merge: surface blocked work before the kill is attempted

Closes #83

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,
@@ -168,7 +163,6 @@ mod tests {
             "/repos/foo",
             "--branch",
             "feat/x",
-            "--cleanup-on-kill",
             "-e",
             "FOO=bar",
             "-e",
@@ -179,7 +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()),]
@@ -189,27 +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.

crates/maestro-cli/src/dispatch.rs

@@ -62,6 +62,11 @@ pub async fn dispatch(
             run_attach_url(&daemon.attach_url(args.session_id)?, detach).await?;
         }
         Command::Kill(args) => {
+            // #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 {
@@ -99,6 +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,
@@ -94,8 +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 {
@@ -116,15 +115,28 @@ 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 {
@@ -165,6 +177,7 @@ mod tests {
             activity: Default::default(),
             last_activity_at: chrono::Utc::now(),
             current_cwd: None,
+            blocked_work: None,
         }
     }
 
@@ -225,4 +238,37 @@ 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-daemon/src/session.rs

@@ -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 {
@@ -344,6 +351,9 @@ impl SessionManager {
             last_activity_at: 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) {
@@ -489,6 +499,17 @@ 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);
@@ -496,6 +517,9 @@ 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 {
@@ -505,6 +529,11 @@ 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;
+                }
             }
         });
     }
@@ -541,6 +570,7 @@ impl SessionManager {
                     last_activity_at: Utc::now(),
 
                     current_cwd: None,
+                    blocked_work: None,
                 },
             };
             let fifo_path = self.inner.fifo_dir.join(format!("{id}.fifo"));
@@ -809,6 +839,61 @@ 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 settle its worktree per the natural-exit rule (#82).
 ///
@@ -852,10 +937,13 @@ async fn mark_session_dead(inner: &Arc<Inner>, id: Uuid) {
 
     if let Some(wt) = &worktree {
         if settle_worktree_on_exit(inner, id, wt, branch).await {
-            session.worktree = None;
+            // 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;

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/local_api.rs

@@ -363,7 +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,
             }),
         })
@@ -417,7 +416,6 @@ async fn delete_with_force_ends_the_session_and_answers_what_was_retained() {
             worktree: Some(WorktreeSpec {
                 base_repo: repo.path().to_path_buf(),
                 branch: "feat/guarded".into(),
-                cleanup_on_kill: true,
                 create_branch: true,
             }),
         })

crates/maestro-daemon/tests/session_manager.rs

@@ -367,6 +367,67 @@ async fn liveness_watcher_marks_dead_sessions_and_keeps_them_until_dismissed() {
     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.
@@ -387,7 +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,
             }),
         })
@@ -425,7 +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,
             }),
         })
@@ -489,7 +548,6 @@ 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,
             }),
         })
@@ -541,7 +599,6 @@ async fn force_killing_a_guarded_worktree_retains_it_in_the_store() {
             worktree: Some(WorktreeSpec {
                 base_repo: repo.path().to_path_buf(),
                 branch: "feat/forced".into(),
-                cleanup_on_kill: true,
                 create_branch: true,
             }),
         })
@@ -607,7 +664,6 @@ async fn force_on_a_clear_worktree_removes_it_as_usual() {
             worktree: Some(WorktreeSpec {
                 base_repo: repo.path().to_path_buf(),
                 branch: "feat/clear".into(),
-                cleanup_on_kill: true,
                 create_branch: true,
             }),
         })
@@ -650,7 +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,
             }),
         })
@@ -693,7 +748,6 @@ async fn natural_exit_of_a_guarded_worktree_retains_it_in_the_store() {
             worktree: Some(WorktreeSpec {
                 base_repo: repo.path().to_path_buf(),
                 branch: "feat/exited".into(),
-                cleanup_on_kill: true,
                 create_branch: true,
             }),
         })
@@ -728,7 +782,8 @@ async fn natural_exit_of_a_guarded_worktree_retains_it_in_the_store() {
     // 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 {
-        fx.manager.snapshot().await[0].worktree.is_none()
+        let s = &fx.manager.snapshot().await[0];
+        s.worktree.is_none() && s.blocked_work.is_none()
     })
     .await;
     let snap = fx.manager.snapshot().await;
@@ -767,7 +822,6 @@ async fn natural_exit_of_a_pristine_worktree_removes_it() {
             worktree: Some(WorktreeSpec {
                 base_repo: repo.path().to_path_buf(),
                 branch: "feat/clean".into(),
-                cleanup_on_kill: true,
                 create_branch: true,
             }),
         })
@@ -829,7 +883,6 @@ async fn natural_exit_without_a_retained_store_destroys_nothing() {
             worktree: Some(WorktreeSpec {
                 base_repo: repo.path().to_path_buf(),
                 branch: "feat/nostore".into(),
-                cleanup_on_kill: true,
                 create_branch: true,
             }),
         })

crates/maestro-daemon/tests/sidecar.rs

@@ -28,6 +28,7 @@ fn sample(id: Uuid) -> Session {
         activity: Default::default(),
         last_activity_at: 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;
@@ -64,6 +65,20 @@ impl TestClient {
         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> {
         Ok(self.daemon.list_projects().await?)
     }

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/lib.rs

@@ -87,6 +87,13 @@ 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.
@@ -119,11 +126,6 @@ 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`.
@@ -536,6 +538,7 @@ mod tests {
                 .unwrap()
                 .with_timezone(&Utc),
             current_cwd: Some(PathBuf::from("/home/naps62/projects/maestro/crates")),
+            blocked_work: None,
         }
     }
 
@@ -555,6 +558,34 @@ 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]
@@ -594,7 +625,6 @@ mod tests {
             worktree: Some(WorktreeSpec {
                 base_repo: PathBuf::from("/home/naps62/projects/maestro"),
                 branch: "feat/foo".into(),
-                cleanup_on_kill: true,
                 create_branch: true,
             }),
         };
@@ -624,7 +654,6 @@ mod tests {
         });
         let spec: WorktreeSpec = serde_json::from_value(json).unwrap();
         assert!(spec.create_branch);
-        assert!(spec.cleanup_on_kill);
     }
 
     #[test]
@@ -632,7 +661,6 @@ 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));

crates/maestro-testing/src/lib.rs

@@ -43,6 +43,7 @@ pub fn session(id: Uuid, cwd: &str, command: &str) -> Session {
         activity: Default::default(),
         last_activity_at: Utc::now(),
         current_cwd: None,
+        blocked_work: None,
     }
 }
 

crates/maestro-tui/src/app.rs

@@ -1107,6 +1107,7 @@ mod tests {
                 activity: Default::default(),
                 last_activity_at: Utc::now(),
                 current_cwd: None,
+                blocked_work: None,
             }],
         });
         app.dispatch(Action::SidebarNext);
@@ -1614,6 +1615,7 @@ mod tests {
                 last_activity_at: chrono::Utc::now(),
 
                 current_cwd: None,
+                blocked_work: None,
             }],
         });
         app.dispatch(Action::KillHighlighted);

crates/maestro-tui/src/catalog.rs

@@ -195,6 +195,7 @@ mod tests {
             activity: Default::default(),
             last_activity_at: chrono::Utc::now(),
             current_cwd: None,
+            blocked_work: None,
         }
     }
 

crates/maestro-tui/src/draft.rs

@@ -549,7 +549,6 @@ impl DraftPane {
                 WorktreeSpec {
                     base_repo,
                     branch: branch.to_string(),
-                    cleanup_on_kill: true,
                     create_branch: true,
                 }
             }
@@ -562,7 +561,6 @@ impl DraftPane {
                 WorktreeSpec {
                     base_repo,
                     branch: name,
-                    cleanup_on_kill: true,
                     create_branch: false,
                 }
             }
@@ -1689,7 +1687,6 @@ mod tests {
         assert_eq!(wt.base_repo, PathBuf::from("/repos/maestro"));
         assert_eq!(wt.branch, "crimson-otter", "branch defaults to the name");
         assert!(wt.create_branch);
-        assert!(wt.cleanup_on_kill);
     }
 
     #[test]

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/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

@@ -52,6 +52,13 @@ impl Sidebar {
                 (SessionStatus::Running, false) => "○",
             };
             let label = name_for(s);
+            // #83: a session whose worktree blocks a kill gets a warning
+            // glyph; the kill confirm names the specifics.
+            let blocked = s
+                .blocked_work
+                .filter(|b| !b.is_clear())
+                .map(|_| " ⚠")
+                .unwrap_or_default();
             let style = if self.highlight == Some(s.id) {
                 Style::default().add_modifier(Modifier::REVERSED)
             } else {
@@ -59,7 +66,7 @@ impl Sidebar {
             };
             lines.push(Line::from(vec![
                 Span::raw("  "),
-                Span::styled(format!("{glyph} {label}"), style),
+                Span::styled(format!("{glyph} {label}{blocked}"), style),
             ]));
         }
         f.render_widget(Paragraph::new(lines), inner);
@@ -99,6 +106,7 @@ mod tests {
             activity: Default::default(),
             last_activity_at: chrono::Utc::now(),
             current_cwd: None,
+            blocked_work: None,
         }
     }
 
@@ -172,6 +180,40 @@ mod tests {
         assert!(line.contains('✗'), "expected dead glyph in: {line:?}");
     }
 
+    /// #83: a session whose worktree blocks a kill carries the warning glyph;
+    /// a clear or unprobed one does not.
+    #[test]
+    fn blocked_session_gets_a_warning_glyph() {
+        use maestro_protocol::InTheWay;
+
+        let mut blocked = session_named(1, "claude");
+        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 rendered = render_to_string(&sb, 40, 8);
+        let line = rendered
+            .lines()
+            .find(|l| l.contains("claude"))
+            .expect("blocked row");
+        assert!(line.contains('⚠'), "expected warning glyph in: {line:?}");
+        for name in ["bash", "vim"] {
+            let line = rendered
+                .lines()
+                .find(|l| l.contains(name))
+                .expect("clear row");
+            assert!(!line.contains('⚠'), "{name} must not warn: {line:?}");
+        }
+    }
+
     #[test]
     fn falls_back_to_command_when_name_metadata_is_absent() {
         let s = Session {
@@ -188,6 +230,7 @@ mod tests {
             last_activity_at: chrono::Utc::now(),
 
             current_cwd: None,
+            blocked_work: None,
         };
         let sb = Sidebar {
             sessions: vec![s],

web/src/catalog.test.ts

@@ -0,0 +1,106 @@
+// @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"?']);
+  });
+});

web/src/catalog.ts

@@ -3,7 +3,7 @@ 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 type { TreeNode } from "./tree.js";
 import { buildTree } from "./tree.js";
 import { createThemeToggle } from "./theme.js";
@@ -64,10 +64,14 @@ function renderNode(node: TreeNode, depth: number): HTMLElement {
   // 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;
+  // #83: warn on the row itself, in `formatInTheWay`'s shared phrasing, so
+  // "this will be refused" is visible before the kill is attempted.
+  const blockers = sessionBlockers(s);
   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>`}
+    ${blockers ? `<span class="leaf-badge leaf-blocked" title="Kill will be refused unless forced">⚠ ${escapeHtml(formatInTheWay(blockers))}</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 ${escapeHtml(name)}">✕</button>
@@ -83,7 +87,12 @@ function renderNode(node: TreeNode, depth: number): HTMLElement {
   killBtn.addEventListener("click", async (ev) => {
     ev.preventDefault();
     ev.stopPropagation();
-    if (!confirm(`Kill session "${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) {

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/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

@@ -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",

web/src/styles.css

@@ -831,6 +831,13 @@ textarea {
   flex: 0 0 auto;
 }
 
+/* #83: the session row's blocked-work warning — an unforced kill will be
+   refused, and the operator should see that before pressing the button. */
+.leaf-badge.leaf-blocked {
+  color: var(--warn, #b45309);
+  border-color: var(--warn, #b45309);
+}
+
 .leaf-actions {
   position: absolute;
   right: var(--sp-1);

web/src/types.ts

@@ -31,6 +31,11 @@ export interface Session {
    * 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;
 }
 
 /** One directory's immediate subdirectories (NAP-329). */
@@ -113,7 +118,6 @@ 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 +185,19 @@ 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;