Chat: the composer shows Claude Code's suggested next prompt (#727, D281)

cmd/contr/e2e_harness_test.go

@@ -118,6 +118,7 @@ func newHarness(t *testing.T) *harness {
 	cfg.Profiles["sizer"] = agents.Profile{Argv: []string{"sh", "-c",
 		`draw() { printf "\033[2J\033[H"; set -- $(stty size); echo "grid $2x$1"; i=0; while [ $i -lt $2 ]; do printf %d $((i % 10)); i=$((i+1)); done; echo; }; trap draw WINCH; draw; while :; do sleep 1; done`}}
 	cfg.Profiles["claude-idle"] = agents.Profile{Argv: []string{claude, "idle"}}
+	cfg.Profiles["claude-next"] = agents.Profile{Argv: []string{claude, "idle:next=commit%20this%20and%20open%20a%20PR"}}
 	cfg.Profiles["claude-working"] = agents.Profile{Argv: []string{claude, "working"}}
 	cfg.Profiles["claude-blocked"] = agents.Profile{Argv: []string{claude, "blocked:kind=permission:msg=Allow%20rm"}}
 	cfg.Profiles["claude-error"] = agents.Profile{Argv: []string{claude, "error"}}

cmd/contr/e2e_see_test.go

@@ -197,6 +197,12 @@ var seeFixtures = map[string]seeFixture{
 		ready: "lead, ",
 		press: []string{"Chat"},
 	},
+	"chat-next": {
+		about: "the chat fixture with lead idle and a suggested next prompt in its terminal's input line (D281): the composer shows it in place of the placeholder",
+		setup: func(t *testing.T, h *harness) { seeChatAs(t, h, "claude-next") },
+		ready: "lead, ",
+		press: []string{"Chat"},
+	},
 	"chat-blocks": {
 		about: "the orchestrator lead in Chat mode with an older status board (frozen: the agent's three columns, its answer's time), the live board (state, PR and checks from a fake gh: CI running 2 of 3, CI passed 3 of 3, building, waiting, and a worker that is not found) and a merge queue (merged, CI running, blocked: 1 check failed, a note) (D267)",
 		setup: seeChatBlocks,

cmd/contr/e2e_titlebar_test.go

@@ -23,7 +23,8 @@ import (
 
 // fakeClaude is a program that looks like Claude Code in a terminal: the welcome box, the
 // conversation, a status line and the prompt box. It tells hc its state with the OSC the hook
-// sends (last argument: working, idle, error or blocked:kind=...:msg=..., which also prints a permission menu).
+// sends (last argument: working, idle, error or blocked:kind=...:msg=..., which also prints a permission menu;
+// idle:next=... prints a suggested next prompt, faint, in the input line).
 const fakeClaude = `package main
 
 import (
@@ -57,8 +58,17 @@ func main() {
 		fmt.Printf("\x1b]7501;state=%s\x07", state)
 		time.Sleep(time.Hour)
 	}
+	next := ""
+	if i := strings.Index(state, ":next="); i >= 0 {
+		// The suggested next prompt, faint after the mark as Claude Code draws it (D281).
+		state, next = state[:i], strings.ReplaceAll(state[i+len(":next="):], "%20", " ")
+	}
 	fmt.Print("╭───────────────────────────────────────────────────╮\n")
-	fmt.Print("│ >                                                 │\n")
+	if next != "" {
+		fmt.Printf("❯ \x1b[2m%s\x1b[0m\n", next)
+	} else {
+		fmt.Print("│ >                                                 │\n")
+	}
 	fmt.Print("╰───────────────────────────────────────────────────╯\n")
 	fmt.Print("  ? for shortcuts\n")
 	fmt.Printf("\x1b]7501;state=%s\x07", state)

docs/DECISIONS.md

@@ -255,4 +255,5 @@ replaces it.
 | D278 | 2026-11-11 | Settings → Setup: a read-only setup checklist (#713, S1). `Setup` is the first Settings tab: `Setup`, `General`, `Agents`, `Updates` (changes the tab list of D186). Package `internal/setup` checks hc (`hc --version`), the hc core (the frame's live state), the contr plugin (`claude plugin list --json`), the Claude meter (data under 24 h old), gh (`gh auth status`), and the optional codex and `contr` command. Each command has a 5 s limit and runs off the UI thread when Settings opens, on Recheck, and on activation while the tab shows; nothing runs while Settings is closed. No check reads files in `~/.claude` or `~/.codex`. A step shows a line with a Copy button; contr runs no command here (S3 adds a confirmed plugin install, D65) and never edits Claude Code's settings (the meter stays copy only, D66). The Setup tab and the sidebar Settings button get the D146 dot while a required check is not ready. Spec: `docs/spec/SettingsSetup.md`. | Owner, issue #713: a new Mac shows what is missing in one place. |
 | D279 | 2026-11-11 | The composer completes file paths with "@" (#708, tracker #634; docs/spec/ChatView.md, Path popup). "@" at the caret, at the start or after a space, opens the popup of D273 with the paths of the session's working folder: `git ls-files --cached --others --exclude-standard` (no ignored files, no deleted ones) with their folders, or a plain read of the typed folder outside git. Parts that start with the text first, then paths that hold it, at most 50. A folder goes in as "@dir/" and keeps the popup open. The popup logic takes a query at the caret (`QueryAt`) for both "/" and "@", so there is one popup with two sources. |
 | D280 | 2026-11-11 | The first launch opens Settings → Setup (#713, S2). The setup checks of D278 run once at start, off the UI thread, after the window shows, so the D146 dot shows without opening Settings; then only when Settings opens, on Recheck and on activation while the tab shows; no timer. When the start pass finds a required check not ready (the hc core not counted: it can still be connecting) and `setupSeen` in the settings file is false, Settings opens on the Setup tab once and `setupSeen` is stored. It never opens by itself again. Spec: `docs/spec/SettingsSetup.md`. | Owner, issue #713: a new Mac shows what is missing without a search. |
+| D281 | 2026-11-11 | The composer shows Claude Code's suggested next prompt (#727, tracker #634). Claude Code does not write the suggestion to the transcript (it is made with the transcript off) and `terminal.read` gives text without styles, so contr reads the selected terminal's screen as escape sequences (the MyGo terminal's `Snapshot`) and takes the text after the last `❯` only when all of it is faint (SGR 2), as a real session draws it; typed text, a sent prompt or a menu choice is not faint. The read runs 300 ms after output, off the UI thread, through a new `OnOutput` hook of `ghostty.Conn`. While the field is empty, the suggestion is the field's placeholder; Tab or Right takes it, after the slash popup's Tab. Only the selected terminal has a screen, so other sessions show none (docs/spec/ChatView.md, Composer). | Owner in #727. |
 | D282 | 2026-11-11 | A Claude worker gets the PATH of the process that spawns it (#728). `hc update` restarts the core under launchd, whose PATH is short, and each terminal inherits the PATH of the core, so `claude` was not found and the worker ended at once. Spawn now sets `CONTR_PATH` in the terminal: the PATH of the spawning process, then `~/.local/bin`, `/opt/homebrew/bin` and `/usr/local/bin`, without doubles. The clean wrapper (D216) adds these folders after the PATH of the core and removes the variable, so the PATH of the core still comes first. A program that does not start through the clean wrapper (not Claude) gets no change. | Seen on 2026-11-11 after the first `Update hc` (D277): two spawns ended with "claude: not found". |

docs/spec/ChatView.md

@@ -143,6 +143,15 @@ the circle.
 - The field takes the focus as it appears: when the chat shows (the switch,
   ⌘E). It keeps the focus after a send, and takes it back after a click on
   Send or Stop.
+- Suggested next prompt (D281): when a turn ends, Claude Code shows a
+  suggested next prompt as faint text after `❯` in its input line. contr
+  reads it from the selected terminal's screen (the faint text, SGR 2, after
+  the last `❯`), 300 ms after output, off the UI thread. While the field is
+  empty, the suggestion takes the place of the placeholder, in the same
+  `ink-48`. Tab or Right puts it into the field (the slash popup takes Tab
+  first while it shows). Enter with an empty field sends nothing. Typed text
+  hides it; a new turn clears the input line, so it goes. No suggestion: the
+  placeholder.
 - Enter sends, and so does a click on Send; ⇧Enter breaks the line. A blank field sends nothing. Send
   types the text into the selected session's own terminal and presses Enter
   through the agent source's `Send`, as the orchestrate pill does. The field

internal/app/chat.go

@@ -117,6 +117,7 @@ func (f *Frame) attachChat(env view.Env, src agentstate.AgentSource) (stop func(
 	f.Chat = chatview.New(env, f.Session.StateDir, nil)
 	f.Chat.Worker = f.agentAt
 	f.Chat.Meta = f.chatMeta
+	f.Chat.NextPrompt = f.nextPrompt
 	f.Chat.Team = f.chatTeam
 	f.Chat.OpenNeeds = f.openNeeds
 	// The notch is made after the chat: it is read when the pinned prompt builds.

internal/app/chatview/chat.go

@@ -57,6 +57,11 @@ type Chat struct {
 	// Path gives the files and folders of the session at addr for the "@" popup (D279); nil
 	// shows none.
 	Path PathSource
+	// NextPrompt is Claude Code's suggested next prompt in the input line of the terminal at addr,
+	// "" for none (D281). It runs on the UI thread. Nil: the placeholder shows.
+	NextPrompt func(addr string) string
+	// next is the suggestion the composer shows in its empty field, for Tab.
+	next string
 	// sg is the state of the composer's suggestion popup.
 	sg suggest
 

internal/app/chatview/composer.go

@@ -8,6 +8,7 @@ import (
 	"strconv"
 	"strings"
 	"time"
+	"unicode/utf8"
 
 	"github.com/egoist/mygo/transfer"
 	"github.com/egoist/mygo/ui"
@@ -138,7 +139,14 @@ func (ch *Chat) composer(c *ui.Context, id string, st liveState) {
 				field = field.Margin(fieldGap, 0, 0, 0)
 			}
 			field.Children(func() {
-				in := ui.TextAreaBase(c.Key("composer:"+id), draft).Label(LabelComposer).Placeholder(Placeholder(ch.name(id))).
+				hint := Placeholder(ch.name(id))
+				if ch.next = ""; *draft == "" && ch.NextPrompt != nil {
+					// Claude Code's suggested next prompt takes the place of the placeholder (D281).
+					if ch.next = ch.NextPrompt(id); ch.next != "" {
+						hint = ch.next
+					}
+				}
+				in := ui.TextAreaBase(c.Key("composer:"+id), draft).Label(LabelComposer).Placeholder(hint).
 					PlaceholderColor(pal.Ink48).TextColor(pal.Ink100).FontSize(ct.Size).LineHeight(ct.Line/ct.Size).
 					Lines(1, composerLines).Grow(1).MinWidth(0).Padding((actionSize-ct.Line)/2, 0, (actionSize-ct.Line)/2, theme.Space6).AutoFocus().Bind(&ch.field).
 					OnTextKey(func(k ui.TextKey) bool { return ch.textKey(id, st, k) }).
@@ -261,13 +269,21 @@ func (ch *Chat) action(c *ui.Context, id string, st liveState, a Action) {
 	})
 }
 
-// textKey is a key of the field that types no text. Enter sends; ⇧Enter goes on to the field,
+// textKey is a key of the field that types no text. Tab or Right in an empty field takes the
+// suggested next prompt (D281). Enter sends; ⇧Enter goes on to the field,
 // which breaks the line. While the suggestion popup shows, it takes its keys first (D273). Esc interrupts the agent while it works and does nothing else: it closes
 // and switches nothing.
 func (ch *Chat) textKey(id string, st liveState, k ui.TextKey) bool {
 	if ch.suggestKey(id, k) {
 		return true
 	}
+	if (k.Key == ui.KeyTab || k.Key == ui.KeyRight) && k.Mods == 0 && ch.next != "" && k.Text() == "" {
+		// Tab or Right takes the suggested next prompt into the empty field (D281).
+		k.SetText(ch.next)
+		ch.sg.caret = utf8.RuneCountInString(ch.next)
+		ch.next = ""
+		return true
+	}
 	switch {
 	case k.Key == ui.KeyEnter && k.Mods == 0:
 		ch.submit(id, st, k.Text(), func() { k.SetText("") })

internal/app/chatview/composer_test.go

@@ -51,6 +51,16 @@ func newSession(t *testing.T, status string) *sess {
 	return s
 }
 
+// hint is the composer field's placeholder.
+func (s *sess) hint() string {
+	s.t.Helper()
+	a, ok := s.tt.Access(LabelComposer)
+	if !ok {
+		s.t.Fatal("no composer field")
+	}
+	return a.Placeholder
+}
+
 // typeIn types text into the composer, which has the focus.
 func (s *sess) typeIn(text string) {
 	s.t.Helper()
@@ -446,3 +456,60 @@ func (r *rig) footerWorks() bool {
 	}
 	return false
 }
+
+func TestComposerShowsTheNextPrompt(t *testing.T) {
+	s := newSession(t, "idle")
+	next := "commit this"
+	s.ch.NextPrompt = func(addr string) string {
+		if addr != term {
+			return ""
+		}
+		return next
+	}
+	s.tt.Frame()
+	if h := s.hint(); h != "commit this" {
+		t.Fatalf("the field shows %q, want the suggestion", h)
+	}
+	// Enter with an empty field sends nothing, as before.
+	s.key(0, ui.KeyEnter)
+	if len(s.sent) != 0 {
+		t.Errorf("Enter sent %v", s.sent)
+	}
+	// Tab takes it into the field.
+	s.key(0, ui.KeyTab)
+	if s.draft() != "commit this" {
+		t.Fatalf("Tab gave the draft %q", s.draft())
+	}
+	s.key(0, ui.KeyEnter)
+	if len(s.sent) != 1 || s.sent[0] != "commit this" {
+		t.Errorf("sent %v", s.sent)
+	}
+}
+
+func TestComposerTypingHidesTheNextPrompt(t *testing.T) {
+	s := newSession(t, "idle")
+	s.ch.NextPrompt = func(string) string { return "commit this" }
+	s.tt.Frame()
+	s.typeIn("x")
+	if h := s.hint(); h == "commit this" {
+		t.Errorf("the suggestion stays with text in the field")
+	}
+	// Tab with text in the field does not replace it.
+	s.key(0, ui.KeyTab)
+	if s.draft() != "x" {
+		t.Errorf("Tab changed the draft to %q", s.draft())
+	}
+}
+
+func TestComposerWithoutNextPromptShowsThePlaceholder(t *testing.T) {
+	s := newSession(t, "idle")
+	s.ch.NextPrompt = func(string) string { return "" }
+	s.tt.Frame()
+	if h := s.hint(); h != "Message lead…" {
+		t.Errorf("the field shows %q, want the placeholder", h)
+	}
+	s.key(0, ui.KeyTab)
+	if s.draft() != "" {
+		t.Errorf("Tab with no suggestion gave %q", s.draft())
+	}
+}

internal/app/chatview/sheet_test.go

@@ -180,18 +180,20 @@ type composerState struct {
 	team            *Team
 	text            string
 	h               float32
+	next            string // Claude Code's suggested next prompt (D281)
 }
 
 var composerStates = []composerState{
-	{"Idle, empty: no button, the keys in the footer", "idle", &Team{Agents: 2, Idle: 2}, "", 150},
-	{"Idle, text: Send", "idle", &Team{Agents: 2, Idle: 2}, "Merge #611 first, then tell b-632 to merge main.", 150},
-	{"Working, empty: Stop", "working", &Team{Agents: 2, NeedsYou: 1, Working: 1}, "", 150},
-	{"Working, text, no team: Working in the footer, Send (the message queues)", "working", nil, "And run the review on its exact head.", 150},
-	{"Many lines: the field grows to 8 lines, then scrolls", "idle", &Team{Agents: 2, Working: 2}, strings.TrimSuffix(strings.Repeat("A line of the message\n", 11), "\n"), 330},
-	{"No team, idle: the field alone", "idle", nil, "", 130},
+	{"Idle, empty: no button, the keys in the footer", "idle", &Team{Agents: 2, Idle: 2}, "", 150, ""},
+	{"Idle, text: Send", "idle", &Team{Agents: 2, Idle: 2}, "Merge #611 first, then tell b-632 to merge main.", 150, ""},
+	{"Working, empty: Stop", "working", &Team{Agents: 2, NeedsYou: 1, Working: 1}, "", 150, ""},
+	{"Working, text, no team: Working in the footer, Send (the message queues)", "working", nil, "And run the review on its exact head.", 150, ""},
+	{"Many lines: the field grows to 8 lines, then scrolls", "idle", &Team{Agents: 2, Working: 2}, strings.TrimSuffix(strings.Repeat("A line of the message\n", 11), "\n"), 330, ""},
+	{"No team, idle: the field alone", "idle", nil, "", 130, ""},
+	{"Idle, empty, a suggested next prompt: it takes the placeholder's place (D281)", "idle", nil, "", 130, "commit this and open a PR"},
 }
 
-const composerSheetH = 1230
+const composerSheetH = 1380
 
 // sheetComposer stacks the composer card in each of composerStates, each under its caption, at the
 // bottom of a short chat.
@@ -203,6 +205,9 @@ func sheetComposer(t *testing.T) func(c *ui.Context) {
 			teamOf(v, *st.team)
 		}
 		*v.s.ch.draft(term) = st.text
+		if next := st.next; next != "" {
+			v.s.ch.NextPrompt = func(string) string { return next }
+		}
 		views[i] = v
 	}
 	return func(c *ui.Context) {

internal/app/frame.go

@@ -12,6 +12,7 @@ import (
 	"os/exec"
 	"slices"
 	"sync"
+	"sync/atomic"
 	"time"
 
 	"github.com/egoist/mygo"
@@ -207,6 +208,10 @@ type Frame struct {
 	termSet   bool
 	termState ghostty.State
 	termErr   string
+	// next is the suggested next prompt read from the terminal at
+	// termAddr (D281); nextCheck is set while a read of it waits.
+	next      string
+	nextCheck atomic.Bool
 	// find is the find bar over the terminal (termfind.go).
 	find termFind
 	// hints tells when the key chips show: ⌘ held alone (docs/spec/KeyHints.md).
@@ -1120,6 +1125,7 @@ func (f *Frame) syncTerminal() {
 	}
 	f.closeTerminal()
 	f.resetFind()
+	f.next = ""
 	f.termAddr, f.termSet = addr, true
 	f.syncOutlineFocus()
 	f.termState, f.termErr = ghostty.State{Kind: ghostty.Connecting}, ""
@@ -1129,7 +1135,9 @@ func (f *Frame) syncTerminal() {
 	}
 	post, invalidate := f.post, f.invalidate
 	var conn *ghostty.Conn
-	conn = ghostty.NewConn(f.deps.TerminalSource(addr), ghostty.Options{Watch: true, OnState: func(s ghostty.State) {
+	var screen atomic.Pointer[gterm.Terminal]
+	onOutput := func() { f.checkNext(&screen, func() bool { return f.conn == conn }) }
+	conn = ghostty.NewConn(f.deps.TerminalSource(addr), ghostty.Options{Watch: true, OnOutput: onOutput, OnState: func(s ghostty.State) {
 		post(func() {
 			if f.conn == conn {
 				f.termState = s
@@ -1150,6 +1158,7 @@ func (f *Frame) syncTerminal() {
 		return
 	}
 	conn.SetScreen(t)
+	screen.Store(t)
 	f.term, f.conn = t, conn
 	f.autoFocus = !f.keyNav
 	f.setTerminalFocus(f.winFocused)

internal/app/ghostty/conn.go

@@ -86,6 +86,9 @@ type Options struct {
 	// OnState gets each change of the state, on any goroutine. It must not
 	// wait for the UI thread.
 	OnState func(State)
+	// OnOutput is called on the plugin's read goroutine as it takes output
+	// from the program. It must not wait for the UI thread. May be nil.
+	OnOutput func()
 	// Cols and Rows are the size of the first attach: 80 by 24 when zero.
 	// The view's size replaces it as soon as the view tells it.
 	Cols, Rows uint16
@@ -115,12 +118,13 @@ type chunk struct {
 // again with backoff and with Resumed, and holds what is typed meanwhile. Its
 // Read ends only when Close is called, so the plugin keeps its screen.
 type Conn struct {
-	src Source
-	on  func(State)
-	ctx context.Context
-	end context.CancelFunc
-	wg  sync.WaitGroup
-	out chan chunk // output and sizes from the pump to Read
+	src   Source
+	on    func(State)
+	onOut func() // Options.OnOutput
+	ctx   context.Context
+	end   context.CancelFunc
+	wg    sync.WaitGroup
+	out   chan chunk // output and sizes from the pump to Read
 
 	rmu sync.Mutex // Read's leftover
 	buf []byte
@@ -163,7 +167,7 @@ type Conn struct {
 // firstWait. Close ends it.
 func NewConn(src Source, o Options) *Conn {
 	ctx, end := context.WithCancel(context.Background())
-	c := &Conn{src: src, on: o.OnState, ctx: ctx, end: end, out: make(chan chunk),
+	c := &Conn{src: src, on: o.OnState, onOut: o.OnOutput, ctx: ctx, end: end, out: make(chan chunk),
 		visible: true, cols: o.Cols, rows: o.Rows, state: State{Kind: Connecting}, watching: o.Watch,
 		wake: make(chan struct{}, 1)}
 	if c.cols == 0 || c.rows == 0 {
@@ -232,6 +236,9 @@ func (c *Conn) Read(p []byte) (int, error) {
 				continue
 			}
 			c.buf = ch.data
+			if c.onOut != nil && len(ch.data) > 0 {
+				c.onOut()
+			}
 		case <-c.ctx.Done():
 			return 0, io.EOF
 		}

internal/app/ghostty/conn_test.go

@@ -5,6 +5,7 @@ import (
 	"errors"
 	"io"
 	"sync"
+	"sync/atomic"
 	"testing"
 	"time"
 
@@ -1314,3 +1315,20 @@ func TestWriteDropsSchemeReports(t *testing.T) {
 	}
 	waitAttaches(t, src, 2)
 }
+
+func TestOnOutputIsCalledForEachTakenOutput(t *testing.T) {
+	fast(t)
+	src := newFakeSource()
+	var n atomic.Int32
+	c := NewConn(src, Options{OnOutput: func() { n.Add(1) }})
+	t.Cleanup(func() { _ = c.Close() })
+	s := src.stream(t, 0)
+	s.data("hello ")
+	s.data("world")
+	if got := readN(t, c, 11); got != "hello world" {
+		t.Errorf("read %q", got)
+	}
+	if got := n.Load(); got != 2 {
+		t.Errorf("OnOutput called %d times, want 2", got)
+	}
+}