body.appendChild(handle.el);
+    for (let i = 0; i < 40; i++) await Promise.resolve();
+    return { form: handle.el, stub };
+  }
+
+  const drain = async () => {
+    for (let i = 0; i < 40; i++) await Promise.resolve();
+  };
+
+  function typeRaw(form: HTMLFormElement, value: string): void {
+    const raw = form.querySelector<HTMLInputElement>("input[name=cwd_raw]")!;
+    raw.value = value;
+    raw.dispatchEvent(new Event("input"));
+  }
+
+  it("a keystroke burst fires exactly one probe after the quiet period", async () => {
+    const { form, stub } = await mount();
+
+    form.querySelector<HTMLElement>(".project-other")!.click();
+    // Burst: every keystroke reschedules; nothing may hit /api/gitroot yet.
+    for (let i = 1; i <= "/opt/somewhere".length; i++) {
+      typeRaw(form, "/opt/somewhere".slice(0, i));
+      await drain();
+      expect(stub.gitRootCalls).toEqual([]);
+    }
+
+    await vi.advanceTimersByTimeAsync(DEBOUNCE_MS);
+    await drain();
+
+    expect(stub.gitRootCalls).toEqual(["/opt/somewhere"]);
+    expect(stub.urls.filter((u) => u.includes("/api/gitroot")).length).toBe(1);
+  });
+
+  it("a stale probe answer cannot overwrite a newer input", async () => {
+    const { form, stub } = await mount({ holdGitRootFor: ["/repo/old"] });
+
+    form.querySelector<HTMLElement>(".project-other")!.click();
+
+    // Probe for the old target, held in flight.
+    typeRaw(form, "/repo/old");
+    await vi.advanceTimersByTimeAsync(DEBOUNCE_MS);
+
+    // Newer target supersedes it and answers immediately.
+    typeRaw(form, "/repo/new");
+    await vi.advanceTimersByTimeAsync(DEBOUNCE_MS);
+    await drain();
+
+    expect(stub.gitRootCalls).toEqual(["/repo/old", "/repo/new"]);
+    expect(form.querySelector<HTMLElement>(".wt-repo")!.textContent).toContain("/repo/new");
+    expect(
+      form.querySelector<HTMLInputElement>("input[name=worktree_enabled]")!.checked,
+    ).toBe(true);
+
+    // The late answer to the old target lands last but must lose.
+    stub.releaseGitRoot("/repo/old");
+    await drain();
+
+    expect(form.querySelector<HTMLElement>(".wt-repo")!.textContent).toContain("/repo/new");
+    expect(
+      form.querySelector<HTMLInputElement>("input[name=worktree_enabled]")!.checked,
+    ).toBe(true);
+  });
+});

web/src/spawnFormWorktree.test.ts

@@ -18,6 +18,7 @@ const BRANCHES = [
  * its branch list is still in flight. */
 function stubFetch(opts?: {
   gateBranches?: (release: () => void) => void;
+  projects?: unknown[];
 }): string[] {
   const urls: string[] = [];
   const gated = new Promise<void>((resolve) => {
@@ -37,7 +38,7 @@ function stubFetch(opts?: {
         return new Response(JSON.stringify(BRANCHES), { status: 200 });
       }
       if (url.includes("/api/projects")) {
-        return new Response(JSON.stringify(PROJECTS), { status: 200 });
+        return new Response(JSON.stringify(opts?.projects ?? PROJECTS), { status: 200 });
       }
       return new Response(
         JSON.stringify({ hostname: "h", version: "0", home_dir: "/home/user", presets: [] }),
@@ -79,10 +80,10 @@ describe("spawnForm worktree defaults and branch picker (#61)", () => {
   };
 
   function pickProject(form: HTMLFormElement): void {
-    form.querySelector<HTMLButtonElement>(".project-row.project-other")!.click();
+    form.querySelector<HTMLButtonElement>(".project-other")!.click();
     form
-      .querySelectorAll<HTMLButtonElement>(".project-row")
-      .forEach((row) => row.dataset.cwd === "/home/user/maestro" && row.click());
+      .querySelectorAll<HTMLButtonElement>(".project-box")
+      .forEach((box) => box.dataset.cwd === "/home/user/maestro" && box.click());
   }
 
   it("defaults the worktree toggle on for a picked project with no gitroot probe", async () => {
@@ -100,14 +101,44 @@ describe("spawnForm worktree defaults and branch picker (#61)", () => {
     );
   });
 
+  it("defaults the worktree toggle off for a row that is itself a worktree (#91)", async () => {
+    urls = stubFetch({
+      projects: [
+        {
+          path: "/home/user/wt-91",
+          name: "wt-91",
+          is_worktree: true,
+          base_repo: "/home/user/maestro",
+          last_activity: "2026-08-20T10:00:00Z",
+        },
+      ],
+    });
+    handle = createSpawnForm({ onSuccess() {} });
+    document.body.appendChild(handle.el);
+    for (let i = 0; i < 40; i++) await Promise.resolve();
+
+    handle.el
+      .querySelectorAll<HTMLButtonElement>(".project-box")
+      .forEach((box) => box.dataset.cwd === "/home/user/wt-91" && box.click());
+    await drain();
+
+    expect(handle.el.querySelector<HTMLInputElement>("input[name=worktree_enabled]")!.checked).toBe(
+      false,
+    );
+    expect(urls.some((u) => u.includes("/api/gitroot"))).toBe(false);
+    expect(handle.el.querySelector<HTMLElement>(".wt-body")!.hidden).toBe(true);
+  });
+
   it("still probes the gitroot for a free-text directory", async () => {
     const form = await mount();
 
-    // Escape hatch: switch to a free-text dir; only now does /api/gitroot fire.
-    form.querySelector<HTMLElement>(".project-row.project-other")!.click();
+    // Escape hatch: switch to a free-text dir; only now does /api/gitroot
+    // fire — debounced, so the quiet period must elapse first (#74).
+    form.querySelector<HTMLElement>(".project-other")!.click();
     const raw = form.querySelector<HTMLInputElement>("input[name=cwd_raw]")!;
     raw.value = "/opt/somewhere";
     raw.dispatchEvent(new Event("input"));
+    await vi.advanceTimersByTimeAsync(250);
     await drain();
 
     expect(urls.some((u) => u.includes("/api/gitroot"))).toBe(true);
@@ -149,6 +180,74 @@ describe("spawnForm worktree defaults and branch picker (#61)", () => {
     expect(modes.at(-1)).toBe("existing");
   });
 
+  it("labels the new-branch input and existing-branch picker distinctly (#94)", async () => {
+    const form = await mount();
+    pickProject(form);
+    await drain();
+
+    const newLabel = form.querySelector<HTMLElement>(".wt-new-wrap")!.textContent!.trim();
+    const existLabel = form.querySelector<HTMLElement>(".wt-exist-wrap")!.textContent!.trim();
+
+    expect(newLabel).not.toBe("Branch");
+    expect(existLabel).not.toBe("Branch");
+    expect(newLabel).not.toBe(existLabel);
+    expect(newLabel).toMatch(/name/i);
+    expect(existLabel).toMatch(/pick|choose|select/i);
+  });
+
+  it("collapses the advanced (worktree) section by default (#93)", async () => {
+    const form = await mount();
+    const toggle = form.querySelector<HTMLButtonElement>(".wt-toggle")!;
+    expect(toggle.getAttribute("aria-expanded")).toBe("false");
+    expect(form.querySelector<HTMLElement>(".wt-collapsible")!.hidden).toBe(true);
+  });
+
+  it("states in the collapsed header that a worktree will be created by default (#93)", async () => {
+    const form = await mount();
+    expect(form.querySelector<HTMLElement>(".wt-summary")!.textContent).toMatch(/creates? a worktree/i);
+  });
+
+  it("states in the collapsed header that no worktree will be created for a worktree row (#91, #93)", async () => {
+    urls = stubFetch({
+      projects: [
+        {
+          path: "/home/user/wt-91",
+          name: "wt-91",
+          is_worktree: true,
+          base_repo: "/home/user/maestro",
+          last_activity: "2026-08-20T10:00:00Z",
+        },
+      ],
+    });
+    handle = createSpawnForm({ onSuccess() {} });
+    document.body.appendChild(handle.el);
+    for (let i = 0; i < 40; i++) await Promise.resolve();
+
+    handle.el
+      .querySelectorAll<HTMLButtonElement>(".project-box")
+      .forEach((box) => box.dataset.cwd === "/home/user/wt-91" && box.click());
+    await drain();
+
+    expect(handle.el.querySelector<HTMLElement>(".wt-summary")!.textContent).toMatch(/no worktree/i);
+    // Still collapsed — picking a project must not force it open.
+    expect(handle.el.querySelector<HTMLButtonElement>(".wt-toggle")!.getAttribute("aria-expanded")).toBe(
+      "false",
+    );
+  });
+
+  it("expanding the advanced section does not reorder the fields above it (#93)", async () => {
+    const form = await mount();
+    const before = [...form.querySelectorAll(".field")];
+
+    form.querySelector<HTMLButtonElement>(".wt-toggle")!.click();
+
+    expect(form.querySelector<HTMLButtonElement>(".wt-toggle")!.getAttribute("aria-expanded")).toBe(
+      "true",
+    );
+    expect(form.querySelector<HTMLElement>(".wt-collapsible")!.hidden).toBe(false);
+    expect([...form.querySelectorAll(".field")]).toStrictEqual(before);
+  });
+
   it("does not repopulate a destroyed form when the branch list lands late", async () => {
     const gate: { release?: () => void } = {};
     urls = stubFetch({ gateBranches: (r) => (gate.release = r) });

web/src/styles.css

@@ -727,10 +727,8 @@ textarea {
 }
 
 /* Earlier path segments collapse to their initial; the trailing segment (the
-   one that actually names the dir) stays full. Dim the collapsed prefix. Shared
-   by the sidebar tree and the spawn dialog's recent-directory picker. */
-.folder-name .folder-stem,
-.recent-dir .folder-stem {
+   one that actually names the dir) stays full. Dim the collapsed prefix. */
+.folder-name .folder-stem {
   color: var(--faint);
 }
 
@@ -789,53 +787,85 @@ textarea {
   font-weight: 400;
 }
 
+/* #107: session cards per docs/SIDEBAR.md — line 1 (name + top-right actions)
+   always, line 2 (meta) only when it has something to say. */
+.tree-leaf.session-card {
+  flex-direction: column;
+  align-items: stretch;
+  gap: 1px;
+}
+
+.card-line1 {
+  display: flex;
+  align-items: center;
+  gap: var(--sp-2);
+  min-width: 0;
+}
+
 .leaf-name {
   font-weight: 500;
   font-size: var(--fs-13);
-  flex: 0 1 auto;
-  overflow: hidden;
-  text-overflow: ellipsis;
-  white-space: nowrap;
-}
-
-.leaf-meta {
-  font-size: var(--fs-11);
-  color: var(--muted);
-  margin-left: auto;
-  padding-left: var(--sp-2);
+  /* Grows to push the actions to the right edge but shrinks first, so the name
+     truncates before it can ever reach them — overlap is a defect (#107). */
+  flex: 1 1 auto;
   min-width: 0;
-  flex: 0 1 auto;
   overflow: hidden;
   text-overflow: ellipsis;
   white-space: nowrap;
-  display: inline-flex;
-  align-items: baseline;
+}
+
+/* Line 2 — dot + duration in the state's colour, then muted fragments. The
+   state word itself is never spelled out here; the colour carries it. */
+.card-line2 {
+  display: flex;
+  align-items: center;
   gap: var(--sp-2);
-}
-
-.leaf-cmd {
-  color: var(--muted);
-  overflow: hidden;
-  text-overflow: ellipsis;
-  white-space: nowrap;
-}
-
-.leaf-badge {
   font-size: var(--fs-11);
-  letter-spacing: 0.02em;
-  text-transform: uppercase;
+  min-width: 0;
   color: var(--muted);
-  border: 1px solid var(--border);
-  border-radius: var(--r-pill);
-  padding: 1px 8px;
+}
+
+.card-line2[data-activity="active"] {
+  color: var(--live);
+}
+.card-line2[data-activity="idle"] {
+  color: var(--muted);
+}
+.card-line2[data-activity="awaiting-input"] {
+  color: var(--warn);
+}
+.card-line2[data-activity="error"] {
+  color: var(--danger);
+}
+
+.activity-dot {
+  width: 7px;
+  height: 7px;
+  border-radius: 50%;
+  background: currentColor;
   flex: 0 0 auto;
 }
 
+.activity-duration {
+  color: inherit;
+  flex: 0 0 auto;
+}
+
+/* Blocked-work / exited / command fragments recede: the ⚠ glyph already
+   signals severity and "exited" dims with the row. */
+.card-flag {
+  color: var(--faint);
+  min-width: 0;
+  overflow: hidden;
+  text-overflow: ellipsis;
+  white-space: nowrap;
+}
+
+/* Actions live in line 1's flow at its right edge — never overlaid on the
+   name (#107). They reserve their width even while hover-faded. */
 .leaf-actions {
-  position: absolute;
-  right: var(--sp-1);
-  top: 50%;
-  transform: translateY(-50%);
+  flex: 0 0 auto;
+  margin-left: auto;
   display: inline-flex;
   gap: 2px;
 }
@@ -1208,6 +1238,9 @@ textarea {
 /* ---------- forms ---------- */
 
 .spawn-form {
+  width: 100%;
+  max-width: 60ch;
+  margin: 0 auto;
   padding: var(--sp-3);
   overflow: auto;
   display: flex;
@@ -1276,18 +1309,33 @@ textarea {
 .worktree {
   border: 1px solid var(--border);
   border-radius: var(--r-2);
-  padding: var(--sp-3);
+  padding: 0 var(--sp-3);
   margin: 0;
   display: flex;
   flex-direction: column;
-  gap: var(--sp-3);
   background: color-mix(in oklab, var(--surface-2) 50%, transparent);
 }
 
-.worktree legend {
-  padding: 0 6px;
-  color: var(--ink);
-  font-size: var(--fs-13);
+.worktree .wt-toggle {
+  margin: 0 calc(var(--sp-3) * -1);
+  padding-left: var(--sp-3);
+  width: calc(100% + var(--sp-3) * 2);
+}
+
+.wt-summary {
+  color: var(--muted);
+  font-size: var(--fs-12);
+}
+
+.wt-collapsible {
+  display: flex;
+  flex-direction: column;
+  gap: var(--sp-3);
+  padding-bottom: var(--sp-3);
+}
+
+.wt-collapsible[hidden] {
+  display: none;
 }
 
 .form-error {
@@ -1371,8 +1419,9 @@ textarea {
   color: var(--muted);
 }
 
-/* Project picker rows (#59). Worktree rows are indented under their base
-   repository; rows stale beyond 7 days are dimmed but still selectable. */
+/* Working-directory picker (#95). Two steps: a grid of project boxes, then the
+   picked project's worktree choices. Stale beyond 7 days dims but stays
+   selectable. */
 .picker {
   display: flex;
   flex-direction: column;
@@ -1387,73 +1436,155 @@ textarea {
   width: 100%;
 }
 
-.project-row {
+/* `display` from `.field`/`.raw-wrap` outranks the UA sheet's `[hidden]`, so
+   step two and the raw-cwd hatch stayed visible while hidden. */
+.wt-step[hidden],
+.raw-wrap[hidden] {
+  display: none;
+}
+
+.picker.projects {
+  display: grid;
+  grid-template-columns: repeat(auto-fill, minmax(190px, 1fr));
+  align-content: start;
+  gap: var(--sp-2);
+  max-height: 300px;
+  padding: 1px;
+}
+
+.project-box {
+  display: flex;
+  flex-direction: column;
+  gap: 2px;
+  min-width: 0;
+  padding: var(--sp-2) var(--sp-3);
+  background: var(--surface-2);
+  border: 1px solid var(--border);
+  border-radius: var(--r-2);
+  color: var(--ink);
+  font-family: inherit;
+  text-align: left;
+  cursor: pointer;
+  transition:
+    border-color var(--dur-fast) var(--ease-out),
+    background var(--dur-fast) var(--ease-out);
+}
+
+.project-box:hover {
+  border-color: var(--border-strong);
+}
+
+.project-box.is-active {
+  border-color: var(--accent);
+  background: var(--accent-tint);
+}
+
+.project-box.is-stale {
+  opacity: 0.55;
+}
+
+.project-name {
+  font-size: var(--fs-13);
+  font-weight: 600;
+  overflow: hidden;
+  text-overflow: ellipsis;
+  white-space: nowrap;
+}
+
+/* The whole path, never abbreviated — it is what tells two projects sharing a
+   basename apart. Wraps rather than truncating so none of it is hidden. */
+.project-path {
+  font-family: var(--font-mono);
+  font-size: var(--fs-12);
+  line-height: 1.35;
+  color: var(--muted);
+  overflow-wrap: anywhere;
+}
+
+.project-meta {
+  font-family: var(--font-mono);
+  font-size: var(--fs-12);
+  color: var(--faint);
+  overflow: hidden;
+  text-overflow: ellipsis;
+  white-space: nowrap;
+}
+
+.project-meta:empty {
+  display: none;
+}
+
+.project-other {
+  align-self: flex-start;
+  padding: 4px 0;
+  min-height: 30px;
+  background: none;
+  border: 0;
+  color: var(--muted);
+  font-family: inherit;
+  font-size: var(--fs-13);
+  font-style: italic;
+  text-align: left;
+  cursor: pointer;
+}
+
+.project-other:hover {
+  color: var(--ink);
+}
+
+/* Step two: "+ new" (create one) or an existing worktree (run in it). */
+.picker.wt-choices {
+  max-height: 200px;
+}
+
+.wt-choice {
   display: flex;
   align-items: baseline;
   justify-content: space-between;
   gap: var(--sp-3);
+  min-height: 32px;
   padding: 6px var(--sp-3);
   background: var(--surface-2);
   border: 1px solid var(--border);
   border-radius: var(--r-2);
   color: var(--ink);
   font-family: inherit;
-  cursor: pointer;
   text-align: left;
+  cursor: pointer;
   transition:
     border-color var(--dur-fast) var(--ease-out),
     background var(--dur-fast) var(--ease-out);
 }
 
-.project-row:hover {
+.wt-choice:hover {
   border-color: var(--border-strong);
 }
 
-.project-row.is-active {
+.wt-choice.is-active {
   border-color: var(--accent);
   background: var(--accent-tint);
 }
 
-.project-row.is-worktree {
-  margin-left: var(--sp-4);
-}
-
-.project-row.is-stale {
-  opacity: 0.55;
-}
-
-.project-info {
-  display: flex;
-  align-items: baseline;
-  gap: var(--sp-2);
-  min-width: 0;
-}
-
-.project-name {
+.wt-choice-name {
+  flex: 0 0 auto;
   font-size: var(--fs-13);
   font-weight: 600;
   white-space: nowrap;
 }
 
-.recent-dir {
+.wt-choice-new .wt-choice-name {
   font-family: var(--font-mono);
-  font-size: var(--fs-12);
-  color: var(--muted);
-  overflow: hidden;
-  text-overflow: ellipsis;
-  white-space: nowrap;
+  color: var(--accent);
 }
 
-.recent-cmd {
-  flex: 0 0 auto;
+.wt-choice-sub {
+  min-width: 0;
   font-family: var(--font-mono);
   font-size: var(--fs-12);
+  line-height: 1.35;
   color: var(--muted);
-}
-
-.project-other .recent-dir {
-  font-family: inherit;
-  font-style: italic;
+  text-align: right;
+  overflow-wrap: anywhere;
 }
 
 .picker-empty {

web/src/tree.test.ts

@@ -95,3 +95,59 @@ describe("mergeLinear", () => {
     expect(merged.path).toBe("a/b");
   });
 });
+
+describe("worktree sessions group under their repository (#99)", () => {
+  /** A session the daemon spawned into a worktree of `repo`. */
+  function worktreeSession(id: string, repo: string, wt: string): Session {
+    return { ...session(id, wt), worktree: { path: wt, base_repo: repo } } as Session;
+  }
+
+  /** Top-level folder names, after linear chains are collapsed. */
+  function topFolders(root: TreeFolder): string[] {
+    return root.children.filter((c) => c.kind === "folder").map((c) => (c as TreeFolder).name);
+  }
+
+  it("nests under the repo, not the worktree directory", () => {
+    const root = buildTree(
+      [
+        worktreeSession(
+          "a",
+          "/home/n/tea/agent-skills",
+          "/home/n/tea/agent-skills/worktrees/largo-clarinet",
+        ),
+      ],
+      "/home/n",
+      "",
+    ) as TreeFolder;
+
+    expect(topFolders(root)).toEqual(["~/tea/agent-skills"]);
+    const repo = root.children[0] as TreeFolder;
+    expect(repo.children).toHaveLength(1);
+    expect(repo.children[0].kind).toBe("leaf");
+  });
+
+  it("puts a repo's plain and worktree sessions side by side", () => {
+    const root = buildTree(
+      [
+        session("plain", "/home/n/tea/agent-skills"),
+        worktreeSession(
+          "wt",
+          "/home/n/tea/agent-skills",
+          "/home/n/tea/agent-skills/worktrees/largo-clarinet",
+        ),
+      ],
+      "/home/n",
+      "",
+    ) as TreeFolder;
+
+    expect(topFolders(root)).toEqual(["~/tea/agent-skills"]);
+    const repo = root.children[0] as TreeFolder;
+    expect(repo.children).toHaveLength(2);
+    expect(repo.children.every((c) => c.kind === "leaf")).toBe(true);
+  });
+
+  it("leaves a session without a worktree where it is", () => {
+    const root = buildTree([session("a", "/home/n/tea/arr")], "/home/n", "") as TreeFolder;
+    expect(topFolders(root)).toEqual(["~/tea/arr"]);
+  });
+});

web/src/tree.ts

@@ -2,7 +2,7 @@
 // so it can be tested directly.
 
 import type { Session } from "./types.js";
-import { abbreviateCwd, sessionCwd, sessionName } from "./types.js";
+import { abbreviateCwd, sessionName, sessionTreePath } from "./types.js";
 
 export interface TreeFolder {
   kind: "folder";
@@ -30,7 +30,9 @@ export function buildTree(sessions: Session[], home: string | undefined, filter:
   const lc = filter.trim().toLowerCase();
 
   for (const s of sessions) {
-    const cwd = sessionCwd(s);
+    // Grouped by repository, so a worktree session lands under its repo
+    // rather than in a folder of its own (#99).
+    const cwd = sessionTreePath(s);
     const dir = cwd ? abbreviateCwd(cwd, home) : "";
     if (lc) {
       const haystack = `${sessionName(s)} ${dir}`.toLowerCase();

web/src/types.ts

@@ -9,8 +9,9 @@ export type IsoTimestamp = string;
 export type SessionStatus = "Running" | "Dead";
 
 /** Daemon-inferred activity dimension, orthogonal to `SessionStatus` (NAP-340).
- * Absent on payloads from daemons that predate the field. */
-export type ActivityState = "Active" | "Idle" | "AwaitingInput";
+ * Absent on payloads from daemons that predate the field. `Error` is only set
+ * when an agent reports failure (#105); the daemon never infers it. */
+export type ActivityState = "Active" | "Idle" | "AwaitingInput" | "Error";
 
 export interface Session {
   id: Uuid;
@@ -27,10 +28,30 @@ export interface Session {
   activity?: ActivityState;
   /** Wall-clock of the most recent observed PTY output (NAP-340). */
   last_activity_at?: IsoTimestamp;
+  /** Wall-clock of when the session entered its current `activity` state
+   * (#102) — distinct from `last_activity_at`, which only tracks PTY output.
+   * Defaults to the Unix epoch on payloads from daemons that predate the
+   * field. */
+  activity_since?: IsoTimestamp;
   /** The pane's *current* working directory, as the daemon's activity watcher
    * observed it (`#{pane_current_path}`) — distinct from `cwd` (the spawn dir).
    * Drives the directory-based session tree. Absent until first observed. */
   current_cwd?: string | null;
+  /** What currently blocks an unforced kill of this session (#83), as the
+   * daemon's watcher last probed it. Absent until probed and for sessions
+   * without a worktree; all counts default to 0 on the wire for older
+   * daemons. */
+  blocked_work?: InTheWay | null;
+  /** The worktree the daemon created for this session, absent when it did not
+   * create one. `base_repo` is the repository's main checkout, which is what
+   * the session tree groups by (#99). */
+  worktree?: SessionWorktree | null;
+}
+
+/** A session's daemon-created worktree (`SessionWorktree` on the wire). */
+export interface SessionWorktree {
+  path: string;
+  base_repo: string;
 }
 
 /** One directory's immediate subdirectories (NAP-329). */
@@ -113,7 +134,6 @@ export type Projects = Project[];
 export interface WorktreeSpec {
   base_repo: string;
   branch: string;
-  cleanup_on_kill?: boolean;
   /** When false, `branch` already exists and is checked out as-is (#61).
    * Defaults to true (create a new branch) on older daemons. */
   create_branch?: boolean;
@@ -181,6 +201,19 @@ export function reasonLabel(reason: RetainedReason): string {
   return reason;
 }
 
+/** #83: this session's blocked-work breakdown when something actually blocks
+ * an unforced kill; `null` while clear or not yet probed. Render it with
+ * {@link formatInTheWay} so every client phrases it identically. */
+export function sessionBlockers(s: Session): InTheWay | null {
+  const w = s.blocked_work;
+  if (!w) return null;
+  const blocked =
+    (w.uncommitted_files ?? 0) > 0 ||
+    (w.untracked_files ?? 0) > 0 ||
+    (w.unpushed_commits ?? 0) > 0;
+  return blocked ? w : null;
+}
+
 export interface CreateSessionRequest {
   cwd: string;
   command: string;
@@ -214,12 +247,23 @@ export function sessionName(s: Session): string {
 }
 
 /** The directory a session lives in: its live `current_cwd` if the daemon has
- * observed one, else the spawn `cwd`. Drives the directory-based session tree. */
+ * observed one, else the spawn `cwd`. */
 export function sessionCwd(s: Session): string | undefined {
   if (typeof s.current_cwd === "string" && s.current_cwd) return s.current_cwd;
   return s.cwd || undefined;
 }
 
+/** Where a session sits in the directory tree. A worktree session belongs to
+ * its repository, not to the worktree (#99): otherwise `~/tea/agent-skills`
+ * grows a `~/tea/agent-skills/worktrees/largo-clarinet` folder holding one
+ * session of the same name, and the repository stops being where you look for
+ * the work. `base_repo` is the main checkout — the daemon resolves it. */
+export function sessionTreePath(s: Session): string | undefined {
+  const repo = s.worktree?.base_repo;
+  if (typeof repo === "string" && repo) return repo;
+  return sessionCwd(s);
+}
+
 /** Collapse a daemon's home dir to `~`. `home` comes from `DaemonInfo.home_dir`;
  * absent/empty leaves the path untouched. Mirrors the CLI's `abbreviate_dir`. */
 export function abbreviateCwd(cwd: string, home?: string): string {

web/src/worktreeStep.test.ts

@@ -0,0 +1,233 @@
+// @vitest-environment happy-dom
+// Second step of the working-directory picker (#95). See the interaction rules
+// block in spawnForm.ts for what each choice means.
+import { afterEach, beforeEach, describe, expect, it, vi } from "vitest";
+
+import { createSpawnForm, type SpawnFormHandle, type SpawnFormValues } from "./spawnForm.js";
+import type { Project } from "./types.js";
+
+const MAESTRO: Project = {
+  path: "/home/user/tea/maestro",
+  name: "maestro",
+  is_worktree: false,
+  last_activity: "2026-08-20T10:00:00Z",
+  last_command: "claude",
+};
+
+const WT_A: Project = {
+  path: "/home/user/tea/maestro/worktrees/bulgarians",
+  name: "bulgarians",
+  is_worktree: true,
+  base_repo: MAESTRO.path,
+  last_activity: "2026-08-22T10:00:00Z",
+};
+
+const WT_B: Project = {
+  path: "/home/user/tea/maestro/worktrees/spawn-v2",
+  name: "spawn-v2",
+  is_worktree: true,
+  base_repo: MAESTRO.path,
+  last_activity: "2026-08-21T10:00:00Z",
+};
+
+const OTHER: Project = {
+  path: "/home/user/tea/rev",
+  name: "rev",
+  is_worktree: false,
+  last_activity: "2026-08-19T10:00:00Z",
+};
+
+function stubFetch(projects: Project[]): string[] {
+  const urls: string[] = [];
+  vi.stubGlobal(
+    "fetch",
+    vi.fn(async (input: RequestInfo | URL) => {
+      const url = String(input);
+      urls.push(url);
+      const body = url.includes("/api/projects")
+        ? projects
+        : url.includes("/api/names")
+          ? { names: ["amber-fox"] }
+          : url.includes("/api/branches")
+            ? []
+            : { hostname: "h", version: "0", home_dir: "/home/user", presets: [] };
+      return new Response(JSON.stringify(body), { status: 200 });
+    }),
+  );
+  return urls;
+}
+
+describe("spawnForm worktree step (#95)", () => {
+  let handle: SpawnFormHandle | null = null;
+  let urls: string[] = [];
+  let changes: SpawnFormValues[] = [];
+
+  beforeEach(() => {
+    vi.useFakeTimers({ now: Date.parse("2026-08-23T12:00:00Z") });
+    changes = [];
+  });
+
+  afterEach(() => {
+    handle?.destroy();
+    handle = null;
+    vi.unstubAllGlobals();
+    vi.useRealTimers();
+  });
+
+  const drain = async () => {
+    for (let i = 0; i < 40; i++) await Promise.resolve();
+  };
+
+  async function mount(projects: Project[]): Promise<HTMLFormElement> {
+    urls = stubFetch(projects);
+    handle = createSpawnForm({ onSuccess() {}, onChange: (v) => changes.push(v) });
+    document.body.appendChild(handle.el);
+    await drain();
+    return handle.el;
+  }
+
+  const step = (form: HTMLFormElement) => form.querySelector<HTMLElement>(".wt-step")!;
+  const choices = (form: HTMLFormElement) => [
+    ...form.querySelectorAll<HTMLButtonElement>(".wt-choice"),
+  ];
+  const activeChoice = (form: HTMLFormElement) =>
+    form.querySelector<HTMLButtonElement>(".wt-choice.is-active");
+  const box = (form: HTMLFormElement, path: string) =>
+    form.querySelector<HTMLButtonElement>(`.project-box[data-cwd="${path}"]`)!;
+  const toggle = (form: HTMLFormElement) =>
+    form.querySelector<HTMLInputElement>("input[name=worktree_enabled]")!;
+
+  it("hides the worktree step until a project is picked", async () => {
+    const form = await mount([MAESTRO, WT_A]);
+    expect(step(form).hidden).toBe(true);
+    expect(choices(form)).toEqual([]);
+
+    box(form, MAESTRO.path).click();
+    await drain();
+
+    expect(step(form).hidden).toBe(false);
+  });
+
+  it("lists '+ new' first and selected by default, then the project's worktrees", async () => {
+    const form = await mount([MAESTRO, WT_A, WT_B]);
+    box(form, MAESTRO.path).click();
+    await drain();
+
+    const labels = choices(form).map((c) => c.querySelector(".wt-choice-name")!.textContent);
+    expect(labels).toEqual(["+ new", "bulgarians", "spawn-v2"]);
+    expect(activeChoice(form)!.dataset.kind).toBe("new");
+  });
+
+  it("taking the '+ new' default runs in the repo with the create toggle on", async () => {
+    const form = await mount([MAESTRO, WT_A]);
+    box(form, MAESTRO.path).click();
+    await drain();
+
+    expect(changes.at(-1)!.cwd).toBe(MAESTRO.path);
+    expect(changes.at(-1)!.worktreeEnabled).toBe(true);
+    expect(toggle(form).checked).toBe(true);
+    expect(form.querySelector<HTMLElement>(".wt-repo")!.textContent).toContain(MAESTRO.path);
+    // The scan already knows the repo — no probe.
+    expect(urls.some((u) => u.includes("/api/gitroot"))).toBe(false);
+  });
+
+  it("picking an existing worktree runs in it with the create toggle off (#91)", async () => {
+    const form = await mount([MAESTRO, WT_A, WT_B]);
+    box(form, MAESTRO.path).click();
+    await drain();
+
+    const existing = choices(form).find((c) => c.dataset.cwd === WT_A.path)!;
+    existing.click();
+    await drain();
+
+    expect(changes.at(-1)!.cwd).toBe(WT_A.path);
+    expect(changes.at(-1)!.worktreeEnabled).toBe(false);
+    expect(toggle(form).checked).toBe(false);
+    expect(form.querySelector<HTMLElement>(".wt-body")!.hidden).toBe(true);
+    expect(existing.classList.contains("is-active")).toBe(true);
+    // Still no probe: the scan reported this worktree's repo membership.
+    expect(urls.some((u) => u.includes("/api/gitroot"))).toBe(false);
+    // The project box stays marked — it is what the worktree list belongs to.
+    expect(box(form, MAESTRO.path).classList.contains("is-active")).toBe(true);
+  });
+
+  it("switching back to '+ new' re-enables the create toggle", async () => {
+    const form = await mount([MAESTRO, WT_A]);
+    box(form, MAESTRO.path).click();
+    await drain();
+    choices(form)
+      .find((c) => c.dataset.cwd === WT_A.path)!
+      .click();
+    await drain();
+
+    choices(form)
+      .find((c) => c.dataset.kind === "new")!
+      .click();
+    await drain();
+
+    expect(changes.at(-1)!.cwd).toBe(MAESTRO.path);
+    expect(changes.at(-1)!.worktreeEnabled).toBe(true);
+    expect(toggle(form).checked).toBe(true);
+  });
+
+  it("repopulates and resets to '+ new' when another project is picked", async () => {
+    const form = await mount([MAESTRO, WT_A, OTHER]);
+    box(form, MAESTRO.path).click();
+    await drain();
+    choices(form)
+      .find((c) => c.dataset.cwd === WT_A.path)!
+      .click();
+    await drain();
+
+    box(form, OTHER.path).click();
+    await drain();
+
+    expect(choices(form).map((c) => c.dataset.kind)).toEqual(["new"]);
+    expect(activeChoice(form)!.dataset.kind).toBe("new");
+    expect(changes.at(-1)!.cwd).toBe(OTHER.path);
+    expect(changes.at(-1)!.worktreeEnabled).toBe(true);
+  });
+
+  it("defaults to the worktree itself when the box is a linked worktree (#91)", async () => {
+    // No main checkout in the scan, so the orphan worktree is its own box.
+    const form = await mount([WT_A]);
+    box(form, WT_A.path).click();
+    await drain();
+
+    expect(activeChoice(form)!.dataset.cwd).toBe(WT_A.path);
+    expect(changes.at(-1)!.cwd).toBe(WT_A.path);
+    expect(changes.at(-1)!.worktreeEnabled).toBe(false);
+    expect(toggle(form).checked).toBe(false);
+    expect(form.querySelector<HTMLElement>(".wt-body")!.hidden).toBe(true);
+  });
+
+  it("hides the worktree step again when the operator takes the raw-input hatch", async () => {
+    const form = await mount([MAESTRO, WT_A]);
+    box(form, MAESTRO.path).click();
+    await drain();
+    expect(step(form).hidden).toBe(false);
+
+    form.querySelector<HTMLButtonElement>(".project-other")!.click();
+    await drain();
+
+    expect(step(form).hidden).toBe(true);
+    expect(choices(form)).toEqual([]);
+    expect(form.querySelector(".project-box.is-active")).toBeNull();
+  });
+
+  it("restores the picked worktree from a draft seed", async () => {
+    urls = stubFetch([MAESTRO, WT_A, WT_B]);
+    handle = createSpawnForm({
+      onSuccess() {},
+      seed: { cwd: WT_A.path, cwdRawVisible: false, worktreeEnabled: false },
+    });
+    document.body.appendChild(handle.el);
+    await drain();
+    const form = handle.el;
+
+    expect(step(form).hidden).toBe(false);
+    expect(activeChoice(form)!.dataset.cwd).toBe(WT_A.path);
+    expect(box(form, MAESTRO.path).classList.contains("is-active")).toBe(true);
+    expect(toggle(form).checked).toBe(false);
+  });
+});