submit composer input via tmux server, not the detached client PTY

The composer sent input with pane.write, which writes to the PTY of the
tmux client the app spawned. That client detaches (we no longer render
or drain its PTY since T-137), leaving the session alive on the server
with no client — so keystrokes written to the dead PTY vanished and
Claude never saw the message.

Submit now goes through the tmux server: load the text into a named
paste buffer, paste it bracketed (multi-line and special chars arrive as
one block, not a stream of submits), then send Enter. Verified against a
live session — paste-buffer -p reaches Claude's input with no client
attached. The no-tmux fallback still uses pane.write (claude runs
directly in our PTY there).

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

.pql/changelog/ticket_history/2026-05.sql

@@ -2142,3 +2142,4 @@ Findings (2026-05-22): docs/spikes/cc-team-internals-2.1.148.md. All 5 checks an
 INSERT INTO ticket_history (ticket_id, field, old_value, new_value, changed_by, changed_at, created_at, updated_at, deleted_at, hash, canonical_version) VALUES ('T-137', 'status', 'backlog', 'in_progress', NULL, '2026-05-22 17:58:07', '2026-05-22 17:58:07', '2026-05-22 17:58:07', NULL, '4e67262d4b04f8541e71fe8f03106fbf', 1) ON CONFLICT(hash) DO NOTHING;
 INSERT INTO ticket_history (ticket_id, field, old_value, new_value, changed_by, changed_at, created_at, updated_at, deleted_at, hash, canonical_version) VALUES ('T-137', 'status', 'in_progress', 'done', NULL, '2026-05-22 18:14:32', '2026-05-22 18:14:32', '2026-05-22 18:14:32', NULL, 'a284c7249dda3c63a52a202bad07f105', 1) ON CONFLICT(hash) DO NOTHING;
 INSERT INTO ticket_history (ticket_id, field, old_value, new_value, changed_by, changed_at, created_at, updated_at, deleted_at, hash, canonical_version) VALUES ('T-138', 'status', 'backlog', 'in_progress', NULL, '2026-05-22 21:08:05', '2026-05-22 21:08:05', '2026-05-22 21:08:05', NULL, 'c3dfefe24d912081cd89ac0be066b641', 1) ON CONFLICT(hash) DO NOTHING;
+INSERT INTO ticket_history (ticket_id, field, old_value, new_value, changed_by, changed_at, created_at, updated_at, deleted_at, hash, canonical_version) VALUES ('T-138', 'status', 'in_progress', 'done', NULL, '2026-05-22 21:49:09', '2026-05-22 21:49:09', '2026-05-22 21:49:09', NULL, 'e4be02e339d638da70a4e7ce0f850691', 1) ON CONFLICT(hash) DO NOTHING;

.pql/changelog/tickets/2026-05.sql

@@ -2487,3 +2487,4 @@ Findings (2026-05-22): docs/spikes/cc-team-internals-2.1.148.md. All 5 checks an
 INSERT INTO tickets (id, type, parent_id, title, description, status, priority, assigned_to, team, decision_ref, created_at, updated_at, deleted_at, hash, canonical_version) VALUES ('T-137', 'story', 'T-132', 'ConversationView + replace the terminal in the Claude pane', 'New lib/builtin/claude/src/conversation_view.dart rendering user / assistant(markdown via ClideMarkdown) / tool-call card / tool-result+diff card; whole tree under one SelectionArea. Swap ClidePtyView -> ConversationView in lib/builtin/claude/src/claude_pane.dart (~line 287). Claude still runs in tmux (detached / output ignored) but content comes from the transcript (TranscriptReader). Keep the terminal builtin + ClidePtyView for general use. Surface conversation as events too (D-6). Cite D-75. Acceptance: make run shows the native Claude conversation from the live transcript; select+copy across cards works; no terminal in the Claude pane; terminal builtin still works; widget tests. Blocked by T3, T4.', 'in_progress', 'high', NULL, NULL, NULL, '2026-05-22 15:59:34', '2026-05-22 17:58:07', NULL, 'e8244b90386314574545f0c1a7bd012c', 1) ON CONFLICT(id) DO UPDATE SET type=excluded.type, parent_id=excluded.parent_id, title=excluded.title, description=excluded.description, status=excluded.status, priority=excluded.priority, assigned_to=excluded.assigned_to, team=excluded.team, decision_ref=excluded.decision_ref, updated_at=excluded.updated_at, deleted_at=excluded.deleted_at, hash=excluded.hash, canonical_version=excluded.canonical_version WHERE excluded.updated_at > tickets.updated_at OR (excluded.updated_at = tickets.updated_at AND excluded.hash > tickets.hash);
 INSERT INTO tickets (id, type, parent_id, title, description, status, priority, assigned_to, team, decision_ref, created_at, updated_at, deleted_at, hash, canonical_version) VALUES ('T-137', 'story', 'T-132', 'ConversationView + replace the terminal in the Claude pane', 'New lib/builtin/claude/src/conversation_view.dart rendering user / assistant(markdown via ClideMarkdown) / tool-call card / tool-result+diff card; whole tree under one SelectionArea. Swap ClidePtyView -> ConversationView in lib/builtin/claude/src/claude_pane.dart (~line 287). Claude still runs in tmux (detached / output ignored) but content comes from the transcript (TranscriptReader). Keep the terminal builtin + ClidePtyView for general use. Surface conversation as events too (D-6). Cite D-75. Acceptance: make run shows the native Claude conversation from the live transcript; select+copy across cards works; no terminal in the Claude pane; terminal builtin still works; widget tests. Blocked by T3, T4.', 'done', 'high', NULL, NULL, NULL, '2026-05-22 15:59:34', '2026-05-22 18:14:32', NULL, '6651a2c3c9099f7d38553f6cf9e41e98', 1) ON CONFLICT(id) DO UPDATE SET type=excluded.type, parent_id=excluded.parent_id, title=excluded.title, description=excluded.description, status=excluded.status, priority=excluded.priority, assigned_to=excluded.assigned_to, team=excluded.team, decision_ref=excluded.decision_ref, updated_at=excluded.updated_at, deleted_at=excluded.deleted_at, hash=excluded.hash, canonical_version=excluded.canonical_version WHERE excluded.updated_at > tickets.updated_at OR (excluded.updated_at = tickets.updated_at AND excluded.hash > tickets.hash);
 INSERT INTO tickets (id, type, parent_id, title, description, status, priority, assigned_to, team, decision_ref, created_at, updated_at, deleted_at, hash, canonical_version) VALUES ('T-138', 'task', 'T-132', 'Native composer + file/image paste', 'New lib/builtin/claude/src/claude_composer.dart: native text field -> tmux -L clide send-keys -t <pane> (Enter submit, Shift+Enter newline). Paste text inline; file/image per the T2 spike finding (likely temp-file + path/@-reference, since send-keys carries text only). Acceptance: typing in the composer reaches Claude; pasting a text file and an image both work via the validated mechanism. Blocked by T2, T5.', 'in_progress', 'medium', NULL, NULL, NULL, '2026-05-22 15:59:34', '2026-05-22 21:08:05', NULL, '2e6b932ad78ac78d83c86c5e08290ed3', 1) ON CONFLICT(id) DO UPDATE SET type=excluded.type, parent_id=excluded.parent_id, title=excluded.title, description=excluded.description, status=excluded.status, priority=excluded.priority, assigned_to=excluded.assigned_to, team=excluded.team, decision_ref=excluded.decision_ref, updated_at=excluded.updated_at, deleted_at=excluded.deleted_at, hash=excluded.hash, canonical_version=excluded.canonical_version WHERE excluded.updated_at > tickets.updated_at OR (excluded.updated_at = tickets.updated_at AND excluded.hash > tickets.hash);
+INSERT INTO tickets (id, type, parent_id, title, description, status, priority, assigned_to, team, decision_ref, created_at, updated_at, deleted_at, hash, canonical_version) VALUES ('T-138', 'task', 'T-132', 'Native composer + file/image paste', 'New lib/builtin/claude/src/claude_composer.dart: native text field -> tmux -L clide send-keys -t <pane> (Enter submit, Shift+Enter newline). Paste text inline; file/image per the T2 spike finding (likely temp-file + path/@-reference, since send-keys carries text only). Acceptance: typing in the composer reaches Claude; pasting a text file and an image both work via the validated mechanism. Blocked by T2, T5.', 'done', 'medium', NULL, NULL, NULL, '2026-05-22 15:59:34', '2026-05-22 21:49:09', NULL, '8b247ce6f9fc63c6f56030303aece2e8', 1) ON CONFLICT(id) DO UPDATE SET type=excluded.type, parent_id=excluded.parent_id, title=excluded.title, description=excluded.description, status=excluded.status, priority=excluded.priority, assigned_to=excluded.assigned_to, team=excluded.team, decision_ref=excluded.decision_ref, updated_at=excluded.updated_at, deleted_at=excluded.deleted_at, hash=excluded.hash, canonical_version=excluded.canonical_version WHERE excluded.updated_at > tickets.updated_at OR (excluded.updated_at = tickets.updated_at AND excluded.hash > tickets.hash);

CHANGELOG.md

@@ -19,9 +19,10 @@ heading, and (b) bumping `pubspec.yaml` `version:` in the same commit.
 ### Added
 
 - Native composer in the Claude pane (T-138) — type below the
-  conversation and press Enter to send (Shift+Enter for a newline);
-  input reaches Claude over `pane.write`. Multi-line text is sent as a
-  bracketed paste so it submits as one message.
+  conversation and press Enter to send (Shift+Enter for a newline).
+  Submits via the tmux server (bracketed paste + Enter), so input
+  reaches Claude even when no tmux client is attached; multi-line goes
+  as one message.
 - File and image paste in the composer (T-138) — Ctrl/Cmd+V of a copied
   file or a clipboard image inserts an `@path` reference (images are
   saved to a cache dir first); plain text pastes inline. Backed by a

lib/builtin/claude/src/claude_pane.dart

@@ -49,6 +49,7 @@ class _ClaudePaneState extends State<ClaudePane> {
   String _statusLine = 'attaching…';
 
   bool _spawned = false;
+  bool _usingTmux = false;
 
   @override
   void didChangeDependencies() {
@@ -193,8 +194,10 @@ class _ClaudePaneState extends State<ClaudePane> {
         setState(() => _error = resp.error?.message ?? 'spawn failed');
         return;
       }
+      _usingTmux = false;
       setState(() => _statusLine = 'no-tmux · fresh every launch');
     } else {
+      _usingTmux = true;
       setState(() => _statusLine = 'tmux · $_sessionName');
     }
 
@@ -213,10 +216,17 @@ class _ClaudePaneState extends State<ClaudePane> {
     setState(() {});
   }
 
-  // Send composed text to Claude's tmux session. pane.write delivers it
-  // to the PTY (the attached tmux client), which forwards to claude — the
-  // same input verb the terminal pane uses, so D-6 parity holds.
+  // Send composed text to Claude. On the tmux path, submit via the tmux
+  // server (paste-buffer + Enter) — it reaches Claude even with no client
+  // attached, unlike pane.write to the (now-detached) spawned client PTY.
+  // The no-tmux fallback runs claude directly in our PTY, where pane.write
+  // does reach it.
   void _send(String text) {
+    if (_usingTmux) {
+      final session = _sessionName;
+      if (session != null) unawaited(tmux.sendMessage(session, text));
+      return;
+    }
     final id = _paneId;
     final ipc = _ipc();
     if (id == null || ipc == null) return;

lib/builtin/claude/src/tmux_session.dart

@@ -54,3 +54,21 @@ Future<void> killAllForRepo(String primaryName) async {
     }
   }
 }
+
+/// Named tmux paste buffer clide loads composed messages into.
+const _composeBuffer = 'clide-compose';
+
+/// Submit [text] to [session] as a single message: load it into a named
+/// paste buffer, paste it in bracketed mode (so multi-line content and
+/// special characters arrive as one block rather than a stream of
+/// submits), then press Enter.
+///
+/// This goes through the tmux *server*, so it reaches Claude whether or
+/// not a client is attached. Writing to the app's spawned client PTY
+/// (`pane.write`) does not — once that client detaches, the PTY is dead
+/// and keystrokes vanish (the bug this replaces).
+Future<void> sendMessage(String session, String text) async {
+  await tmuxRunner([..._socket, 'set-buffer', '-b', _composeBuffer, '--', text]);
+  await tmuxRunner([..._socket, 'paste-buffer', '-p', '-d', '-b', _composeBuffer, '-t', session]);
+  await tmuxRunner([..._socket, 'send-keys', '-t', session, 'Enter']);
+}

test/builtin/claude/tmux_session_test.dart

@@ -103,4 +103,15 @@ void main() {
       ]);
     });
   });
+
+  group('sendMessage', () {
+    test('loads a bracketed paste buffer then submits with Enter', () async {
+      await tmux.sendMessage('clide-claude-foo', 'hello\nworld');
+      expect(runner.calls, [
+        ['-L', 'clide', 'set-buffer', '-b', 'clide-compose', '--', 'hello\nworld'],
+        ['-L', 'clide', 'paste-buffer', '-p', '-d', '-b', 'clide-compose', '-t', 'clide-claude-foo'],
+        ['-L', 'clide', 'send-keys', '-t', 'clide-claude-foo', 'Enter'],
+      ]);
+    });
+  });
 }