Update PTY start call sites

The tab bar's row-2 summary was painted only for the active tab. Add a
per-child summaryTextFor/summaryRawFor helper (active variants now
delegate to it), carry each tab's childID on its tabRect, and loop over
all visible tabs so each renders its own summary under its column.
Layout is unchanged (still 3 rows); narrow tabs clip as before.

Resolves the per-tab summary TODO item.

.gitignore

@@ -7,4 +7,5 @@ spike-report-*.txt
 /bin/
 /spike
 /.worktrees/
+/.claude/worktrees/
 internal/harness/.artifacts/

CHANGELOG.md

@@ -6,6 +6,44 @@ loosely follows [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
 
 ## [Unreleased]
 
+### Added
+- MCP clients can now call `scratchpad_delete` with a scratchpad name
+  to remove a shared project scratchpad.
+
+### Changed
+- The tab bar now shows each visible agent tab's own summary instead
+  of only rendering the focused tab's summary.
+- Grid-mode `get_process_output` now returns whitespace-normalized
+  text to avoid sending padded terminal rows and repeated blank lines
+  over MCP.
+
+### Fixed
+- Injected agent input now sends the submit Enter as a separated,
+  settled keystroke so messages reliably submit instead of sometimes
+  sitting unsent in the composer.
+- Codex agents are no longer reported idle while a turn is still
+  running.
+- Slow MCP tool calls such as `wait_for_pattern` no longer block later
+  tool calls on the same MCP connection.
+- Closing an agent now escalates from SIGTERM to SIGKILL when needed,
+  so agents that ignore SIGTERM disappear from the running tab bar
+  after one Close action while keeping their exited pane readable.
+- Sidebar timer indicators now repaint as their visible countdown
+  value changes, so labels progress from minutes to seconds without
+  waiting for unrelated terminal output or focus changes.
+- Raw terminal focused actions now show a single `Close` row instead
+  of separate stop/delete-style lifecycle choices that did the same
+  thing for ephemeral terminal panes.
+- Restarting a process from the palette now restores the focused pane
+  and host chrome before waiting for the old process to exit, so the
+  tab bar and sidebar do not disappear during slow restarts.
+- Deleting the focused scratchpad now moves focus to another
+  scratchpad when one exists, or back to a running terminal/agent
+  instead of dropping into the empty state.
+- Multiline paste into raw terminal and command panes no longer pays
+  the agent-specific per-Enter delay, making large pasted input arrive
+  as one PTY write outside Claude/Codex/OpenCode panes.
+
 ## [0.0.7] - 2026-05-18
 
 ### Added

cmd/spike/main.go

@@ -108,7 +108,7 @@ func run(argv []string, cols, rows uint16, idleMS int, followHost, stdinPassthro
 	}
 	defer em.Close()
 
-	child, err := pty.Start(argv, nil, cols, rows)
+	child, err := pty.Start(argv, nil, "", cols, rows)
 	if err != nil {
 		return fmt.Errorf("pty: %w", err)
 	}

internal/app/app.go

@@ -161,6 +161,21 @@ func Run(ctx context.Context, opts Options) error {
 	// ctx is cancelled.
 	go sess.runClassifier(ctx)
 
+	core := &headlessCore{
+		projectDir:   opts.ProjectDir,
+		projectKey:   opts.ProjectKey,
+		presets:      presets,
+		settings:     appSettings,
+		pads:         pads,
+		trustStore:   trustStore,
+		persistStore: persistStore,
+		mcpSrv:       mcpSrv,
+		sess:         sess,
+		launcher:     launcher,
+		host:         host,
+	}
+	_ = core
+
 	st := &uiState{
 		sess:       sess,
 		presets:    presets,
@@ -171,6 +186,12 @@ func Run(ctx context.Context, opts Options) error {
 		timers:     host.timers,
 		hostCols:   cols,
 		hostRows:   rows,
+		view: ClientView{
+			ID:         "loopback",
+			ProjectKey: opts.ProjectKey,
+			Cols:       cols,
+			Rows:       rows,
+		},
 		stdinTTY:     term.IsTerminal(int(os.Stdin.Fd())),
 		metrics:      metrics,
 		settings:     appSettings,
@@ -252,6 +273,7 @@ func Run(ctx context.Context, opts Options) error {
 			}
 			st.dimsMu.Lock()
 			st.hostCols, st.hostRows = c, r
+			st.view.Resize(c, r)
 			l := st.layoutLocked()
 			st.dimsMu.Unlock()
 			st.mu.Lock()
@@ -326,6 +348,15 @@ func Run(ctx context.Context, opts Options) error {
 		}
 	}()
 
+	// Timer sidebar refresher: countdown labels are computed at draw
+	// time, so wake the sidebar when the next visible timer bucket is
+	// due to change even if no child PTY output arrives.
+	wg.Add(1)
+	go func() {
+		defer wg.Done()
+		st.runTimerSidebarRefresher(ctx)
+	}()
+
 	// Marquee ticker: while a focused sidebar row's name overflows the
 	// rail width, advance the pause-scroll-pause animation by marking
 	// the sidebar dirty every marqueeStep. The chrome ticker above does
@@ -399,6 +430,7 @@ type uiState struct {
 	outMu sync.Mutex
 
 	mu          sync.Mutex
+	view        ClientView
 	palette     *paletteState
 	focusedID   string
 	focusedName string
@@ -505,7 +537,14 @@ func (st *uiState) dbgf(format string, args ...any) {
 }
 
 func (st *uiState) activeSummaryText(width int) string {
-	text := st.activeSummaryRaw()
+	st.mu.Lock()
+	active := st.activeAgentID
+	st.mu.Unlock()
+	return st.summaryTextFor(active, width)
+}
+
+func (st *uiState) summaryTextFor(childID string, width int) string {
+	text := st.summaryRawFor(childID)
 	if text == "" || width <= 0 {
 		return ""
 	}
@@ -516,7 +555,14 @@ func (st *uiState) activeSummaryText(width int) string {
 }
 
 func (st *uiState) activeSummaryRaw() string {
-	if st.summaries == nil {
+	st.mu.Lock()
+	active := st.activeAgentID
+	st.mu.Unlock()
+	return st.summaryRawFor(active)
+}
+
+func (st *uiState) summaryRawFor(childID string) string {
+	if st.summaries == nil || childID == "" {
 		return ""
 	}
 	st.settingsMu.Lock()
@@ -525,13 +571,7 @@ func (st *uiState) activeSummaryRaw() string {
 	if !enabled {
 		return ""
 	}
-	st.mu.Lock()
+	sum := st.summaries.Summary(childID)
-	active := st.activeAgentID
-	st.mu.Unlock()
-	if active == "" {
-		return ""
-	}
-	sum := st.summaries.Summary(active)
 	text := strings.TrimSpace(sum.Text)
 	if text == "" {
 		return ""
@@ -557,6 +597,21 @@ func (st *uiState) promptTrust(processID, presetName, reason string) {
 	st.drawStatusLine()
 }
 
+func (st *uiState) focusChildLocked(c *Child) {
+	st.focusedPad = ""
+	st.focusedID = c.ID
+	st.focusedName = c.DisplayName()
+	st.view.FocusChild(c.ID)
+}
+
+func (st *uiState) focusPadLocked(name string) {
+	st.view.FocusPad(name)
+	st.focusedPad = st.view.FocusedPad
+	st.focusedID = st.view.FocusedID
+	st.padOffset = st.view.PadOffset
+	st.padOffsetName = st.view.PadOffsetName
+}
+
 // focusProcess is the SPEC §7 select_process hook. Routes through the
 // normal focus-change path; only takes effect if the process exists.
 func (st *uiState) focusProcess(processID string) {
@@ -569,9 +624,7 @@ func (st *uiState) focusProcess(processID string) {
 	onAlt := childIsOnAlt(c)
 	st.mu.Lock()
 	leavingPad := st.focusedPad != ""
-	st.focusedPad = ""
+	st.focusChildLocked(c)
-	st.focusedID = c.ID
-	st.focusedName = c.DisplayName()
 	st.updateActiveAgentLocked(c)
 	r := newViewportRenderer(layout)
 	r.SetChildOnAlt(onAlt)
@@ -634,12 +687,7 @@ func (st *uiState) focusScratchpad(name string) {
 	}
 	st.marquee.reset()
 	st.mu.Lock()
-	if st.padOffsetName != name {
+	st.focusPadLocked(name)
-		st.padOffset = 0
-		st.padOffsetName = name
-	}
-	st.focusedPad = name
-	st.focusedID = ""
 	st.focusedName = name
 	st.renderer = nil
 	st.mu.Unlock()
@@ -671,6 +719,20 @@ func (st *uiState) clearViewportArea() {
 	_, _ = os.Stdout.WriteString(b.String())
 }
 
+func (st *uiState) repaintFocusedWithChrome() {
+	st.mu.Lock()
+	padFocused := st.focusedPad != ""
+	st.mu.Unlock()
+	if padFocused {
+		st.repaintFocusedPad()
+	} else {
+		st.repaintFocused()
+	}
+	st.drawTabBar()
+	st.drawSidebar()
+	st.drawStatusLine()
+}
+
 func (st *uiState) restartFocusedCommand(processID string) {
 	c := st.sess.FindChild(processID)
 	if c == nil || c.Kind != KindCommand {
@@ -680,21 +742,24 @@ func (st *uiState) restartFocusedCommand(processID string) {
 	layout := st.layoutSnapshot()
 	renderer := newViewportRenderer(layout)
 	st.mu.Lock()
-	st.focusedID = c.ID
+	st.focusChildLocked(c)
-	st.focusedName = c.DisplayName()
 	st.renderer = renderer
 	st.repaintNextPTY = c.ID
 	st.repaintNextPTYBudget = 2
 	st.mu.Unlock()
 
-	st.outMu.Lock()
+	st.repaintFocusedWithChrome()
-	_, _ = os.Stdout.Write(renderer.ClearViewport())
-	st.outMu.Unlock()
 
 	if err := st.sess.Restart(c.ID, syscall.SIGTERM, layout.childCols(), layout.childRows()); err != nil {
 		st.flashError(fmt.Sprintf("restart %s: %v", c.DisplayName(), err))
+		st.drawTabBar()
+		st.drawSidebar()
+		st.drawStatusLine()
 		return
 	}
+	st.outMu.Lock()
+	_, _ = os.Stdout.Write(renderer.ClearViewport())
+	st.outMu.Unlock()
 	st.moveToViewportOrigin()
 	st.drawTabBar()
 	st.drawSidebar()
@@ -712,6 +777,7 @@ func (st *uiState) updateActiveAgentLocked(c *Child) {
 	}
 	if c.ParentID == "" {
 		st.activeAgentID = c.ID
+		st.view.ActiveAgentID = c.ID
 		return
 	}
 	// Walk up to the top-level agent.
@@ -725,6 +791,7 @@ func (st *uiState) updateActiveAgentLocked(c *Child) {
 	}
 	if root.Kind == KindAgent && root.ParentID == "" {
 		st.activeAgentID = root.ID
+		st.view.ActiveAgentID = root.ID
 	}
 }
 
@@ -741,12 +808,7 @@ func (st *uiState) notifyAttention(childID, reason string) {
 }
 
 func (st *uiState) scratchpadsChanged() {
-	st.padsCacheMu.Lock()
+	st.invalidateScratchpadsCache()
-	st.padsCache = nil
-	st.padsCacheMu.Unlock()
-	st.chromeCacheMu.Lock()
-	st.sidebarCache = ""
-	st.chromeCacheMu.Unlock()
 	st.drawSidebar()
 	st.mu.Lock()
 	focusedPad := st.focusedPad
@@ -756,6 +818,15 @@ func (st *uiState) scratchpadsChanged() {
 	}
 }
 
+func (st *uiState) invalidateScratchpadsCache() {
+	st.padsCacheMu.Lock()
+	st.padsCache = nil
+	st.padsCacheMu.Unlock()
+	st.chromeCacheMu.Lock()
+	st.sidebarCache = ""
+	st.chromeCacheMu.Unlock()
+}
+
 // OnChildSpawned auto-focuses the new child when the spawn came from
 // the user (palette, persistence restore, or an external MCP client with
 // no resolved identity). When ParentID is set — meaning a patterm-managed
@@ -783,9 +854,7 @@ func (st *uiState) OnChildSpawned(c *Child) {
 	layout := st.layoutSnapshot()
 	onAlt := childIsOnAlt(c)
 	st.mu.Lock()
-	st.focusedPad = ""
+	st.focusChildLocked(c)
-	st.focusedID = c.ID
-	st.focusedName = c.DisplayName()
 	st.updateActiveAgentLocked(c)
 	renderer := newViewportRenderer(layout)
 	renderer.SetChildOnAlt(onAlt)
@@ -860,10 +929,10 @@ func (st *uiState) OnChildExited(c *Child) {
 		if next == nil {
 			st.focusedID = ""
 			st.focusedName = ""
+			st.view.FocusedID = ""
 			renderEmpty = true
 		} else {
-			st.focusedID = next.ID
+			st.focusChildLocked(next)
-			st.focusedName = next.DisplayName()
 			st.updateActiveAgentLocked(next)
 			st.renderer = newViewportRenderer(layout)
 		}
@@ -872,6 +941,7 @@ func (st *uiState) OnChildExited(c *Child) {
 		// The active agent died; pin the agent tree to whatever agent
 		// root is still running, or clear it if none remain.
 		st.activeAgentID = firstRunningAgentID(st.sess.Children())
+		st.view.ActiveAgentID = st.activeAgentID
 	}
 	if st.palette != nil {
 		st.palette.children = st.sess.Children()
@@ -1143,6 +1213,55 @@ func (st *uiState) markSidebarDirty() {
 	}
 }
 
+func (st *uiState) runTimerSidebarRefresher(ctx context.Context) {
+	if st.timers == nil {
+		<-ctx.Done()
+		return
+	}
+	changes := st.timers.changeEvents()
+	var timer *time.Timer
+	var timerC <-chan time.Time
+	stop := func() {
+		if timer == nil {
+			return
+		}
+		if !timer.Stop() {
+			select {
+			case <-timer.C:
+			default:
+			}
+		}
+		timer = nil
+		timerC = nil
+	}
+	arm := func() {
+		stop()
+		wait, ok := st.timers.nextSidebarRefreshAfter(time.Now())
+		if !ok {
+			return
+		}
+		if wait < timerSidebarMinRefresh {
+			wait = timerSidebarMinRefresh
+		}
+		timer = time.NewTimer(wait)
+		timerC = timer.C
+	}
+	defer stop()
+	arm()
+	for {
+		select {
+		case <-ctx.Done():
+			return
+		case <-changes:
+			st.markSidebarDirty()
+			arm()
+		case <-timerC:
+			st.markSidebarDirty()
+			arm()
+		}
+	}
+}
+
 func (st *uiState) invalidateChromeCache() {
 	st.chromeCacheMu.Lock()
 	st.tabBarCache = ""
@@ -1299,7 +1418,10 @@ func (st *uiState) renderEmptyState() {
 func (st *uiState) hostSizeSnapshot() (uint16, uint16) {
 	st.dimsMu.Lock()
 	defer st.dimsMu.Unlock()
+	if st.view.Cols == 0 || st.view.Rows == 0 {
 		return st.hostCols, st.hostRows
+	}
+	return st.view.Cols, st.view.Rows
 }
 
 func (st *uiState) layoutSnapshot() terminalLayout {
@@ -1309,7 +1431,10 @@ func (st *uiState) layoutSnapshot() terminalLayout {
 }
 
 func (st *uiState) layoutLocked() terminalLayout {
+	if st.view.Cols == 0 || st.view.Rows == 0 {
 		return newTerminalLayout(st.hostCols, st.hostRows)
+	}
+	return newTerminalLayout(st.view.Cols, st.view.Rows)
 }
 
 // splitOnEnter walks input and returns each Enter byte (CR or LF) as
@@ -1433,9 +1558,10 @@ func (st *uiState) processStdin(chunk []byte) {
 		if st.focusedID != "" {
 			if c := st.sess.FindChild(st.focusedID); c != nil && c.Status() == StatusRunning {
 				prev := c.Owner()
-				// InjectAsUser splits Enter bytes onto their own
+				// Agent panes split Enter bytes onto their own writes
-				// writes so claude / codex / opencode don't treat a
+				// so claude / codex / opencode don't treat a
-				// "text\r" batch as a paste.
+				// "text\r" batch as a paste. Raw terminals keep paste
+				// bytes batched.
 				_ = c.InjectAsUser(forward)
 				if st.summaries != nil {
 					st.summaries.ObserveHumanInput(c.ID, forward)
@@ -1997,9 +2123,7 @@ func (st *uiState) closePalette(action paletteAction) {
 		layout := st.layoutSnapshot()
 		st.mu.Lock()
 		leavingPad := st.focusedPad != ""
-		st.focusedPad = ""
+		st.focusChildLocked(c)
-		st.focusedID = action.childID
-		st.focusedName = c.DisplayName()
 		st.updateActiveAgentLocked(c)
 		st.renderer = newViewportRenderer(layout)
 		st.mu.Unlock()
@@ -2131,20 +2255,45 @@ func (st *uiState) handlePadDelete(name string) {
 		st.repaintFocused()
 		return
 	}
+	st.mu.Lock()
+	wasFocused := st.focusedPad == name
+	st.mu.Unlock()
 	if err := st.pads.Delete(name); err != nil {
 		st.flashError(fmt.Sprintf("delete %s: %v", name, err))
 		return
 	}
+	if wasFocused {
+		st.invalidateScratchpadsCache()
+		if entries := st.padsList(); len(entries) > 0 {
+			next := entries[0].Name
 			st.mu.Lock()
-	if st.focusedPad == name {
+			st.focusPadLocked(next)
-		st.focusedPad = ""
+			st.focusedName = next
-	}
 			st.mu.Unlock()
-	st.scratchpadsChanged()
+			st.repaintFocusedWithChrome()
-	st.repaintFocused()
+			return
+		}
+		if next := firstRunningTopLevel(st.sess.Children()); next != nil {
+			st.focusProcess(next.ID)
+			return
+		}
+		st.mu.Lock()
+		st.focusedPad = ""
+		st.view.FocusedPad = ""
+		st.focusedName = ""
+		st.padOffset = 0
+		st.padOffsetName = ""
+		st.view.PadOffset = 0
+		st.view.PadOffsetName = ""
+		st.mu.Unlock()
+		st.renderEmptyState()
 		st.drawTabBar()
 		st.drawSidebar()
 		st.drawStatusLine()
+		return
+	}
+	st.scratchpadsChanged()
+	st.repaintFocusedWithChrome()
 }
 
 func (st *uiState) handlePadRename(oldName, newName string) {
@@ -2162,7 +2311,7 @@ func (st *uiState) handlePadRename(oldName, newName string) {
 	}
 	st.mu.Lock()
 	if st.focusedPad == oldName {
-		st.focusedPad = newName
+		st.focusPadLocked(newName)
 	}
 	st.mu.Unlock()
 	st.scratchpadsChanged()
@@ -2237,11 +2386,9 @@ func (st *uiState) handleChildRename(childID, newName string) {
 	st.drawStatusLine()
 }
 
-// handleChildClose removes a child entry entirely. For agents this is
+// handleChildClose removes a child entry entirely for process deletes.
-// equivalent to a SIGTERM kill (the entry is ephemeral and disappears
+// For agent Close, it terminates the PTY with escalation but preserves
-// from the session once the PTY exits). For command processes it's
+// the exited pane so the user can still read the corpse.
-// equivalent to the MCP close_process tool: SIGKILL if alive, then
-// drop the entry so it stops appearing in the switch/restart lists.
 func (st *uiState) handleChildClose(childID string, kill bool) {
 	if childID == "" {
 		st.repaintFocused()
@@ -2256,7 +2403,11 @@ func (st *uiState) handleChildClose(childID string, kill bool) {
 	if kill {
 		_ = st.sess.Close(childID, syscall.SIGKILL)
 	} else {
-		_ = st.sess.Kill(childID, syscall.SIGTERM)
+		go func() {
+			if err := st.sess.Terminate(childID, syscall.SIGTERM); err != nil {
+				logf("terminate child %s: %v", childID, err)
+			}
+		}()
 	}
 	st.repaintFocused()
 	st.drawTabBar()
@@ -2293,8 +2444,19 @@ func (st *uiState) handleProcRestart(childID string) {
 		return
 	}
 	layout := st.layoutSnapshot()
+	st.mu.Lock()
+	if c.ID == st.focusedID {
+		st.renderer = newViewportRenderer(layout)
+		st.repaintNextPTY = c.ID
+		st.repaintNextPTYBudget = 2
+	}
+	st.mu.Unlock()
+	st.repaintFocusedWithChrome()
 	if err := st.sess.Restart(childID, syscall.SIGTERM, layout.childCols(), layout.childRows()); err != nil {
 		st.flashError(fmt.Sprintf("restart %s: %v", c.DisplayName(), err))
+		st.drawTabBar()
+		st.drawSidebar()
+		st.drawStatusLine()
 		return
 	}
 	st.repaintFocused()
@@ -2420,6 +2582,7 @@ func (st *uiState) renderPadView(name, content string, layout terminalLayout) []
 		st.padOffset = 0
 	}
 	offset := st.padOffset
+	st.view.PadOffset = offset
 	st.mu.Unlock()
 
 	var b strings.Builder
@@ -2477,6 +2640,7 @@ func (st *uiState) exitPadView() {
 		return
 	}
 	st.focusedPad = ""
+	st.view.FocusedPad = ""
 	st.focusedName = ""
 	st.mu.Unlock()
 	st.clearViewportArea()
@@ -2503,6 +2667,7 @@ func (st *uiState) padScroll(delta int) {
 	if st.padOffset < 0 {
 		st.padOffset = 0
 	}
+	st.view.PadOffset = st.padOffset
 	st.mu.Unlock()
 	st.repaintFocusedPad()
 }

internal/app/child.go

@@ -26,6 +26,11 @@ import (
 // false positives (timestamps, exit codes, etc.).
 var portRegex = regexp.MustCompile(`https?://[^\s:/]+:(\d{2,5})(?:/[^\s]*)?`)
 
+const (
+	agentInterPieceDelay   = 15 * time.Millisecond
+	agentSubmitSettleDelay = 100 * time.Millisecond
+)
+
 type ChildStatus string
 
 const (
@@ -223,7 +228,7 @@ func (c *Child) startPTY(cols, rows uint16) (uint64, error) {
 	}
 	starting := StatusStarting
 	c.status.Store(&starting)
-	p, err := pkgpty.Start(c.Argv, c.Env, cols, rows)
+	p, err := pkgpty.Start(c.Argv, c.Env, c.WorkDir, cols, rows)
 	if err != nil {
 		em.Close()
 		errored := StatusErrored
@@ -625,25 +630,25 @@ func (c *Child) InjectAsOrchestrator(b []byte) error {
 }
 
 // writeInput is the shared PTY write path used by both injection
-// flavours. Each Enter byte (CR or LF) is split onto its own write
+// flavours. Agent panes split each Enter byte (CR or LF) onto its own
-// with a brief delay so TUI agents with paste-detection (claude,
+// write with a brief delay so TUI agents with paste-detection (claude,
 // codex, opencode) don't coalesce a trailing CR into the text that
-// preceded it. Without the split, `pty.Write([]byte("hello\r"))`
+// preceded it. Raw terminals and command panes receive the original
-// arrives at the agent as one read() and gets treated as multi-line
+// byte stream in one write; otherwise a multiline paste pays the agent
-// pasted content rather than "key Enter".
+// workaround's delay once per line.
 func (c *Child) writeInput(b []byte) error {
 	pty := c.PTY()
 	if pty == nil {
 		return errors.New("child has no pty")
 	}
-	pieces := splitOnEnter(b)
+	pieces := inputWritePieces(c.Kind, b)
 	if len(pieces) <= 1 {
 		_, err := pty.Write(b)
 		return err
 	}
 	for i, piece := range pieces {
-		if i > 0 {
+		if delay := pieceWriteDelay(i, len(pieces), piece); delay > 0 {
-			time.Sleep(15 * time.Millisecond)
+			time.Sleep(delay)
 		}
 		if _, err := pty.Write(piece); err != nil {
 			return err
@@ -652,6 +657,27 @@ func (c *Child) writeInput(b []byte) error {
 	return nil
 }
 
+func inputWritePieces(kind ChildKind, b []byte) [][]byte {
+	if kind != KindAgent {
+		return [][]byte{b}
+	}
+	return splitOnEnter(b)
+}
+
+func pieceWriteDelay(index, total int, piece []byte) time.Duration {
+	if index == 0 {
+		return 0
+	}
+	if index == total-1 && isLoneEnter(piece) {
+		return agentSubmitSettleDelay
+	}
+	return agentInterPieceDelay
+}
+
+func isLoneEnter(piece []byte) bool {
+	return len(piece) == 1 && (piece[0] == '\r' || piece[0] == '\n')
+}
+
 func mintIdentity() string {
 	var buf [12]byte
 	_, _ = rand.Read(buf[:])

internal/app/child_input_test.go

@@ -0,0 +1,90 @@
+package app
+
+import (
+	"bytes"
+	"testing"
+	"time"
+)
+
+func TestInputWritePiecesOnlySplitAgentEnters(t *testing.T) {
+	in := []byte("alpha\nbeta\rgamma")
+	for _, kind := range []ChildKind{KindTerminal, KindCommand} {
+		t.Run(string(kind), func(t *testing.T) {
+			got := inputWritePieces(kind, in)
+			if len(got) != 1 || !bytes.Equal(got[0], in) {
+				t.Fatalf("inputWritePieces(%s) = %#v, want one original chunk", kind, got)
+			}
+		})
+	}
+
+	got := inputWritePieces(KindAgent, in)
+	if len(got) != 5 {
+		t.Fatalf("agent pieces len = %d, want 5 (%#v)", len(got), got)
+	}
+	want := [][]byte{[]byte("alpha"), []byte("\n"), []byte("beta"), []byte("\r"), []byte("gamma")}
+	for i := range want {
+		if !bytes.Equal(got[i], want[i]) {
+			t.Fatalf("agent piece %d = %q, want %q", i, got[i], want[i])
+		}
+	}
+}
+
+func TestPieceWriteDelay(t *testing.T) {
+	cases := []struct {
+		name  string
+		index int
+		total int
+		piece []byte
+		want  time.Duration
+	}{
+		{
+			name:  "first piece",
+			index: 0,
+			total: 3,
+			piece: []byte("body"),
+			want:  0,
+		},
+		{
+			name:  "middle body piece",
+			index: 1,
+			total: 3,
+			piece: []byte("body"),
+			want:  agentInterPieceDelay,
+		},
+		{
+			name:  "final carriage return submit",
+			index: 1,
+			total: 2,
+			piece: []byte("\r"),
+			want:  agentSubmitSettleDelay,
+		},
+		{
+			name:  "final newline submit",
+			index: 1,
+			total: 2,
+			piece: []byte("\n"),
+			want:  agentSubmitSettleDelay,
+		},
+		{
+			name:  "final non-enter piece",
+			index: 2,
+			total: 3,
+			piece: []byte("tail"),
+			want:  agentInterPieceDelay,
+		},
+		{
+			name:  "standalone enter fast path",
+			index: 0,
+			total: 1,
+			piece: []byte("\r"),
+			want:  0,
+		},
+	}
+	for _, tc := range cases {
+		t.Run(tc.name, func(t *testing.T) {
+			if got := pieceWriteDelay(tc.index, tc.total, tc.piece); got != tc.want {
+				t.Fatalf("pieceWriteDelay(%d, %d, %q) = %s, want %s", tc.index, tc.total, tc.piece, got, tc.want)
+			}
+		})
+	}
+}

internal/app/chrome_model.go

@@ -0,0 +1,78 @@
+package app
+
+import "github.com/hjbdev/patterm/internal/scratchpad"
+
+// chromeModel is the semantic host chrome state. Renderers continue to own
+// ANSI output; this model is the serializable shape a client can draw locally.
+type chromeModel struct {
+	ProjectKey    string            `json:"project_key"`
+	FocusedID     string            `json:"focused_id,omitempty"`
+	FocusedPad    string            `json:"focused_pad,omitempty"`
+	ActiveAgentID string            `json:"active_agent_id,omitempty"`
+	Tabs          []childModel      `json:"tabs"`
+	Processes     []childModel      `json:"processes"`
+	AgentTree     []childModel      `json:"agent_tree"`
+	Sidebar       []navEntryModel   `json:"sidebar"`
+	Scratchpads   []scratchpadModel `json:"scratchpads"`
+}
+
+type childModel struct {
+	ID       string `json:"id"`
+	Name     string `json:"name"`
+	Kind     string `json:"kind"`
+	ParentID string `json:"parent_id,omitempty"`
+	Status   string `json:"status"`
+	Owner    string `json:"owner"`
+}
+
+type navEntryModel struct {
+	ChildID string `json:"child_id,omitempty"`
+	Pad     string `json:"pad,omitempty"`
+}
+
+type scratchpadModel struct {
+	Name string `json:"name"`
+}
+
+func buildChromeModel(projectKey string, view ClientView, children []*Child, pads []scratchpad.Entry) chromeModel {
+	active := view.ActiveAgentID
+	if active == "" {
+		active = activeRootID(children, view.FocusedID)
+	}
+	model := chromeModel{
+		ProjectKey:    projectKey,
+		FocusedID:     view.FocusedID,
+		FocusedPad:    view.FocusedPad,
+		ActiveAgentID: active,
+	}
+	for _, c := range runningTopLevels(children) {
+		model.Tabs = append(model.Tabs, serializeChildModel(c))
+	}
+	for _, c := range processList(children) {
+		model.Processes = append(model.Processes, serializeChildModel(c))
+	}
+	for _, c := range visibleAgentTree(children, active) {
+		model.AgentTree = append(model.AgentTree, serializeChildModel(c))
+	}
+	for _, n := range sidebarNav(children, active, pads) {
+		model.Sidebar = append(model.Sidebar, navEntryModel{ChildID: n.childID, Pad: n.pad})
+	}
+	for _, p := range pads {
+		model.Scratchpads = append(model.Scratchpads, scratchpadModel{Name: p.Name})
+	}
+	return model
+}
+
+func serializeChildModel(c *Child) childModel {
+	if c == nil {
+		return childModel{}
+	}
+	return childModel{
+		ID:       c.ID,
+		Name:     c.DisplayName(),
+		Kind:     string(c.Kind),
+		ParentID: c.ParentID,
+		Status:   string(c.Status()),
+		Owner:    string(c.Owner()),
+	}
+}

internal/app/chrome_model_test.go

@@ -0,0 +1,24 @@
+package app
+
+import "testing"
+
+func TestBuildChromeModelSeparatesProcessesTabsAndSidebar(t *testing.T) {
+	running := StatusRunning
+	proc := testProcess("p1", "server", running)
+	agent := testAgent("a1", "codex", "", running)
+	sub := testAgent("a2", "worker", "a1", running)
+
+	model := buildChromeModel("project", ClientView{FocusedID: "p1", ActiveAgentID: "a1"}, []*Child{proc, agent, sub}, nil)
+	if len(model.Tabs) != 1 || model.Tabs[0].ID != "a1" {
+		t.Fatalf("tabs = %#v, want only top-level agent", model.Tabs)
+	}
+	if len(model.Processes) != 1 || model.Processes[0].ID != "p1" {
+		t.Fatalf("processes = %#v, want process section", model.Processes)
+	}
+	if len(model.AgentTree) != 2 || model.AgentTree[0].ID != "a1" || model.AgentTree[1].ID != "a2" {
+		t.Fatalf("agent tree = %#v", model.AgentTree)
+	}
+	if len(model.Sidebar) != 3 || model.Sidebar[0].ChildID != "p1" || model.Sidebar[1].ChildID != "a1" {
+		t.Fatalf("sidebar = %#v", model.Sidebar)
+	}
+}

internal/app/client_subscriber.go

@@ -0,0 +1,122 @@
+package app
+
+import (
+	"encoding/json"
+	"sync"
+
+	"github.com/hjbdev/patterm/internal/protocol"
+)
+
+const defaultClientSubscriberQueue = 256
+
+// clientSubscriber is the daemon-to-client event bridge. Unlike daemon-local
+// listeners such as timers, debug capture, and waiters, it never blocks the PTY
+// pump: PTY chunks are copied before enqueue, and overflow marks the pane as
+// needing a fresh snapshot.
+type clientSubscriber struct {
+	projectKey string
+	frames     chan protocol.Frame
+
+	mu               sync.Mutex
+	snapshotRequired map[string]bool
+	lifecycleDirty   bool
+}
+
+func newClientSubscriber(projectKey string, size int) *clientSubscriber {
+	if size <= 0 {
+		size = defaultClientSubscriberQueue
+	}
+	return &clientSubscriber{
+		projectKey:       projectKey,
+		frames:           make(chan protocol.Frame, size),
+		snapshotRequired: make(map[string]bool),
+		lifecycleDirty:   false,
+	}
+}
+
+func (s *clientSubscriber) Recv() (protocol.Frame, bool) {
+	f, ok := <-s.frames
+	return f, ok
+}
+
+func (s *clientSubscriber) SnapshotRequired(childID string) bool {
+	s.mu.Lock()
+	defer s.mu.Unlock()
+	return s.snapshotRequired[childID]
+}
+
+func (s *clientSubscriber) OnChildSpawned(c *Child) {
+	s.sendLifecycle(protocol.LifecycleSpawned, c, "")
+}
+
+func (s *clientSubscriber) OnChildExited(c *Child) {
+	s.sendLifecycle(protocol.LifecycleExited, c, "")
+}
+
+func (s *clientSubscriber) OnChildClosed(id string) {
+	s.sendFrame(protocol.Frame{Type: protocol.FrameLifecycle, Payload: mustJSON(protocol.Lifecycle{
+		Kind:       protocol.LifecycleClosed,
+		ProjectKey: s.projectKey,
+		ChildID:    id,
+	})})
+}
+
+func (s *clientSubscriber) OnChildStateChanged(id string, state IdleState) {
+	s.sendFrame(protocol.Frame{Type: protocol.FrameLifecycle, Payload: mustJSON(protocol.Lifecycle{
+		Kind:       protocol.LifecycleStateChanged,
+		ProjectKey: s.projectKey,
+		ChildID:    id,
+		State:      string(state),
+	})})
+}
+
+func (s *clientSubscriber) OnPTYOut(childID string, chunk []byte) {
+	cp := append([]byte(nil), chunk...)
+	f, err := protocol.NewFrame(protocol.FramePaneChunk, protocol.PaneChunk{PaneID: childID, Bytes: cp})
+	if err != nil {
+		return
+	}
+	select {
+	case s.frames <- f:
+	default:
+		s.mu.Lock()
+		s.snapshotRequired[childID] = true
+		s.mu.Unlock()
+	}
+}
+
+func (s *clientSubscriber) sendLifecycle(kind protocol.LifecycleKind, c *Child, state string) {
+	var child json.RawMessage
+	if c != nil {
+		child = mustJSON(serializeChildModel(c))
+	}
+	childID := ""
+	if c != nil {
+		childID = c.ID
+	}
+	s.sendFrame(protocol.Frame{Type: protocol.FrameLifecycle, Payload: mustJSON(protocol.Lifecycle{
+		Kind:       kind,
+		ProjectKey: s.projectKey,
+		ChildID:    childID,
+		Child:      child,
+		State:      state,
+	})})
+}
+
+func (s *clientSubscriber) sendFrame(f protocol.Frame) {
+	select {
+	case s.frames <- f:
+	default:
+		s.mu.Lock()
+		s.lifecycleDirty = true
+		s.mu.Unlock()
+	}
+}
+
+func mustJSON(v any) json.RawMessage {
+	b, err := json.Marshal(v)
+	if err != nil {
+		return nil
+	}
+	return b
+}

internal/app/client_subscriber_test.go

@@ -0,0 +1,32 @@
+package app
+
+import (
+	"testing"
+
+	"github.com/hjbdev/patterm/internal/protocol"
+)
+
+func TestClientSubscriberCopiesChunksAndMarksSnapshotOnOverflow(t *testing.T) {
+	sub := newClientSubscriber("project", 1)
+	chunk := []byte("first")
+	sub.OnPTYOut("p_123456", chunk)
+	chunk[0] = 'X'
+
+	f, ok := sub.Recv()
+	if !ok {
+		t.Fatalf("Recv closed")
+	}
+	payload, err := protocol.Decode[protocol.PaneChunk](f)
+	if err != nil {
+		t.Fatalf("Decode: %v", err)
+	}
+	if string(payload.Bytes) != "first" {
+		t.Fatalf("payload retained pump buffer: %q", string(payload.Bytes))
+	}
+
+	sub.OnPTYOut("p_123456", []byte("queued"))
+	sub.OnPTYOut("p_123456", []byte("dropped"))
+	if !sub.SnapshotRequired("p_123456") {
+		t.Fatalf("overflow did not mark pane snapshot required")
+	}
+}

internal/app/client_view.go

@@ -0,0 +1,39 @@
+package app
+
+// ClientView is the per-client UI cursor over daemon-owned project/process
+// state. In loopback mode there is one view, owned by uiState; future network
+// clients will each get their own copy.
+type ClientView struct {
+	ID            string
+	ProjectKey    string
+	FocusedID     string
+	FocusedPad    string
+	ActiveAgentID string
+	PadOffset     int
+	PadOffsetName string
+	Cols          uint16
+	Rows          uint16
+}
+
+func (v *ClientView) FocusChild(id string) {
+	v.FocusedID = id
+	v.FocusedPad = ""
+}
+
+func (v *ClientView) FocusPad(name string) {
+	v.FocusedID = ""
+	v.FocusedPad = name
+	if v.PadOffsetName != name {
+		v.PadOffset = 0
+		v.PadOffsetName = name
+	}
+}
+
+func (v *ClientView) ClearPadFocus() {
+	v.FocusedPad = ""
+}
+
+func (v *ClientView) Resize(cols, rows uint16) {
+	v.Cols = cols
+	v.Rows = rows
+}

internal/app/daemon_core.go

@@ -0,0 +1,29 @@
+package app
+
+import (
+	"github.com/hjbdev/patterm/internal/mcp"
+	"github.com/hjbdev/patterm/internal/persist"
+	"github.com/hjbdev/patterm/internal/preset"
+	"github.com/hjbdev/patterm/internal/scratchpad"
+	"github.com/hjbdev/patterm/internal/trust"
+)
+
+// headlessCore is the daemon-owned half of today's single-process app. It is
+// intentionally small for the foundation phase: it groups process/project
+// state while the existing loopback client still renders in-process.
+type headlessCore struct {
+	projectDir string
+	projectKey string
+
+	presets  preset.Set
+	settings settings
+
+	pads         *scratchpad.Store
+	trustStore   *trust.Store
+	persistStore *persist.Store
+
+	mcpSrv   *mcp.Server
+	sess     *Session
+	launcher *Launcher
+	host     *toolHost
+}

internal/app/host.go

@@ -7,6 +7,7 @@ import (
 	"sync"
 	"syscall"
 	"time"
+	"unicode"
 
 	"github.com/hjbdev/patterm/internal/mcp"
 	"github.com/hjbdev/patterm/internal/preset"
@@ -398,7 +399,7 @@ func (h *toolHost) GetProcessOutput(callerID, processID, mode string, sinceOffse
 		if c.Kind == KindAgent {
 			txt = applyChromeTrim(txt, h.chromeHintsFor(c.PresetRef))
 		}
-		out.Content = txt
+		out.Content = normalizeGridText(txt)
 		return out, nil
 	case "stream":
 		b, end := c.StreamRead(sinceOffset)
@@ -832,6 +833,14 @@ func (h *toolHost) ScratchpadAppend(name, content string) error {
 	return err
 }
 
+func (h *toolHost) ScratchpadDelete(name string) error {
+	err := h.pads.Delete(name)
+	if err == nil && h.scratch != nil {
+		h.scratch.scratchpadsChanged()
+	}
+	return err
+}
+
 func (h *toolHost) WhoAmI(callerID string) mcp.WhoAmI {
 	w := mcp.WhoAmI{
 		ProcessID: callerID,
@@ -1010,6 +1019,30 @@ func stripANSI(s string) string {
 	return ansiRegexp.ReplaceAllString(s, "")
 }
 
+func normalizeGridText(s string) string {
+	s = strings.ReplaceAll(s, "\r\n", "\n")
+	s = strings.ReplaceAll(s, "\r", "\n")
+
+	lines := strings.Split(s, "\n")
+	out := make([]string, 0, len(lines))
+	pendingBlank := false
+	for _, line := range lines {
+		line = strings.TrimRightFunc(line, unicode.IsSpace)
+		if line == "" {
+			if len(out) > 0 {
+				pendingBlank = true
+			}
+			continue
+		}
+		if pendingBlank {
+			out = append(out, "")
+			pendingBlank = false
+		}
+		out = append(out, line)
+	}
+	return strings.Join(out, "\n")
+}
+
 // stripANSIBytes is the byte-slice form of stripANSI. Skips the
 // string conversion and the regex DFA — useful when the caller will
 // itself walk the result line-by-line (SearchOutput) or feed it to a
@@ -1091,7 +1124,7 @@ func availableToolsForRole(role mcp.CallerRole) []string {
 		"send_input", "send_message", "request_human_attention",
 		"timer_wait", "timer_set", "timer_fire_when_idle_any", "timer_fire_when_idle_all",
 		"timer_cancel", "timer_pause", "timer_resume", "timer_list",
-		"scratchpad_list", "scratchpad_read", "scratchpad_write", "scratchpad_append",
+		"scratchpad_list", "scratchpad_read", "scratchpad_write", "scratchpad_append", "scratchpad_delete",
 		"whoami", "help",
 	}
 	if role == mcp.RoleOrchestrator {
@@ -1146,8 +1179,8 @@ func helpFor(topic string) mcp.HelpResponse {
 	case "scratchpads":
 		return mcp.HelpResponse{
 			Topic:        "scratchpads",
-			Content:      "Project-scoped markdown files. Read returns content + revision; pass that back as expected_revision on write to get last-write-wins-with-detection. Append is unconditional.",
+			Content:      "Project-scoped markdown files. Read returns content + revision; pass that back as expected_revision on write to get last-write-wins-with-detection. Append is unconditional; delete removes a pad by name.",
-			RelatedTools: []string{"scratchpad_list", "scratchpad_read", "scratchpad_write", "scratchpad_append"},
+			RelatedTools: []string{"scratchpad_list", "scratchpad_read", "scratchpad_write", "scratchpad_append", "scratchpad_delete"},
 		}
 	case "timers":
 		return mcp.HelpResponse{

internal/app/idle_test.go

@@ -57,6 +57,21 @@ func TestClassifyTitleStability(t *testing.T) {
 	}
 }
 
+func TestClassifyTitleStabilityThinkingPatternOverridesIdle(t *testing.T) {
+	cfg := &resolvedIdleDetection{
+		strategy:        StrategyOSCTitleStability,
+		idleThresholdMS: 2000,
+		thinkingRegexes: []*regexp.Regexp{mustCompile(t, `(?i)esc to interrupt`)},
+	}
+	screen := []byte("• Working (5s • esc to interrupt)")
+	if got, _ := classify(cfg, false, false, 9999, 5000, "codex", nil, screen); got != StateThinking {
+		t.Fatalf("thinking screen marker: got %q want %q", got, StateThinking)
+	}
+	if got, _ := classify(cfg, false, false, 9999, 5000, "codex", nil, []byte(">_")); got != StateIdle {
+		t.Fatalf("stable title without marker: got %q want %q", got, StateIdle)
+	}
+}
+
 func TestClassifyTitleStatus(t *testing.T) {
 	cfg := &resolvedIdleDetection{
 		strategy:        StrategyOSCTitleStatus,

internal/app/palette.go

@@ -267,9 +267,18 @@ func (p *paletteState) buildItems(macro string) []paletteItem {
 				out = append(out,
 					paletteItem{label: "Rename", hint: "rename agent · " + name,
 						action: paletteAction{kind: "agent-rename-form", childID: c.ID}, group: groupFocused},
-					paletteItem{label: "Close", hint: "close agent · " + name + " (SIGTERM)",
+					paletteItem{label: "Close", hint: "close agent · " + name + " (SIGTERM, escalates)",
 						action: paletteAction{kind: "agent-close", childID: c.ID}, group: groupFocused},
 				)
+			case KindTerminal:
+				out = append(out,
+					paletteItem{label: "Rename", hint: "rename terminal · " + name,
+						action: paletteAction{kind: "proc-rename-form", childID: c.ID}, group: groupFocused},
+					paletteItem{label: "Close", hint: "close terminal · " + name + " (SIGTERM)",
+						action: paletteAction{kind: "proc-stop", childID: c.ID}, group: groupFocused},
+					paletteItem{label: "Restart", hint: "restart terminal · " + name,
+						action: paletteAction{kind: "proc-restart", childID: c.ID}, group: groupFocused},
+				)
 			default:
 				out = append(out,
 					paletteItem{label: "Rename", hint: "rename process · " + name,

internal/app/palette_context_test.go

@@ -83,6 +83,25 @@ func TestContextItemsProcess(t *testing.T) {
 	}
 }
 
+func TestContextItemsTerminalUsesCloseNotStop(t *testing.T) {
+	c := makeFakeChild("tid", "terminal", KindTerminal)
+	p := newPalette([]*Child{c}, "tid", "", preset.Set{})
+	if _, it := findItem(p, "proc-stop"); it == nil || it.label != "Close" {
+		t.Fatalf("terminal close row missing or mislabelled: %+v", it)
+	}
+	if _, it := findItem(p, "proc-restart"); it == nil {
+		t.Fatalf("terminal restart row missing")
+	}
+	if i, _ := findItem(p, "proc-delete"); i != -1 {
+		t.Fatalf("terminal should not show a separate delete/close row, found at %d", i)
+	}
+	for i, it := range p.items {
+		if it.label == "Stop" {
+			t.Fatalf("terminal should not show Stop row, found at %d", i)
+		}
+	}
+}
+
 func TestContextItemsAppearAboveSwitch(t *testing.T) {
 	// Two children so there's still a non-focused switch entry to compare
 	// against (the focused child is suppressed from the Open section).

internal/app/ring_test.go

@@ -104,3 +104,44 @@ func TestStripANSIBytesEquivalence(t *testing.T) {
 		}
 	}
 }
+
+func TestNormalizeGridText(t *testing.T) {
+	cases := []struct {
+		name string
+		in   string
+		want string
+	}{
+		{
+			name: "line endings",
+			in:   "one\r\ntwo\rthree",
+			want: "one\ntwo\nthree",
+		},
+		{
+			name: "trailing whitespace",
+			in:   "one   \ntwo\t\t\nthree",
+			want: "one\ntwo\nthree",
+		},
+		{
+			name: "collapse blank runs",
+			in:   "one\n\n\n two\n \n\t\nthree",
+			want: "one\n\n two\n\nthree",
+		},
+		{
+			name: "trim leading and trailing blanks",
+			in:   "\n \n\t\none\n\n",
+			want: "one",
+		},
+		{
+			name: "already clean",
+			in:   "one\n\ntwo\nthree",
+			want: "one\n\ntwo\nthree",
+		},
+	}
+	for _, tc := range cases {
+		t.Run(tc.name, func(t *testing.T) {
+			if got := normalizeGridText(tc.in); got != tc.want {
+				t.Fatalf("normalizeGridText(%q) = %q, want %q", tc.in, got, tc.want)
+			}
+		})
+	}
+}

internal/app/scratchpad_delete_test.go

@@ -0,0 +1,137 @@
+package app
+
+import (
+	"errors"
+	"io"
+	"os"
+	"testing"
+
+	"github.com/hjbdev/patterm/internal/preset"
+	"github.com/hjbdev/patterm/internal/scratchpad"
+)
+
+func silenceStdout(t *testing.T) {
+	t.Helper()
+	old := os.Stdout
+	r, w, err := os.Pipe()
+	if err != nil {
+		t.Fatalf("pipe stdout: %v", err)
+	}
+	done := make(chan struct{})
+	go func() {
+		_, _ = io.Copy(io.Discard, r)
+		close(done)
+	}()
+	os.Stdout = w
+	t.Cleanup(func() {
+		os.Stdout = old
+		_ = w.Close()
+		<-done
+		_ = r.Close()
+	})
+}
+
+func newScratchpadDeleteTestState(t *testing.T) (*uiState, *scratchpad.Store) {
+	t.Helper()
+	t.Setenv("XDG_DATA_HOME", t.TempDir())
+	pads, err := scratchpad.Open("scratchpad-delete-test")
+	if err != nil {
+		t.Fatalf("scratchpad.Open: %v", err)
+	}
+	sess := NewSession(t.TempDir(), "scratchpad-delete-test")
+	t.Cleanup(sess.Shutdown)
+	st := &uiState{
+		sess:       sess,
+		pads:       pads,
+		hostCols:   120,
+		hostRows:   40,
+		chromeWake: make(chan struct{}, 1),
+	}
+	return st, pads
+}
+
+func TestDeletingFocusedScratchpadFocusesAnotherPad(t *testing.T) {
+	silenceStdout(t)
+	st, pads := newScratchpadDeleteTestState(t)
+	if _, err := pads.Write("alpha.md", "alpha", ""); err != nil {
+		t.Fatalf("write alpha: %v", err)
+	}
+	if _, err := pads.Write("beta.md", "beta", ""); err != nil {
+		t.Fatalf("write beta: %v", err)
+	}
+	st.focusedPad = "alpha.md"
+	st.focusedName = "alpha.md"
+	st.padOffsetName = "alpha.md"
+	st.padOffset = 3
+
+	st.handlePadDelete("alpha.md")
+
+	if st.focusedPad != "beta.md" {
+		t.Fatalf("focusedPad = %q, want beta.md", st.focusedPad)
+	}
+	if st.focusedID != "" {
+		t.Fatalf("focusedID = %q, want empty while another pad is focused", st.focusedID)
+	}
+	if st.padOffset != 0 || st.padOffsetName != "beta.md" {
+		t.Fatalf("pad offset = (%q,%d), want (beta.md,0)", st.padOffsetName, st.padOffset)
+	}
+}
+
+func TestDeletingLastFocusedScratchpadFocusesRunningChild(t *testing.T) {
+	silenceStdout(t)
+	st, pads := newScratchpadDeleteTestState(t)
+	if _, err := pads.Write("only.md", "only", ""); err != nil {
+		t.Fatalf("write only: %v", err)
+	}
+	child := makeFakeChild("pid", "devserver", KindCommand)
+	addChild(st.sess, child)
+	st.focusedPad = "only.md"
+	st.focusedName = "only.md"
+
+	st.handlePadDelete("only.md")
+
+	if st.focusedPad != "" {
+		t.Fatalf("focusedPad = %q, want empty after falling back to child", st.focusedPad)
+	}
+	if st.focusedID != "pid" {
+		t.Fatalf("focusedID = %q, want pid", st.focusedID)
+	}
+}
+
+type scratchpadChangeRecorder struct {
+	count int
+}
+
+func (r *scratchpadChangeRecorder) scratchpadsChanged() {
+	r.count++
+}
+
+func TestToolHostScratchpadDeleteRemovesPadAndRefreshes(t *testing.T) {
+	t.Setenv("XDG_DATA_HOME", t.TempDir())
+	pads, err := scratchpad.Open("scratchpad-delete-host-test")
+	if err != nil {
+		t.Fatalf("scratchpad.Open: %v", err)
+	}
+	if _, err := pads.Write("doomed.md", "content", ""); err != nil {
+		t.Fatalf("write doomed.md: %v", err)
+	}
+	recorder := &scratchpadChangeRecorder{}
+	host := newToolHost(nil, pads, nil, preset.Set{}, nil, 120, 40)
+	host.scratch = recorder
+
+	if err := host.ScratchpadDelete("doomed.md"); err != nil {
+		t.Fatalf("ScratchpadDelete: %v", err)
+	}
+	if recorder.count != 1 {
+		t.Fatalf("scratchpadsChanged calls = %d, want 1", recorder.count)
+	}
+	if _, _, err := pads.Read("doomed.md"); !errors.Is(err, os.ErrNotExist) {
+		t.Fatalf("read deleted pad error = %v, want os.ErrNotExist", err)
+	}
+	if err := host.ScratchpadDelete("doomed.md"); !errors.Is(err, os.ErrNotExist) {
+		t.Fatalf("delete missing error = %v, want os.ErrNotExist", err)
+	}
+	if recorder.count != 1 {
+		t.Fatalf("scratchpadsChanged calls after failed delete = %d, want 1", recorder.count)
+	}
+}

internal/app/session.go

@@ -46,6 +46,13 @@ type Session struct {
 	listenersMu sync.Mutex
 	listeners   atomic.Pointer[[]ChildEventListener]
 
+	// clientListeners is the network-client subscriber path. These
+	// listeners must be non-blocking and copy PTY chunks before enqueueing;
+	// daemon-internal observers (timers, debug capture, waiters) stay on
+	// listeners above so backpressure policy is isolated to clients.
+	clientListenersMu sync.Mutex
+	clientListeners   atomic.Pointer[[]ChildEventListener]
+
 	// persistStore records top-level command entries to a per-project
 	// JSON file so they can be re-spawned after patterm restarts.
 	// Optional; nil means "no persistence" (used by unit tests).
@@ -118,6 +125,16 @@ func (s *Session) Subscribe(l ChildEventListener) {
 	s.listeners.Store(&next)
 }
 
+func (s *Session) SubscribeClient(l ChildEventListener) {
+	s.clientListenersMu.Lock()
+	defer s.clientListenersMu.Unlock()
+	prev := s.clientListenersSnapshot()
+	next := make([]ChildEventListener, 0, len(prev)+1)
+	next = append(next, prev...)
+	next = append(next, l)
+	s.clientListeners.Store(&next)
+}
+
 // Unsubscribe removes a previously-registered listener. Safe to call
 // with a listener that wasn't registered (no-op).
 func (s *Session) Unsubscribe(l ChildEventListener) {
@@ -146,16 +163,30 @@ func (s *Session) listenersSnapshot() []ChildEventListener {
 	return *p
 }
 
+func (s *Session) clientListenersSnapshot() []ChildEventListener {
+	p := s.clientListeners.Load()
+	if p == nil {
+		return nil
+	}
+	return *p
+}
+
 func (s *Session) emitSpawn(c *Child) {
 	for _, l := range s.listenersSnapshot() {
 		l.OnChildSpawned(c)
 	}
+	for _, l := range s.clientListenersSnapshot() {
+		l.OnChildSpawned(c)
+	}
 }
 
 func (s *Session) emitExit(c *Child) {
 	for _, l := range s.listenersSnapshot() {
 		l.OnChildExited(c)
 	}
+	for _, l := range s.clientListenersSnapshot() {
+		l.OnChildExited(c)
+	}
 }
 
 // emitPTYOut dispatches a fresh PTY chunk to every listener. Listeners
@@ -165,18 +196,27 @@ func (s *Session) emitPTYOut(id string, chunk []byte) {
 	for _, l := range s.listenersSnapshot() {
 		l.OnPTYOut(id, chunk)
 	}
+	for _, l := range s.clientListenersSnapshot() {
+		l.OnPTYOut(id, chunk)
+	}
 }
 
 func (s *Session) emitStateChanged(id string, state IdleState) {
 	for _, l := range s.listenersSnapshot() {
 		l.OnChildStateChanged(id, state)
 	}
+	for _, l := range s.clientListenersSnapshot() {
+		l.OnChildStateChanged(id, state)
+	}
 }
 
 func (s *Session) emitClosed(id string) {
 	for _, l := range s.listenersSnapshot() {
 		l.OnChildClosed(id)
 	}
+	for _, l := range s.clientListenersSnapshot() {
+		l.OnChildClosed(id)
+	}
 }
 
 func (s *Session) ChildEnv() []string {
@@ -395,6 +435,20 @@ func (s *Session) Close(id string, sig syscall.Signal) error {
 	return nil
 }
 
+// Terminate stops a live child with SIGTERM/SIGKILL escalation but
+// leaves its session entry intact so callers can keep showing the
+// exited pane.
+func (s *Session) Terminate(id string, sig syscall.Signal) error {
+	c := s.FindChild(id)
+	if c == nil {
+		return fmt.Errorf("no such process %q", id)
+	}
+	if c.IsLive() {
+		terminateAndWait(c, sig, childStopTimeout)
+	}
+	return nil
+}
+
 // mintUniqueIDLocked mints an opaque process_id (SPEC §7) and retries
 // if it collides with an existing entry. Caller holds s.mu.
 func (s *Session) mintUniqueIDLocked() string {

internal/app/session_test.go

@@ -1,6 +1,7 @@
 package app
 
 import (
+	"strings"
 	"syscall"
 	"testing"
 	"time"
@@ -101,6 +102,50 @@ func TestSpawnInstallsIdleDetectionBeforePublish(t *testing.T) {
 	}
 }
 
+func TestTerminateEscalatesWithoutRemovingEntry(t *testing.T) {
+	sess := NewSession(t.TempDir(), "test")
+	c, err := sess.Spawn(SpawnSpec{
+		Kind: KindAgent,
+		Argv: []string{"sh", "-c", "trap '' TERM; echo ready; while :; do sleep 1; done"},
+	}, 80, 24)
+	if err != nil {
+		t.Fatalf("spawn: %v", err)
+	}
+	t.Cleanup(func() {
+		if c.IsLive() {
+			_ = c.signal(syscall.SIGKILL)
+		}
+	})
+	waitUntilLive(t, c)
+	waitForStreamText(t, c, "ready")
+
+	start := time.Now()
+	if err := sess.Terminate(c.ID, syscall.SIGTERM); err != nil {
+		t.Fatalf("Terminate: %v", err)
+	}
+	if elapsed := time.Since(start); elapsed < childStopTimeout {
+		t.Fatalf("Terminate returned before SIGKILL fallback: elapsed=%s timeout=%s", elapsed, childStopTimeout)
+	}
+	waitUntilNotLive(t, c)
+
+	if got := sess.FindChild(c.ID); got == nil {
+		t.Fatalf("Terminate removed child entry %s", c.ID)
+	}
+}
+
+func waitForStreamText(t *testing.T, c *Child, want string) {
+	t.Helper()
+	deadline := time.Now().Add(5 * time.Second)
+	for time.Now().Before(deadline) {
+		b, _ := c.StreamRead(0)
+		if strings.Contains(string(b), want) {
+			return
+		}
+		time.Sleep(20 * time.Millisecond)
+	}
+	t.Fatalf("child %s never wrote %q", c.ID, want)
+}
+
 func waitUntilLive(t *testing.T, c *Child) {
 	t.Helper()
 	deadline := time.Now().Add(5 * time.Second)

internal/app/summarizer_test.go

@@ -52,6 +52,41 @@ func TestWrapSidebarSummaryKeepsWordBoundaries(t *testing.T) {
 	}
 }
 
+func TestSummaryTextForSelectsChildAndClips(t *testing.T) {
+	sess := NewSession(t.TempDir(), "test")
+	cfg := defaultSettings()
+	st := &uiState{
+		sess:     sess,
+		settings: cfg,
+		summaries: newSummaryManager(sess, t.TempDir(), preset.Set{}, func() autoSummarySettings {
+			return cfg.AutoSummary.clone()
+		}, nil, nil),
+	}
+	st.summaries.mu.Lock()
+	st.summaries.entries["a1"] = &summaryEntry{state: summaryState{Text: " alpha summary "}}
+	st.summaries.entries["a2"] = &summaryEntry{state: summaryState{Text: "beta summary"}}
+	st.summaries.entries["empty"] = &summaryEntry{state: summaryState{Text: "   "}}
+	st.summaries.entries["long"] = &summaryEntry{state: summaryState{Text: "abcdefghijklmnopqrstuvwxyz"}}
+	st.summaries.mu.Unlock()
+
+	if got := st.summaryTextFor("a2", 20); got != "beta summary" {
+		t.Fatalf("summaryTextFor(a2) = %q, want beta summary", got)
+	}
+	if got := st.summaryTextFor("empty", 20); got != "" {
+		t.Fatalf("summaryTextFor(empty) = %q, want empty", got)
+	}
+	if got := st.summaryTextFor("long", 8); got != "abcdefg…" {
+		t.Fatalf("summaryTextFor(long) = %q, want abcdefg…", got)
+	}
+
+	st.settingsMu.Lock()
+	st.settings.AutoSummary.Enabled = false
+	st.settingsMu.Unlock()
+	if got := st.summaryTextFor("a1", 20); got != "" {
+		t.Fatalf("summaryTextFor disabled = %q, want empty", got)
+	}
+}
+
 func TestSummaryManagerArmsOnlyTrackedTopLevelAgents(t *testing.T) {
 	sess := NewSession(t.TempDir(), "test")
 	c := newChildEntry("a1", "agent", KindAgent, []string{"fake"}, nil, "", "", "")

internal/app/tabbar.go

@@ -59,6 +59,7 @@ func (st *uiState) drawTabBar() {
 	newHintW := utf8.RuneCountInString(newHint) + 2 // " + new " framing
 
 	type tabRect struct {
+		childID    string
 		startCol   int
 		width      int
 		label      string
@@ -66,8 +67,6 @@ func (st *uiState) drawTabBar() {
 		glyphStyle string
 		active     bool
 	}
-	activeTab := -1
-
 	// Reserve space at the right edge for "+ new". If there are too
 	// many tabs to fit even at minTabWidth, drop tabs from the right
 	// until they do. The current focus stays visible.
@@ -139,6 +138,7 @@ func (st *uiState) drawTabBar() {
 				labelW = utf8.RuneCountInString(label)
 			}
 			tabs = append(tabs, tabRect{
+				childID:    c.ID,
 				startCol:   col,
 				width:      w,
 				label:      label,
@@ -146,9 +146,6 @@ func (st *uiState) drawTabBar() {
 				glyphStyle: glyphStyle,
 				active:     active,
 			})
-			if tabs[len(tabs)-1].active {
-				activeTab = len(tabs) - 1
-			}
 			col += w
 		}
 	}
@@ -224,10 +221,9 @@ func (st *uiState) drawTabBar() {
 			hintCol, styleBorder, strings.Repeat("─", newHintW), styleReset)
 	}
 
-	if activeTab >= 0 {
+	for _, tab := range tabs {
-		tab := tabs[activeTab]
 		summaryWidth := tab.width - 2
-		if summary := st.activeSummaryText(summaryWidth); summary != "" {
+		if summary := st.summaryTextFor(tab.childID, summaryWidth); summary != "" {
 			fmt.Fprintf(&b, "\x1b[2;%dH %s%s%s", tab.startCol, styleDim, summary, styleReset)
 		}
 	}

internal/app/timers.go

@@ -58,6 +58,7 @@ type timerManager struct {
 	mu      sync.Mutex
 	nextID  int
 	timers  map[string]*pendingTimer
+	changes chan struct{}
 
 	// fireFn is the callback used to deliver the body to the owning
 	// process. Decoupled so tests can substitute a recorder. Defaults
@@ -69,11 +70,23 @@ func newTimerManager(sess *Session) *timerManager {
 	m := &timerManager{
 		sess:    sess,
 		timers:  make(map[string]*pendingTimer),
+		changes: make(chan struct{}, 1),
 	}
 	m.fireFn = defaultFireFn
 	return m
 }
 
+func (m *timerManager) changeEvents() <-chan struct{} {
+	return m.changes
+}
+
+func (m *timerManager) notifyChanged() {
+	select {
+	case m.changes <- struct{}{}:
+	default:
+	}
+}
+
 func defaultFireFn(owner *Child, body, label string) {
 	if owner == nil || !owner.IsLive() {
 		return
@@ -121,6 +134,7 @@ func (m *timerManager) TimerSet(ownerID string, body, label string, seconds floa
 	m.timers[id] = t
 	m.mu.Unlock()
 	t.rt = time.AfterFunc(d, func() { m.fireDelay(id) })
+	m.notifyChanged()
 	return id, nil
 }
 
@@ -136,6 +150,7 @@ func (m *timerManager) fireDelay(id string) {
 	body, label := t.body, t.label
 	delete(m.timers, id)
 	m.mu.Unlock()
+	m.notifyChanged()
 	m.fireFn(owner, body, label)
 }
 
@@ -214,6 +229,7 @@ func (m *timerManager) registerIdleTimer(kind pendingTimerKind, ownerID, body, l
 	}
 	m.timers[id] = t
 	m.mu.Unlock()
+	m.notifyChanged()
 	resp.ID = id
 	resp.Status = "pending"
 	return resp, nil
@@ -231,6 +247,7 @@ func (m *timerManager) fireIdleMaxWait(id string) {
 	body, label := t.body, t.label
 	delete(m.timers, id)
 	m.mu.Unlock()
+	m.notifyChanged()
 	m.fireFn(owner, body, label)
 }
 
@@ -291,6 +308,9 @@ func (m *timerManager) onChildStateChanged(childID string, state IdleState) {
 		delete(m.timers, id)
 	}
 	m.mu.Unlock()
+	if len(firedIDs) > 0 {
+		m.notifyChanged()
+	}
 	for _, f := range fires {
 		m.fireFn(f.owner, f.body, f.label)
 	}
@@ -320,7 +340,7 @@ func (m *timerManager) onChildStateChanged(childID string, state IdleState) {
 // legitimate fire and leave the parent never notified.
 func (m *timerManager) onChildClosed(childID string) {
 	m.mu.Lock()
-	defer m.mu.Unlock()
+	changed := false
 	for id, t := range m.timers {
 		if t.ownerID == childID {
 			if t.rt != nil {
@@ -329,6 +349,7 @@ func (m *timerManager) onChildClosed(childID string) {
 			}
 			t.status = timerStatusCanceled
 			delete(m.timers, id)
+			changed = true
 			continue
 		}
 		if !contains(t.watched, childID) {
@@ -344,6 +365,7 @@ func (m *timerManager) onChildClosed(childID string) {
 		if t.idleBaseline != nil {
 			delete(t.idleBaseline, childID)
 		}
+		changed = true
 		if len(t.watched) == 0 {
 			if t.rt != nil {
 				t.rt.Stop()
@@ -353,6 +375,10 @@ func (m *timerManager) onChildClosed(childID string) {
 			delete(m.timers, id)
 		}
 	}
+	m.mu.Unlock()
+	if changed {
+		m.notifyChanged()
+	}
 }
 
 // allWatchedIdleLocked reports whether every watched child is now
@@ -374,19 +400,21 @@ func (m *timerManager) allWatchedIdleLocked(t *pendingTimer) bool {
 // TimerCancel removes a pending or paused timer owned by ownerID.
 func (m *timerManager) TimerCancel(ownerID, id string) error {
 	m.mu.Lock()
-	defer m.mu.Unlock()
 	t, ok := m.timers[id]
 	if !ok {
+		m.mu.Unlock()
 		return mcp.Errorf(mcp.ErrorKindNotFound, "no such timer %q", id)
 	}
 	// Empty ownerID = top-level orchestrator caller (e.g. a non-agent
 	// MCP client); allow it to manage every timer in the session.
 	// Otherwise the caller's own id must match the timer's owner.
 	if ownerID != "" && t.ownerID != ownerID {
+		m.mu.Unlock()
 		return mcp.Errorf(mcp.ErrorKindRoleForbidden, "timer %q is not owned by caller", id)
 	}
 	if t.status == timerStatusFired || t.status == timerStatusCanceled {
 		// Cancelling a fired/cancelled timer is idempotent.
+		m.mu.Unlock()
 		return nil
 	}
 	if t.rt != nil {
@@ -395,6 +423,8 @@ func (m *timerManager) TimerCancel(ownerID, id string) error {
 	}
 	t.status = timerStatusCanceled
 	delete(m.timers, id)
+	m.mu.Unlock()
+	m.notifyChanged()
 	return nil
 }
 
@@ -402,18 +432,20 @@ func (m *timerManager) TimerCancel(ownerID, id string) error {
 // keeps the timer in the registry.
 func (m *timerManager) TimerPause(ownerID, id string) error {
 	m.mu.Lock()
-	defer m.mu.Unlock()
 	t, ok := m.timers[id]
 	if !ok {
+		m.mu.Unlock()
 		return mcp.Errorf(mcp.ErrorKindNotFound, "no such timer %q", id)
 	}
 	// Empty ownerID = top-level orchestrator caller (e.g. a non-agent
 	// MCP client); allow it to manage every timer in the session.
 	// Otherwise the caller's own id must match the timer's owner.
 	if ownerID != "" && t.ownerID != ownerID {
+		m.mu.Unlock()
 		return mcp.Errorf(mcp.ErrorKindRoleForbidden, "timer %q is not owned by caller", id)
 	}
 	if t.status != timerStatusPending {
+		m.mu.Unlock()
 		return mcp.Errorf(mcp.ErrorKindInvalidArgs, "timer %q is not pending", id)
 	}
 	if t.rt != nil {
@@ -429,6 +461,8 @@ func (m *timerManager) TimerPause(ownerID, id string) error {
 		t.pausedWasMaxWait = t.kind != timerKindDelay
 	}
 	t.status = timerStatusPaused
+	m.mu.Unlock()
+	m.notifyChanged()
 	return nil
 }
 
@@ -507,6 +541,7 @@ func (m *timerManager) TimerResume(ownerID, id string) error {
 		delete(m.timers, id)
 	}
 	m.mu.Unlock()
+	m.notifyChanged()
 	if fireNow {
 		m.fireFn(owner, body, label)
 	}
@@ -587,6 +622,56 @@ func (m *timerManager) activeForChild(id string) *mcp.TimerInfo {
 	return &info
 }
 
+const (
+	timerSidebarMinRefresh       = 50 * time.Millisecond
+	timerSidebarSubsecondRefresh = 100 * time.Millisecond
+)
+
+func nextTimerSidebarLabelChange(d time.Duration) time.Duration {
+	if d <= 0 {
+		return 0
+	}
+	if d < time.Second {
+		if d < timerSidebarSubsecondRefresh {
+			return d
+		}
+		return timerSidebarSubsecondRefresh
+	}
+
+	step := time.Second
+	if d >= time.Hour {
+		step = time.Hour
+	} else if d >= time.Minute {
+		step = time.Minute
+	}
+	wait := d % step
+	if wait <= 0 || wait < timerSidebarMinRefresh {
+		return timerSidebarMinRefresh
+	}
+	return wait
+}
+
+func (m *timerManager) nextSidebarRefreshAfter(now time.Time) (time.Duration, bool) {
+	m.mu.Lock()
+	defer m.mu.Unlock()
+	var best time.Duration
+	found := false
+	for _, t := range m.timers {
+		if t.status != timerStatusPending || t.firesAt.IsZero() {
+			continue
+		}
+		wait := nextTimerSidebarLabelChange(t.firesAt.Sub(now))
+		if wait <= 0 {
+			wait = timerSidebarMinRefresh
+		}
+		if !found || wait < best {
+			best = wait
+			found = true
+		}
+	}
+	return best, found
+}
+
 func isIdleState(s IdleState) bool {
 	return s == StateIdle
 }

internal/app/timers_test.go

@@ -65,6 +65,93 @@ func newTestManager(t *testing.T) (*Session, *timerManager, *recorderFire) {
 	return sess, mgr, rec
 }
 
+func waitTimerChange(t *testing.T, mgr *timerManager) {
+	t.Helper()
+	select {
+	case <-mgr.changeEvents():
+	case <-time.After(time.Second):
+		t.Fatal("timed out waiting for timer change signal")
+	}
+}
+
+func TestNextTimerSidebarLabelChange(t *testing.T) {
+	tests := []struct {
+		name string
+		d    time.Duration
+		want time.Duration
+	}{
+		{name: "minutes", d: 2*time.Minute + 10*time.Second, want: 10 * time.Second},
+		{name: "minute_to_seconds", d: time.Minute + 500*time.Millisecond, want: 500 * time.Millisecond},
+		{name: "seconds", d: 59*time.Second + 500*time.Millisecond, want: 500 * time.Millisecond},
+		{name: "subsecond", d: 500 * time.Millisecond, want: timerSidebarSubsecondRefresh},
+		{name: "nearly_done", d: 30 * time.Millisecond, want: 30 * time.Millisecond},
+	}
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			if got := nextTimerSidebarLabelChange(tt.d); got != tt.want {
+				t.Fatalf("nextTimerSidebarLabelChange(%s) = %s, want %s", tt.d, got, tt.want)
+			}
+		})
+	}
+}
+
+func TestTimerSidebarRefreshAfterUsesSoonestActiveBoundary(t *testing.T) {
+	_, mgr, _ := newTestManager(t)
+	now := time.Unix(123, 0)
+	mgr.mu.Lock()
+	mgr.timers["slow"] = &pendingTimer{
+		id:      "slow",
+		status:  timerStatusPending,
+		firesAt: now.Add(2*time.Minute + 10*time.Second),
+	}
+	mgr.timers["fast"] = &pendingTimer{
+		id:      "fast",
+		status:  timerStatusPending,
+		firesAt: now.Add(59*time.Second + 500*time.Millisecond),
+	}
+	mgr.timers["paused"] = &pendingTimer{
+		id:      "paused",
+		status:  timerStatusPaused,
+		firesAt: now.Add(100 * time.Millisecond),
+	}
+	mgr.mu.Unlock()
+
+	got, ok := mgr.nextSidebarRefreshAfter(now)
+	if !ok {
+		t.Fatal("nextSidebarRefreshAfter did not find active timers")
+	}
+	if got != 500*time.Millisecond {
+		t.Fatalf("nextSidebarRefreshAfter = %s, want 500ms", got)
+	}
+}
+
+func TestTimerManagerSignalsChangesForSidebar(t *testing.T) {
+	sess, mgr, _ := newTestManager(t)
+	owner := fakeChild("p_owner")
+	addChild(sess, owner)
+
+	id, err := mgr.TimerSet("p_owner", "x", "", 60)
+	if err != nil {
+		t.Fatalf("TimerSet: %v", err)
+	}
+	waitTimerChange(t, mgr)
+
+	if err := mgr.TimerPause("p_owner", id); err != nil {
+		t.Fatalf("TimerPause: %v", err)
+	}
+	waitTimerChange(t, mgr)
+
+	if err := mgr.TimerResume("p_owner", id); err != nil {
+		t.Fatalf("TimerResume: %v", err)
+	}
+	waitTimerChange(t, mgr)
+
+	if err := mgr.TimerCancel("p_owner", id); err != nil {
+		t.Fatalf("TimerCancel: %v", err)
+	}
+	waitTimerChange(t, mgr)
+}
+
 func TestTimerSetDelivers(t *testing.T) {
 	sess, mgr, rec := newTestManager(t)
 	c := fakeChild("p_owner")

internal/harness/restart_persist_test.go

@@ -143,7 +143,7 @@ func openSession(t *testing.T, env *testEnv, childEnv []string) *Session {
 	if err != nil {
 		t.Fatalf("vt emulator: %v", err)
 	}
-	p, err := pkgpty.Start([]string{env.PattermBin, "--project", env.ProjectDir}, childEnv, env.Cols, env.Rows)
+	p, err := pkgpty.Start([]string{env.PattermBin, "--project", env.ProjectDir}, childEnv, "", env.Cols, env.Rows)
 	if err != nil {
 		_ = em.Close()
 		t.Fatalf("pty start: %v", err)

internal/harness/scenarios/restart_process_keeps_chrome.json

@@ -0,0 +1,32 @@
+{
+  "name": "restart_process_keeps_chrome",
+  "cols": 120,
+  "rows": 40,
+  "scripts": [
+    {
+      "name": "slow-restart",
+      "body": "#!/bin/sh\ncount_file=\"$XDG_RUNTIME_DIR/slow-restart-count\"\nif [ -f \"$count_file\" ]; then\n  n=$(cat \"$count_file\")\nelse\n  n=0\nfi\nn=$((n + 1))\nprintf '%s\\n' \"$n\" > \"$count_file\"\nprintf 'SLOW READY %s\\n' \"$n\"\ntrap 'sleep 3; exit 0' TERM\nwhile true; do sleep 1; done\n"
+    }
+  ],
+  "steps": [
+    {
+      "type": "mcp_call",
+      "method": "spawn_process",
+      "params": { "kind": "command", "argv": ["slow-restart"], "name": "slow-restart" },
+      "save_as": "spawned"
+    },
+    {
+      "type": "mcp_call",
+      "method": "select_process",
+      "params": { "process_id": "{{spawned.process_id}}" }
+    },
+    { "type": "wait_text", "contains": "SLOW READY 1", "timeout_ms": 5000 },
+    { "type": "wait_stable", "timeout_ms": 2000 },
+    { "type": "assert_contains", "contains": "Processes" },
+    { "type": "send_text", "text": "\u000brestart\r" },
+    { "type": "wait_stable", "timeout_ms": 2000 },
+    { "type": "assert_contains", "contains": "Processes" },
+    { "type": "assert_contains", "contains": "slow-restart" },
+    { "type": "wait_text", "contains": "SLOW READY 2", "timeout_ms": 7000 }
+  ]
+}

internal/harness/session.go

@@ -55,7 +55,7 @@ func NewCLI(opts Options) (*Session, error) {
 	if err != nil {
 		return nil, err
 	}
-	p, err := pkgpty.Start([]string{env.PattermBin, "--project", env.ProjectDir}, childEnv, env.Cols, env.Rows)
+	p, err := pkgpty.Start([]string{env.PattermBin, "--project", env.ProjectDir}, childEnv, "", env.Cols, env.Rows)
 	if err != nil {
 		_ = em.Close()
 		return nil, err

internal/mcp/mcp.go

@@ -96,10 +96,34 @@ func (s *Server) acceptLoop() {
 // identity token (SPEC §10); we resolve it to a child id and stash that
 // as the caller for every subsequent tool call.
 func (s *Server) handleConn(conn net.Conn) {
-	defer conn.Close()
+	var writeMu sync.Mutex
+	var wg sync.WaitGroup
+	defer func() {
+		wg.Wait()
+		_ = conn.Close()
+	}()
 	r := bufio.NewReader(conn)
 
 	var callerID string
+	writeResp := func(resp []byte) bool {
+		if resp == nil {
+			return true
+		}
+		resp = append(resp, '\n')
+		writeMu.Lock()
+		defer writeMu.Unlock()
+		for len(resp) > 0 {
+			n, err := conn.Write(resp)
+			if err != nil {
+				return false
+			}
+			if n == 0 {
+				return false
+			}
+			resp = resp[n:]
+		}
+		return true
+	}
 
 	greeting, err := r.ReadBytes('\n')
 	if err != nil {
@@ -115,24 +139,21 @@ func (s *Server) handleConn(conn net.Conn) {
 	} else {
 		// Treat as a real request from an unknown caller.
 		resp := s.dispatch("", greeting)
-		if resp != nil {
+		if !writeResp(resp) {
-			resp = append(resp, '\n')
-			if _, werr := conn.Write(resp); werr != nil {
 			return
 		}
 	}
-	}
 
 	for {
 		line, err := r.ReadBytes('\n')
 		if len(line) > 0 {
-			resp := s.dispatch(callerID, line)
+			req := append([]byte(nil), line...)
-			if resp != nil {
+			wg.Add(1)
-				resp = append(resp, '\n')
+			go func() {
-				if _, werr := conn.Write(resp); werr != nil {
+				defer wg.Done()
-					return
+				resp := s.dispatch(callerID, req)
-				}
+				_ = writeResp(resp)
-			}
+			}()
 		}
 		if err != nil {
 			return

internal/mcp/mcp_test.go

@@ -0,0 +1,190 @@
+package mcp
+
+import (
+	"bufio"
+	"encoding/json"
+	"fmt"
+	"net"
+	"sync"
+	"syscall"
+	"testing"
+	"time"
+
+	"github.com/hjbdev/patterm/internal/scratchpad"
+)
+
+func TestHandleConnDispatchesRequestsConcurrently(t *testing.T) {
+	serverConn, clientConn := net.Pipe()
+	t.Cleanup(func() { _ = clientConn.Close() })
+
+	host := &blockingToolHost{
+		waitEntered: make(chan struct{}),
+		waitRelease: make(chan struct{}),
+	}
+	s := &Server{}
+	s.SetHost(host)
+	done := make(chan struct{})
+	go func() {
+		s.handleConn(serverConn)
+		close(done)
+	}()
+
+	reader := bufio.NewReader(clientConn)
+	writeLine(t, clientConn, `{"patterm_identity":"ident"}`)
+	writeLine(t, clientConn, `{"jsonrpc":"2.0","id":1,"method":"wait_for_pattern","params":{"process_id":"p_slow","pattern":"never","timeout_seconds":300}}`)
+	select {
+	case <-host.waitEntered:
+	case <-time.After(time.Second):
+		t.Fatal("wait_for_pattern did not enter fake host")
+	}
+
+	writeLine(t, clientConn, `{"jsonrpc":"2.0","id":2,"method":"get_process_status","params":{"process_id":"p_fast"}}`)
+	fast := readJSONRPCResponse(t, clientConn, reader, time.Second)
+	if got := string(fast.ID); got != "2" {
+		t.Fatalf("first response id = %s, want 2; response=%s", got, fast.Raw)
+	}
+	if fast.Error != nil {
+		t.Fatalf("fast response returned error: %+v", fast.Error)
+	}
+
+	_ = clientConn.SetReadDeadline(time.Now().Add(50 * time.Millisecond))
+	if line, err := reader.ReadBytes('\n'); err == nil {
+		t.Fatalf("slow response arrived before release: %s", line)
+	}
+
+	close(host.waitRelease)
+	slow := readJSONRPCResponse(t, clientConn, reader, time.Second)
+	if got := string(slow.ID); got != "1" {
+		t.Fatalf("second response id = %s, want 1; response=%s", got, slow.Raw)
+	}
+	if slow.Error != nil {
+		t.Fatalf("slow response returned error: %+v", slow.Error)
+	}
+
+	_ = clientConn.Close()
+	select {
+	case <-done:
+	case <-time.After(time.Second):
+		t.Fatal("handleConn did not exit after client close")
+	}
+}
+
+type jsonRPCResponse struct {
+	Raw    string
+	ID     json.RawMessage    `json:"id"`
+	Result map[string]any     `json:"result"`
+	Error  *jsonRPCErrorShape `json:"error"`
+}
+
+type jsonRPCErrorShape struct {
+	Code    int    `json:"code"`
+	Message string `json:"message"`
+}
+
+func writeLine(t *testing.T, conn net.Conn, line string) {
+	t.Helper()
+	_ = conn.SetWriteDeadline(time.Now().Add(time.Second))
+	if _, err := fmt.Fprintln(conn, line); err != nil {
+		t.Fatalf("write %s: %v", line, err)
+	}
+}
+
+func readJSONRPCResponse(t *testing.T, conn net.Conn, reader *bufio.Reader, timeout time.Duration) jsonRPCResponse {
+	t.Helper()
+	_ = conn.SetReadDeadline(time.Now().Add(timeout))
+	line, err := reader.ReadBytes('\n')
+	if err != nil {
+		t.Fatalf("read response: %v", err)
+	}
+	var resp jsonRPCResponse
+	resp.Raw = string(line)
+	if err := json.Unmarshal(line, &resp); err != nil {
+		t.Fatalf("parse response %s: %v", line, err)
+	}
+	return resp
+}
+
+type blockingToolHost struct {
+	waitEntered chan struct{}
+	waitRelease chan struct{}
+	waitOnce    sync.Once
+}
+
+func (h *blockingToolHost) ResolveCallerIdentity(identity string) string { return "caller-" + identity }
+func (h *blockingToolHost) CallerRole(string) CallerRole                 { return RoleOrchestrator }
+func (h *blockingToolHost) SpawnAgent(string, SpawnAgentArgs) (ProcessInfo, error) {
+	return ProcessInfo{}, nil
+}
+func (h *blockingToolHost) SpawnProcess(string, SpawnProcessArgs) (ProcessInfo, error) {
+	return ProcessInfo{}, nil
+}
+func (h *blockingToolHost) StartProcess(string, string) (ProcessInfo, error) {
+	return ProcessInfo{}, nil
+}
+func (h *blockingToolHost) RestartProcess(string, string, syscall.Signal) (ProcessInfo, error) {
+	return ProcessInfo{}, nil
+}
+func (h *blockingToolHost) StopProcess(string, string, syscall.Signal) (ProcessInfo, error) {
+	return ProcessInfo{}, nil
+}
+func (h *blockingToolHost) CloseProcess(string, string) error          { return nil }
+func (h *blockingToolHost) RenameProcess(string, string, string) error { return nil }
+func (h *blockingToolHost) SelectProcess(string, string) error         { return nil }
+func (h *blockingToolHost) ListProcesses(string, string) []ProcessInfo { return nil }
+func (h *blockingToolHost) GetProcessStatus(string, string) (ProcessStatus, error) {
+	return ProcessStatus{ProcessInfo: ProcessInfo{ID: "p_fast", Status: "running"}}, nil
+}
+func (h *blockingToolHost) GetProjectStatus(string) (ProjectStatus, error) {
+	return ProjectStatus{}, nil
+}
+func (h *blockingToolHost) GetProcessOutput(string, string, string, int64) (ProcessOutput, error) {
+	return ProcessOutput{}, nil
+}
+func (h *blockingToolHost) GetProcessRawOutput(string, string, int64) (RawOutput, error) {
+	return RawOutput{}, nil
+}
+func (h *blockingToolHost) SearchOutput(string, string, string, string, int) (SearchResult, error) {
+	return SearchResult{}, nil
+}
+func (h *blockingToolHost) WaitForPattern(string, string, string, float64, string) (bool, string, error) {
+	h.waitOnce.Do(func() { close(h.waitEntered) })
+	<-h.waitRelease
+	return true, "matched", nil
+}
+func (h *blockingToolHost) GetProcessPorts(string, string) ([]PortSighting, error) {
+	return nil, nil
+}
+func (h *blockingToolHost) SendInput(string, SendInputArgs) (SendInputResult, error) {
+	return SendInputResult{}, nil
+}
+func (h *blockingToolHost) SendMessage(string, string, string) error           { return nil }
+func (h *blockingToolHost) RequestHumanAttention(string, string, string) error { return nil }
+func (h *blockingToolHost) TimerWait(string, float64, string) (string, error) {
+	return "", nil
+}
+func (h *blockingToolHost) TimerSet(string, TimerSetArgs) (TimerHandle, error) {
+	return TimerHandle{}, nil
+}
+func (h *blockingToolHost) TimerFireWhenIdleAny(string, TimerFireWhenIdleArgs) (TimerFireWhenIdleResponse, error) {
+	return TimerFireWhenIdleResponse{}, nil
+}
+func (h *blockingToolHost) TimerFireWhenIdleAll(string, TimerFireWhenIdleArgs) (TimerFireWhenIdleResponse, error) {
+	return TimerFireWhenIdleResponse{}, nil
+}
+func (h *blockingToolHost) TimerCancel(string, string) error { return nil }
+func (h *blockingToolHost) TimerPause(string, string) error  { return nil }
+func (h *blockingToolHost) TimerResume(string, string) error { return nil }
+func (h *blockingToolHost) TimerList(string) ([]TimerInfo, error) {
+	return nil, nil
+}
+func (h *blockingToolHost) ScratchpadList() ([]scratchpad.Entry, error) { return nil, nil }
+func (h *blockingToolHost) ScratchpadRead(string) (string, string, error) {
+	return "", "", nil
+}
+func (h *blockingToolHost) ScratchpadWrite(string, string, string) (string, error) {
+	return "", nil
+}
+func (h *blockingToolHost) ScratchpadAppend(string, string) error { return nil }
+func (h *blockingToolHost) ScratchpadDelete(string) error         { return nil }
+func (h *blockingToolHost) WhoAmI(string) WhoAmI                  { return WhoAmI{} }
+func (h *blockingToolHost) Help(string, string) HelpResponse      { return HelpResponse{} }

internal/mcp/protocol.go

@@ -358,6 +358,13 @@ func toolCatalog() []toolDescriptor {
 				"content": stringProp("Text to append."),
 			}, []string{"name", "content"}),
 		},
+		{
+			Name:        "scratchpad_delete",
+			Description: "Delete a scratchpad entry.",
+			InputSchema: objectSchema(map[string]any{
+				"name": stringProp("Scratchpad name."),
+			}, []string{"name"}),
+		},
 		{
 			Name:        "whoami",
 			Description: "Return the caller's identity, role, parent, project metadata, and available tools.",

internal/mcp/tools.go

@@ -101,6 +101,7 @@ type ToolHost interface {
 	ScratchpadRead(name string) (content string, revision string, err error)
 	ScratchpadWrite(name, content, expectedRevision string) (revision string, err error)
 	ScratchpadAppend(name, content string) error
+	ScratchpadDelete(name string) error
 
 	// Meta.
 	WhoAmI(callerID string) WhoAmI
@@ -776,6 +777,18 @@ func callTool(h ToolHost, callerID, method string, params json.RawMessage) (any,
 		}
 		return map[string]any{"ok": true}, 0, "", nil
 
+	case "scratchpad_delete":
+		var p struct {
+			Name string `json:"name"`
+		}
+		if err := unmarshalParams(params, &p); err != nil {
+			return nil, codeInvalidParams, err.Error(), nil
+		}
+		if err := h.ScratchpadDelete(p.Name); err != nil {
+			return nil, codeInternal, err.Error(), nil
+		}
+		return map[string]any{"ok": true}, 0, "", nil
+
 	case "whoami":
 		return h.WhoAmI(callerID), 0, "", nil
 

internal/preset/preset.go

@@ -352,7 +352,10 @@ func defaultAgentPresets() []*Preset {
   "ready_signal": { "idle_ms": 1000 },
   "idle_detection": {
     "strategy": "osc_title_stability",
-    "idle_threshold_ms": 2000
+    "idle_threshold_ms": 2000,
+    "thinking_patterns": [
+      "(?i)esc to interrupt"
+    ]
   },
   "chrome_trim_hints": [
     "^OpenAI Codex",

internal/preset/preset_test.go

@@ -27,6 +27,13 @@ func TestLoadUsesBuiltInDefaultsWithoutWritingConfig(t *testing.T) {
 	if claude.IdleDetection == nil || len(claude.IdleDetection.PermissionPatterns) == 0 {
 		t.Fatalf("built-in claude missing permission patterns: %+v", claude.IdleDetection)
 	}
+	codex := presetByName(set.Agents, "codex")
+	if codex == nil {
+		t.Fatal("missing built-in codex preset")
+	}
+	if codex.IdleDetection == nil || len(codex.IdleDetection.ThinkingPatterns) == 0 {
+		t.Fatalf("built-in codex missing thinking patterns: %+v", codex.IdleDetection)
+	}
 }
 
 func TestLoadMergesUserOverlayIntoBuiltInPreset(t *testing.T) {

internal/protocol/frame.go

@@ -0,0 +1,164 @@
+// Package protocol defines the daemon/client control frames shared by
+// transports. It intentionally contains data shapes only; app behavior stays
+// in internal/app until the headless daemon split is complete.
+package protocol
+
+import (
+	"encoding/json"
+	"fmt"
+	"time"
+)
+
+// FrameType identifies one protocol message kind.
+type FrameType string
+
+const (
+	FrameHello          FrameType = "hello"
+	FrameAuthChallenge  FrameType = "auth_challenge"
+	FrameAuthOK         FrameType = "auth_ok"
+	FrameAttach         FrameType = "attach"
+	FrameDetach         FrameType = "detach"
+	FrameProjectList    FrameType = "project_list"
+	FrameChrome         FrameType = "chrome"
+	FramePaneSnapshot   FrameType = "pane_snapshot"
+	FramePaneChunk      FrameType = "pane_chunk"
+	FrameLifecycle      FrameType = "lifecycle"
+	FrameAttention      FrameType = "attention"
+	FrameTrustPrompt    FrameType = "trust_prompt"
+	FrameInput          FrameType = "input"
+	FrameFocus          FrameType = "focus"
+	FrameSwitchProject  FrameType = "switch_project"
+	FrameOpenProject    FrameType = "open_project"
+	FramePaletteCommand FrameType = "palette_command"
+	FrameTrustResponse  FrameType = "trust_response"
+	FrameResize         FrameType = "resize"
+)
+
+// Frame is the transport envelope. Payload is deliberately raw JSON so
+// network transports can frame without knowing every message type; loopback
+// transports may pass the same bytes without JSON re-encoding.
+type Frame struct {
+	Type      FrameType       `json:"type"`
+	RequestID string          `json:"request_id,omitempty"`
+	Payload   json.RawMessage `json:"payload,omitempty"`
+}
+
+// NewFrame marshals payload into a protocol frame.
+func NewFrame[T any](typ FrameType, payload T) (Frame, error) {
+	b, err := json.Marshal(payload)
+	if err != nil {
+		return Frame{}, fmt.Errorf("protocol: marshal %s: %w", typ, err)
+	}
+	return Frame{Type: typ, Payload: b}, nil
+}
+
+// Decode unmarshals f.Payload into v.
+func Decode[T any](f Frame) (T, error) {
+	var v T
+	if len(f.Payload) == 0 {
+		return v, nil
+	}
+	if err := json.Unmarshal(f.Payload, &v); err != nil {
+		return v, fmt.Errorf("protocol: decode %s: %w", f.Type, err)
+	}
+	return v, nil
+}
+
+type Hello struct {
+	Version    int    `json:"version"`
+	DaemonID   string `json:"daemon_id,omitempty"`
+	ClientID   string `json:"client_id,omitempty"`
+	ProjectKey string `json:"project_key,omitempty"`
+}
+
+type Attach struct {
+	Token      string `json:"token,omitempty"`
+	ProjectKey string `json:"project_key,omitempty"`
+	TermSize   Size   `json:"term_size"`
+}
+
+type Detach struct {
+	ClientID string `json:"client_id,omitempty"`
+}
+
+type Size struct {
+	Cols uint16 `json:"cols"`
+	Rows uint16 `json:"rows"`
+}
+
+type Project struct {
+	Key        string    `json:"key"`
+	Path       string    `json:"path"`
+	Name       string    `json:"name"`
+	LastActive time.Time `json:"last_active,omitempty"`
+	TabCount   int       `json:"tab_count"`
+}
+
+type ProjectList struct {
+	Projects []Project `json:"projects"`
+}
+
+type Chrome struct {
+	ProjectKey string          `json:"project_key"`
+	Model      json.RawMessage `json:"model"`
+}
+
+type PaneSnapshot struct {
+	PaneID string `json:"pane_id"`
+	Bytes  []byte `json:"bytes"`
+}
+
+type PaneChunk struct {
+	PaneID string `json:"pane_id"`
+	Bytes  []byte `json:"bytes"`
+}
+
+type LifecycleKind string
+
+const (
+	LifecycleSpawned      LifecycleKind = "spawned"
+	LifecycleExited       LifecycleKind = "exited"
+	LifecycleClosed       LifecycleKind = "closed"
+	LifecycleStateChanged LifecycleKind = "state_changed"
+)
+
+type Lifecycle struct {
+	Kind       LifecycleKind   `json:"kind"`
+	ProjectKey string          `json:"project_key,omitempty"`
+	ChildID    string          `json:"child_id,omitempty"`
+	Child      json.RawMessage `json:"child,omitempty"`
+	State      string          `json:"state,omitempty"`
+}
+
+type Input struct {
+	PaneID string `json:"pane_id"`
+	Bytes  []byte `json:"bytes"`
+}
+
+type Focus struct {
+	PaneID string `json:"pane_id,omitempty"`
+	Pad    string `json:"pad,omitempty"`
+}
+
+type SwitchProject struct {
+	Key string `json:"key"`
+}
+
+type OpenProject struct {
+	Path string `json:"path"`
+}
+
+type PaletteCommand struct {
+	Kind string          `json:"kind"`
+	Data json.RawMessage `json:"data,omitempty"`
+}
+
+type TrustResponse struct {
+	ProcessID string `json:"process_id"`
+	Preset    string `json:"preset"`
+	Allow     bool   `json:"allow"`
+}
+
+type Resize struct {
+	Size Size `json:"size"`
+}

internal/protocol/loopback.go

@@ -0,0 +1,67 @@
+package protocol
+
+import (
+	"sync"
+)
+
+const defaultLoopbackBuffer = 64
+
+// NewLoopbackPair returns connected in-process transports. Frames cross the
+// same Send/Recv boundary as network transports, but payload bytes are passed
+// directly without JSON re-encoding.
+func NewLoopbackPair() (client Transport, daemon Transport) {
+	c2d := make(chan Frame, defaultLoopbackBuffer)
+	d2c := make(chan Frame, defaultLoopbackBuffer)
+	return &loopbackTransport{send: c2d, recv: d2c}, &loopbackTransport{send: d2c, recv: c2d}
+}
+
+type loopbackTransport struct {
+	send chan<- Frame
+	recv <-chan Frame
+	once sync.Once
+	done chan struct{}
+}
+
+func (t *loopbackTransport) init() {
+	if t.done == nil {
+		t.done = make(chan struct{})
+	}
+}
+
+func (t *loopbackTransport) Send(f Frame) error {
+	t.init()
+	select {
+	case <-t.done:
+		return ErrTransportClosed
+	case t.send <- cloneFrame(f):
+		return nil
+	}
+}
+
+func (t *loopbackTransport) Recv() (Frame, error) {
+	t.init()
+	select {
+	case <-t.done:
+		return Frame{}, ErrTransportClosed
+	case f, ok := <-t.recv:
+		if !ok {
+			return Frame{}, ErrTransportClosed
+		}
+		return f, nil
+	}
+}
+
+func (t *loopbackTransport) Close() error {
+	t.init()
+	t.once.Do(func() {
+		close(t.done)
+	})
+	return nil
+}
+
+func cloneFrame(f Frame) Frame {
+	if len(f.Payload) > 0 {
+		f.Payload = append([]byte(nil), f.Payload...)
+	}
+	return f
+}

internal/protocol/loopback_test.go

@@ -0,0 +1,51 @@
+package protocol
+
+import "testing"
+
+func TestLoopbackUsesFramePayload(t *testing.T) {
+	client, daemon := NewLoopbackPair()
+	defer client.Close()
+	defer daemon.Close()
+
+	sent, err := NewFrame(FrameInput, Input{PaneID: "p_123456", Bytes: []byte("hello")})
+	if err != nil {
+		t.Fatalf("NewFrame: %v", err)
+	}
+	if err := client.Send(sent); err != nil {
+		t.Fatalf("Send: %v", err)
+	}
+	got, err := daemon.Recv()
+	if err != nil {
+		t.Fatalf("Recv: %v", err)
+	}
+	if got.Type != FrameInput {
+		t.Fatalf("type = %q, want %q", got.Type, FrameInput)
+	}
+	payload, err := Decode[Input](got)
+	if err != nil {
+		t.Fatalf("Decode: %v", err)
+	}
+	if payload.PaneID != "p_123456" || string(payload.Bytes) != "hello" {
+		t.Fatalf("payload = %#v", payload)
+	}
+}
+
+func TestLoopbackCopiesPayloadOnSend(t *testing.T) {
+	client, daemon := NewLoopbackPair()
+	defer client.Close()
+	defer daemon.Close()
+
+	f := Frame{Type: FramePaneChunk, Payload: []byte(`{"pane_id":"p","bytes":"aGVsbG8="}`)}
+	if err := client.Send(f); err != nil {
+		t.Fatalf("Send: %v", err)
+	}
+	f.Payload[0] = 'x'
+
+	got, err := daemon.Recv()
+	if err != nil {
+		t.Fatalf("Recv: %v", err)
+	}
+	if got.Payload[0] != '{' {
+		t.Fatalf("payload was retained instead of copied: %q", string(got.Payload))
+	}
+}

internal/protocol/transport.go

@@ -0,0 +1,73 @@
+package protocol
+
+import (
+	"bufio"
+	"encoding/json"
+	"errors"
+	"fmt"
+	"io"
+	"net"
+)
+
+var ErrTransportClosed = errors.New("protocol: transport closed")
+
+// Transport carries framed daemon/client protocol messages.
+type Transport interface {
+	Send(Frame) error
+	Recv() (Frame, error)
+	Close() error
+}
+
+// ConnTransport is a JSON-lines implementation over a stream connection.
+type ConnTransport struct {
+	conn net.Conn
+	r    *bufio.Reader
+	w    *bufio.Writer
+}
+
+func NewConnTransport(conn net.Conn) *ConnTransport {
+	return &ConnTransport{
+		conn: conn,
+		r:    bufio.NewReader(conn),
+		w:    bufio.NewWriter(conn),
+	}
+}
+
+func (t *ConnTransport) Send(f Frame) error {
+	if t == nil || t.conn == nil {
+		return ErrTransportClosed
+	}
+	b, err := json.Marshal(f)
+	if err != nil {
+		return fmt.Errorf("protocol: encode frame: %w", err)
+	}
+	if _, err := t.w.Write(append(b, '\n')); err != nil {
+		return err
+	}
+	return t.w.Flush()
+}
+
+func (t *ConnTransport) Recv() (Frame, error) {
+	if t == nil || t.conn == nil {
+		return Frame{}, ErrTransportClosed
+	}
+	line, err := t.r.ReadBytes('\n')
+	if err != nil {
+		if errors.Is(err, io.EOF) {
+			return Frame{}, ErrTransportClosed
+		}
+		return Frame{}, err
+	}
+	var f Frame
+	if err := json.Unmarshal(line, &f); err != nil {
+		return Frame{}, fmt.Errorf("protocol: decode frame: %w", err)
+	}
+	return f, nil
+}
+
+func (t *ConnTransport) Close() error {
+	if t == nil || t.conn == nil {
+		return nil
+	}
+	return t.conn.Close()
+}

internal/pty/pty.go

@@ -6,6 +6,7 @@ import (
 	"io"
 	"os"
 	"os/exec"
+	"syscall"
 
 	cpty "github.com/creack/pty"
 )
@@ -19,11 +20,13 @@ type PTY struct {
 // Start spawns argv with stdin/stdout/stderr attached to a new PTY sized
 // (cols, rows). The returned PTY exposes the master fd for the parent to
 // read from and write to.
-func Start(argv []string, env []string, cols, rows uint16) (*PTY, error) {
+func Start(argv []string, env []string, workDir string, cols, rows uint16) (*PTY, error) {
 	if len(argv) == 0 {
 		return nil, fmt.Errorf("pty: empty argv")
 	}
 	cmd := exec.Command(argv[0], argv[1:]...)
+	cmd.Dir = workDir
+	cmd.SysProcAttr = &syscall.SysProcAttr{Setsid: true, Setctty: true}
 	if env != nil {
 		cmd.Env = ensureTerm(env)
 	} else {
@@ -88,6 +91,10 @@ func (p *PTY) Close() error {
 		p.master = nil
 	}
 	if p.cmd != nil && p.cmd.Process != nil {
+		pid := p.cmd.Process.Pid
+		if pid > 0 {
+			_ = syscall.Kill(-pid, syscall.SIGKILL)
+		}
 		_ = p.cmd.Process.Kill()
 	}
 	return firstErr

internal/pty/pty_test.go

@@ -0,0 +1,84 @@
+package pty
+
+import (
+	"bytes"
+	"errors"
+	"os"
+	"path/filepath"
+	"strconv"
+	"strings"
+	"syscall"
+	"testing"
+	"time"
+)
+
+func TestStartUsesWorkDir(t *testing.T) {
+	dir := t.TempDir()
+	p, err := Start([]string{"sh", "-c", "pwd"}, nil, dir, 80, 24)
+	if err != nil {
+		t.Fatalf("Start: %v", err)
+	}
+	defer p.Close()
+
+	var out bytes.Buffer
+	buf := make([]byte, 256)
+	deadline := time.Now().Add(5 * time.Second)
+	for time.Now().Before(deadline) {
+		n, err := p.Read(buf)
+		if n > 0 {
+			out.Write(buf[:n])
+			if strings.Contains(out.String(), dir) {
+				break
+			}
+		}
+		if err != nil {
+			break
+		}
+	}
+	_ = p.Wait()
+
+	if got := strings.TrimSpace(out.String()); got != dir {
+		t.Fatalf("pwd output = %q, want %q", got, dir)
+	}
+}
+
+func TestCloseKillsProcessGroup(t *testing.T) {
+	dir := t.TempDir()
+	pidFile := filepath.Join(dir, "sleep.pid")
+	env := append(os.Environ(), "PIDFILE="+pidFile)
+	p, err := Start([]string{"sh", "-c", "sleep 30 & echo $! > \"$PIDFILE\"; wait"}, env, "", 80, 24)
+	if err != nil {
+		t.Fatalf("Start: %v", err)
+	}
+	deadline := time.Now().Add(5 * time.Second)
+	var childPID int
+	for time.Now().Before(deadline) {
+		b, err := os.ReadFile(pidFile)
+		if err == nil {
+			childPID, _ = strconv.Atoi(strings.TrimSpace(string(b)))
+			if childPID > 0 {
+				break
+			}
+		}
+		time.Sleep(20 * time.Millisecond)
+	}
+	if childPID <= 0 {
+		_ = p.Close()
+		t.Fatalf("background child pid was not written")
+	}
+
+	if err := p.Close(); err != nil {
+		t.Fatalf("Close: %v", err)
+	}
+	_ = p.Wait()
+
+	deadline = time.Now().Add(5 * time.Second)
+	for time.Now().Before(deadline) {
+		err := syscall.Kill(childPID, 0)
+		if errors.Is(err, syscall.ESRCH) {
+			return
+		}
+		time.Sleep(20 * time.Millisecond)
+	}
+	t.Fatalf("background child pid %d still exists after PTY.Close", childPID)
+}