CHANGELOG.md

@@ -6,6 +6,14 @@ loosely follows [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
 
 ## [Unreleased]
 
+## [0.0.7] - 2026-05-18
+
+### Added
+- The top tab bar now prefixes each agent tab's label with its
+  idle-state glyph (✕ error, ? permission, ◐ thinking, ○ idle, ●
+  working), matching the sidebar's vocabulary so the state of every
+  open agent is visible without opening or focusing each tab.
+
 ### Changed
 - Built-in agent presets (`claude`, `codex`, `opencode`) now live in
   memory and user preset files merge over them by name instead of
@@ -33,6 +41,10 @@ loosely follows [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
   repaint.
 - Removed the redundant "Back to Settings" row from the
   Agents / Auto-summarization settings screen.
+- Pending `timer_*` entries are now cancelled when their owning or
+  watched child is closed via `close_process`, preventing stale
+  timer bodies from being re-delivered to the orchestrator pane
+  after the work has already been handled.
 
 ## [0.0.6] - 2026-05-15
 

TODO.md

@@ -1 +0,0 @@
-- [ ] We should show idle state in the top tab bar as well

internal/app/app.go

@@ -829,14 +829,21 @@ func (st *uiState) OnChildSpawned(c *Child) {
 	st.drawStatusLine()
 }
 
-// OnChildStateChanged repaints the sidebar whenever a child's
-// idle-state badge flips. Cheap — the badge is the only chrome that
-// reflects state today, and drawSidebar bails when the cached frame
-// hasn't changed.
+// OnChildStateChanged repaints the sidebar and tab bar whenever a
+// child's idle-state badge flips. Cheap — both draws bail when the
+// cached frame hasn't changed.
 func (st *uiState) OnChildStateChanged(string, IdleState) {
+	st.drawTabBar()
 	st.drawSidebar()
 }
 
+// OnChildClosed is the explicit-removal hook (close_process or the
+// terminal-corpse cleanup in reapChild). The UI already reflects
+// removals via the OnChildExited path and the children-map view, so
+// this is a no-op here — the timerManager is the consumer that
+// cares.
+func (st *uiState) OnChildClosed(string) {}
+
 // OnChildExited drops focus and shows the empty state if it was the
 // focused child.
 func (st *uiState) OnChildExited(c *Child) {

internal/app/debug.go

@@ -111,6 +111,13 @@ func (d *debugCapture) OnChildStateChanged(id string, state IdleState) {
 	})
 }
 
+func (d *debugCapture) OnChildClosed(id string) {
+	d.writeEvent("child_closed", map[string]any{
+		"time": time.Now().Format(time.RFC3339Nano),
+		"id":   id,
+	})
+}
+
 func (d *debugCapture) OnPTYOut(childID string, chunk []byte) {
 	if len(chunk) == 0 {
 		return

internal/app/host.go

@@ -86,10 +86,10 @@ func newToolHost(sess *Session, pads *scratchpad.Store, launcher *Launcher, pres
 	return h
 }
 
-// timerListenerAdapter forwards OnChildStateChanged into the timer
-// manager and ignores the other ChildEventListener methods. The
-// session's listener API is by-interface, so we wrap the manager
-// rather than make it implement the full surface.
+// timerListenerAdapter forwards OnChildStateChanged and OnChildClosed
+// into the timer manager and ignores the other ChildEventListener
+// methods. The session's listener API is by-interface, so we wrap
+// the manager rather than make it implement the full surface.
 type timerListenerAdapter struct{ m *timerManager }
 
 func (a timerListenerAdapter) OnChildSpawned(*Child)   {}
@@ -98,6 +98,9 @@ func (a timerListenerAdapter) OnPTYOut(string, []byte) {}
 func (a timerListenerAdapter) OnChildStateChanged(id string, st IdleState) {
 	a.m.onChildStateChanged(id, st)
 }
+func (a timerListenerAdapter) OnChildClosed(id string) {
+	a.m.onChildClosed(id)
+}
 
 func (h *toolHost) SetSize(cols, rows uint16) {
 	h.sizeMu.Lock()
@@ -553,6 +556,7 @@ func (n *chunkNotifier) OnPTYOut(id string, chunk []byte) {
 	}
 }
 func (n *chunkNotifier) OnChildStateChanged(string, IdleState) {}
+func (n *chunkNotifier) OnChildClosed(string)                  {}
 
 func (h *toolHost) GetProcessPorts(callerID, processID string) ([]mcp.PortSighting, error) {
 	c := h.sess.FindChild(processID)

internal/app/session.go

@@ -91,6 +91,12 @@ type ChildEventListener interface {
 	// updates a child's IdleState. Listeners use this to repaint the
 	// sidebar badge and to evaluate idle-aware timers.
 	OnChildStateChanged(childID string, state IdleState)
+	// OnChildClosed fires when a child is being removed from the
+	// session (either via close_process, or — for agent/terminal
+	// kinds — when the PTY exits and the entry will never be
+	// restarted). It signals that any pending references to childID
+	// (e.g. timers owned by or watching it) should be dropped.
+	OnChildClosed(childID string)
 }
 
 func NewSession(projectDir, projectKey string) *Session {
@@ -167,6 +173,12 @@ func (s *Session) emitStateChanged(id string, state IdleState) {
 	}
 }
 
+func (s *Session) emitClosed(id string) {
+	for _, l := range s.listenersSnapshot() {
+		l.OnChildClosed(id)
+	}
+}
+
 func (s *Session) ChildEnv() []string {
 	env := os.Environ()
 	// Mark patterm-owned PTYs so a recursive `patterm` invocation can
@@ -374,6 +386,11 @@ func (s *Session) Close(id string, sig syscall.Signal) error {
 		}
 	}
 	s.mu.Unlock()
+	// Notify listeners outside s.mu so they can take their own locks
+	// without inversion. Timer manager uses this to drop pending
+	// timers owned by or watching the closed child — otherwise the
+	// next classifier tick can deliver a stale fire to the parent.
+	s.emitClosed(id)
 	s.forgetPersisted(id)
 	return nil
 }
@@ -486,6 +503,7 @@ func (s *Session) reapChild(c *Child, runID uint64) {
 			}
 		}
 		s.mu.Unlock()
+		s.emitClosed(c.ID)
 	}
 }
 

internal/app/tabbar.go

@@ -62,6 +62,8 @@ func (st *uiState) drawTabBar() {
 		startCol   int
 		width      int
 		label      string
+		glyph      string
+		glyphStyle string
 		active     bool
 	}
 	activeTab := -1
@@ -115,9 +117,16 @@ func (st *uiState) drawTabBar() {
 			if i < extra {
 				w++
 			}
+			active := c.ID == focus
+			glyph, glyphStyle := tabIdleGlyph(c.IdleState(), active)
 			label := c.DisplayName()
 			labelW := utf8.RuneCountInString(label)
-			maxLabelW := w - 2 // one pad on each side
+			// Reserve room for the glyph + its trailing space when present
+			// (1 + 1 runes), on top of the one-cell pad on each side.
+			maxLabelW := w - 2
+			if glyph != "" {
+				maxLabelW -= 2
+			}
 			if maxLabelW < 1 {
 				maxLabelW = 1
 			}
@@ -133,7 +142,9 @@ func (st *uiState) drawTabBar() {
 				startCol:   col,
 				width:      w,
 				label:      label,
-				active:   c.ID == focus,
+				glyph:      glyph,
+				glyphStyle: glyphStyle,
+				active:     active,
 			})
 			if tabs[len(tabs)-1].active {
 				activeTab = len(tabs) - 1
@@ -155,23 +166,37 @@ func (st *uiState) drawTabBar() {
 	fmt.Fprintf(&b, "\x1b[3;1H\x1b[%dX", width)
 
 	for _, t := range tabs {
-		// Row 1: centre-ish label inside the tab cell.
+		// Row 1: centre-ish glyph+label inside the tab cell.
 		labelW := utf8.RuneCountInString(t.label)
-		leftPad := (t.width - labelW) / 2
+		visibleW := labelW
+		if t.glyph != "" {
+			visibleW += 2 // glyph + separator space
+		}
+		leftPad := (t.width - visibleW) / 2
 		if leftPad < 1 {
 			leftPad = 1
 		}
-		rightPad := t.width - labelW - leftPad
+		rightPad := t.width - visibleW - leftPad
 		if rightPad < 0 {
 			rightPad = 0
 		}
-		fmt.Fprintf(&b, "\x1b[1;%dH", t.startCol)
+		cellStyle := styleHint
 		if t.active {
-			b.WriteString(styleActive)
-		} else {
-			b.WriteString(styleHint)
+			cellStyle = styleActive
 		}
+		fmt.Fprintf(&b, "\x1b[1;%dH", t.startCol)
+		b.WriteString(cellStyle)
 		b.WriteString(strings.Repeat(" ", leftPad))
+		if t.glyph != "" {
+			// Glyph uses its own colour so error/permission states pop
+			// regardless of tab focus, matching the sidebar's vocabulary.
+			b.WriteString(styleReset)
+			b.WriteString(t.glyphStyle)
+			b.WriteString(t.glyph)
+			b.WriteString(styleReset)
+			b.WriteString(cellStyle)
+			b.WriteString(" ")
+		}
 		b.WriteString(t.label)
 		b.WriteString(strings.Repeat(" ", rightPad))
 		b.WriteString(styleReset)
@@ -226,3 +251,29 @@ func (st *uiState) drawTabBar() {
 	defer st.outMu.Unlock()
 	fmt.Fprintf(os.Stdout, "\x1b7%s\x1b8", frame)
 }
+
+// tabIdleGlyph returns the one-rune state indicator (and its SGR style)
+// to render before a tab's label. Mirrors the sidebar's vocabulary so
+// users learn the symbols in one place: ✕ error, ? permission, ◐
+// thinking, ○ idle, ● working. Returns ("", "") for StateUnknown so the
+// first frame after spawn doesn't show a misleading badge.
+func tabIdleGlyph(state IdleState, active bool) (string, string) {
+	base := styleHint
+	if active {
+		base = styleAccent
+	}
+	switch state {
+	case StateError:
+		return "✕", styleError
+	case StatePermission:
+		return "?", styleAccent
+	case StateThinking:
+		return "◐", base
+	case StateIdle:
+		return "○", base
+	case StateWorking:
+		return "●", base
+	default:
+		return "", ""
+	}
+}

internal/app/timers.go

@@ -296,6 +296,65 @@ func (m *timerManager) onChildStateChanged(childID string, state IdleState) {
 	}
 }
 
+// onChildClosed drops pending timer references to childID. Called
+// from Session.Close (and the terminal-corpse cleanup in reapChild)
+// via the session listener bus — a deliberate signal from the host
+// that childID is gone and the parent is not waiting on it anymore.
+//
+// Semantics:
+//   - timers owned by childID are cancelled and deleted: their owner
+//     is gone, so even if defaultFireFn's IsLive guard would no-op
+//     the delivery, the entry has no business surviving a close.
+//   - timers watching childID have childID pruned from t.watched
+//     (and t.idleBaseline). If t.watched becomes empty the timer is
+//     cancelled and deleted; we deliberately do NOT synthesise a
+//     fire here. The parent already received any legitimate idle
+//     transition before close_process — see allWatchedIdleLocked's
+//     "treat as satisfied" comment, which only applies to a
+//     concurrent re-evaluation, not to this explicit-removal hook.
+//
+// The natural-exit path (reapChild → emitExit for agent/command
+// kinds) is NOT routed through here: the classifier emits a final
+// idle transition on exit, which fires and deletes any watching
+// timers exactly once. Cancelling on exit would swallow that
+// legitimate fire and leave the parent never notified.
+func (m *timerManager) onChildClosed(childID string) {
+	m.mu.Lock()
+	defer m.mu.Unlock()
+	for id, t := range m.timers {
+		if t.ownerID == childID {
+			if t.rt != nil {
+				t.rt.Stop()
+				t.rt = nil
+			}
+			t.status = timerStatusCanceled
+			delete(m.timers, id)
+			continue
+		}
+		if !contains(t.watched, childID) {
+			continue
+		}
+		pruned := t.watched[:0]
+		for _, w := range t.watched {
+			if w != childID {
+				pruned = append(pruned, w)
+			}
+		}
+		t.watched = pruned
+		if t.idleBaseline != nil {
+			delete(t.idleBaseline, childID)
+		}
+		if len(t.watched) == 0 {
+			if t.rt != nil {
+				t.rt.Stop()
+				t.rt = nil
+			}
+			t.status = timerStatusCanceled
+			delete(m.timers, id)
+		}
+	}
+}
+
 // allWatchedIdleLocked reports whether every watched child is now
 // idle. Called with m.mu held — uses live Child.IdleState() under the
 // child's own atomic, not under m.mu.

internal/app/timers_test.go

@@ -411,3 +411,178 @@ func TestTimerRecordsRemovedOnIdleFire(t *testing.T) {
 		t.Fatalf("fired idle timer %s was not removed from registry", resp.ID)
 	}
 }
+
+// TestTimerCloseChildPrunesWatched covers the happy partial-prune
+// case: an idle_any timer watches two children, one is closed, the
+// timer stays pending and the remaining child can still satisfy it.
+func TestTimerCloseChildPrunesWatched(t *testing.T) {
+	sess, mgr, rec := newTestManager(t)
+	owner := fakeChild("p_owner")
+	a := fakeChild("p_a")
+	b := fakeChild("p_b")
+	addChild(sess, owner)
+	addChild(sess, a)
+	addChild(sess, b)
+	working := StateWorking
+	a.idleState.Store(&working)
+	b.idleState.Store(&working)
+
+	resp, err := mgr.TimerFireWhenIdleAny("p_owner", "one done", "", []string{"p_a", "p_b"}, 0)
+	if err != nil {
+		t.Fatalf("TimerFireWhenIdleAny: %v", err)
+	}
+
+	mgr.onChildClosed("p_a")
+
+	mgr.mu.Lock()
+	t1, ok := mgr.timers[resp.ID]
+	if !ok {
+		mgr.mu.Unlock()
+		t.Fatalf("timer was removed but still has live watched")
+	}
+	watched := append([]string(nil), t1.watched...)
+	mgr.mu.Unlock()
+	if len(watched) != 1 || watched[0] != "p_b" {
+		t.Fatalf("watched after close: %v, want [p_b]", watched)
+	}
+	if got := rec.snapshot(); len(got) != 0 {
+		t.Fatalf("close synthesised a fire: %+v", got)
+	}
+
+	// p_b can still satisfy the timer.
+	idle := StateIdle
+	b.idleState.Store(&idle)
+	mgr.onChildStateChanged("p_b", StateIdle)
+	if got := rec.snapshot(); len(got) != 1 || got[0].Body != "one done" {
+		t.Fatalf("post-prune fire: %+v", got)
+	}
+}
+
+// TestTimerCloseLastWatchedCancels is the regression for the
+// reported stale-fire symptom: the only watched child is closed,
+// so the timer must be cancelled — no synthetic fire, and the
+// registry entry must be gone so a trailing classifier tick for the
+// removed child cannot re-deliver later.
+func TestTimerCloseLastWatchedCancels(t *testing.T) {
+	sess, mgr, rec := newTestManager(t)
+	owner := fakeChild("p_owner")
+	a := fakeChild("p_a")
+	addChild(sess, owner)
+	addChild(sess, a)
+	working := StateWorking
+	a.idleState.Store(&working)
+
+	resp, err := mgr.TimerFireWhenIdleAny("p_owner", "stale body", "", []string{"p_a"}, 0)
+	if err != nil {
+		t.Fatalf("TimerFireWhenIdleAny: %v", err)
+	}
+
+	mgr.onChildClosed("p_a")
+
+	mgr.mu.Lock()
+	_, stillThere := mgr.timers[resp.ID]
+	mgr.mu.Unlock()
+	if stillThere {
+		t.Fatalf("timer with no remaining watched should be removed")
+	}
+	if got := rec.snapshot(); len(got) != 0 {
+		t.Fatalf("close synthesised a fire: %+v", got)
+	}
+
+	// Simulate the trailing classifier tick for the now-closed child —
+	// must not fire.
+	mgr.onChildStateChanged("p_a", StateIdle)
+	if got := rec.snapshot(); len(got) != 0 {
+		t.Fatalf("trailing state change re-fired: %+v", got)
+	}
+}
+
+// TestTimerCloseChildIdleAllPartialPrune mirrors the idle_any
+// partial-prune for idle_all: pruning a watched child shrinks the
+// list; the remaining child going idle then satisfies the timer.
+func TestTimerCloseChildIdleAllPartialPrune(t *testing.T) {
+	sess, mgr, rec := newTestManager(t)
+	owner := fakeChild("p_owner")
+	a := fakeChild("p_a")
+	b := fakeChild("p_b")
+	addChild(sess, owner)
+	addChild(sess, a)
+	addChild(sess, b)
+	working := StateWorking
+	a.idleState.Store(&working)
+	b.idleState.Store(&working)
+
+	resp, err := mgr.TimerFireWhenIdleAll("p_owner", "all done", "", []string{"p_a", "p_b"}, 0)
+	if err != nil {
+		t.Fatalf("TimerFireWhenIdleAll: %v", err)
+	}
+	if resp.Status != "pending" {
+		t.Fatalf("status: got %q want pending", resp.Status)
+	}
+
+	mgr.onChildClosed("p_a")
+
+	idle := StateIdle
+	b.idleState.Store(&idle)
+	mgr.onChildStateChanged("p_b", StateIdle)
+	if got := rec.snapshot(); len(got) != 1 || got[0].Body != "all done" {
+		t.Fatalf("idle_all after partial prune: %+v", got)
+	}
+}
+
+// TestTimerCloseOwnerCancelsDelay ensures a delay timer is dropped
+// when its owner is closed: no delivery, registry empty, the
+// underlying time.Timer is stopped.
+func TestTimerCloseOwnerCancelsDelay(t *testing.T) {
+	sess, mgr, rec := newTestManager(t)
+	c := fakeChild("p_owner")
+	addChild(sess, c)
+	id, err := mgr.TimerSet("p_owner", "x", "", 0.1)
+	if err != nil {
+		t.Fatalf("TimerSet: %v", err)
+	}
+
+	mgr.onChildClosed("p_owner")
+
+	mgr.mu.Lock()
+	_, stillThere := mgr.timers[id]
+	mgr.mu.Unlock()
+	if stillThere {
+		t.Fatalf("delay timer was not removed when owner closed")
+	}
+	time.Sleep(200 * time.Millisecond) // past the original firesAt
+	if got := rec.snapshot(); len(got) != 0 {
+		t.Fatalf("delay timer fired after owner close: %+v", got)
+	}
+}
+
+// TestTimerCloseWatchedSubAgent is the exact shape of the reported
+// stale-fire bug: orchestrator registers a watcher on a sub-agent,
+// the sub-agent is closed, and the orchestrator must receive
+// nothing (no stale body delivered after close_process).
+func TestTimerCloseWatchedSubAgent(t *testing.T) {
+	sess, mgr, rec := newTestManager(t)
+	parent := fakeChild("p_owner")
+	sub := fakeChild("p_sub")
+	addChild(sess, parent)
+	addChild(sess, sub)
+	working := StateWorking
+	sub.idleState.Store(&working)
+
+	if _, err := mgr.TimerFireWhenIdleAny(
+		"p_owner",
+		"codex-review-591 finished. Read your own pane …",
+		"", []string{"p_sub"}, 0,
+	); err != nil {
+		t.Fatalf("TimerFireWhenIdleAny: %v", err)
+	}
+
+	mgr.onChildClosed("p_sub")
+
+	// Trailing classifier emission for the closed sub-agent must
+	// not deliver anything to the parent.
+	mgr.onChildStateChanged("p_sub", StateIdle)
+	if got := rec.snapshot(); len(got) != 0 {
+		t.Fatalf("stale fire delivered to parent after sub-agent close: %+v", got)
+	}
+}