fix: headless mode exits early on progress notifications containing 'complete' (#879) (#888)

isTerminalNotification() used broad substring matching against
['complete', 'stopped', 'blocked']. Any notification containing these
words triggered early exit — including progress messages like:
  'All slices are complete — nothing to discuss.'
  'Override(s) resolved — rewrite-docs completed.'
  'Skipped 5+ completed units. Yielding to UI before continuing.'

Fix: Replace substring matching with prefix matching against the actual
stop signals emitted by stopAuto():
  'Auto-mode stopped...'
  'Step-mode stopped...'

These are the ONLY notifications that indicate auto-mode has genuinely
terminated. All other notifications (slice completion, override
resolution, skip yielding) are progress events and must not trigger
exit.

Also tighten isBlockedNotification to match 'blocked:' (with colon)
instead of bare 'blocked' to avoid false positives from unrelated
messages.

Added 15 regression tests covering:
- All real terminal notification variants
- 6 false-positive cases from the issue report
- Non-notify event rejection
- Blocked detection with and without colon

src/headless.ts

@@ -188,7 +188,20 @@ function formatProgress(event: Record<string, unknown>, verbose: boolean): strin
 // Completion Detection
 // ---------------------------------------------------------------------------
 
-const TERMINAL_KEYWORDS = ['complete', 'stopped', 'blocked']
+/**
+ * Detect genuine auto-mode termination notifications.
+ *
+ * Only matches the actual stop signals emitted by stopAuto():
+ *   "Auto-mode stopped..."
+ *   "Step-mode stopped..."
+ *
+ * Does NOT match progress notifications that happen to contain words like
+ * "complete" or "stopped" (e.g., "Override resolved — rewrite-docs completed",
+ * "All slices are complete — nothing to discuss", "Skipped 5+ completed units").
+ *
+ * Blocked detection is separate — checked via isBlockedNotification.
+ */
+const TERMINAL_PREFIXES = ['auto-mode stopped', 'step-mode stopped']
 const IDLE_TIMEOUT_MS = 15_000
 // new-milestone is a long-running creative task where the LLM may pause
 // between tool calls (e.g. after mkdir, before writing files). Use a
@@ -198,12 +211,14 @@ const NEW_MILESTONE_IDLE_TIMEOUT_MS = 120_000
 function isTerminalNotification(event: Record<string, unknown>): boolean {
   if (event.type !== 'extension_ui_request' || event.method !== 'notify') return false
   const message = String(event.message ?? '').toLowerCase()
-  return TERMINAL_KEYWORDS.some((kw) => message.includes(kw))
+  return TERMINAL_PREFIXES.some((prefix) => message.startsWith(prefix))
 }
 
 function isBlockedNotification(event: Record<string, unknown>): boolean {
   if (event.type !== 'extension_ui_request' || event.method !== 'notify') return false
-  return String(event.message ?? '').toLowerCase().includes('blocked')
+  const message = String(event.message ?? '').toLowerCase()
+  // Blocked notifications come through stopAuto as "Auto-mode stopped (Blocked: ...)"
+  return message.includes('blocked:')
 }
 
 function isMilestoneReadyNotification(event: Record<string, unknown>): boolean {

src/tests/headless-detection.test.ts

@@ -0,0 +1,101 @@
+/**
+ * Tests for headless completion detection.
+ *
+ * Verifies that isTerminalNotification only matches actual auto-mode stop
+ * signals and does not false-positive on progress notifications that
+ * happen to contain words like "complete" or "stopped".
+ */
+
+import test from "node:test";
+import assert from "node:assert/strict";
+
+// Import the module to get access to the functions via a dynamic import
+// since headless.ts has side-effect-free detection functions but no exports.
+// We'll test by extracting the logic inline.
+
+// ─── Extracted detection logic (mirrors headless.ts) ────────────────────────
+
+const TERMINAL_PREFIXES = ['auto-mode stopped', 'step-mode stopped']
+
+function isTerminalNotification(event: Record<string, unknown>): boolean {
+  if (event.type !== 'extension_ui_request' || event.method !== 'notify') return false
+  const message = String(event.message ?? '').toLowerCase()
+  return TERMINAL_PREFIXES.some((prefix) => message.startsWith(prefix))
+}
+
+function isBlockedNotification(event: Record<string, unknown>): boolean {
+  if (event.type !== 'extension_ui_request' || event.method !== 'notify') return false
+  const message = String(event.message ?? '').toLowerCase()
+  return message.includes('blocked:')
+}
+
+function makeNotify(message: string): Record<string, unknown> {
+  return { type: 'extension_ui_request', method: 'notify', message }
+}
+
+// ─── isTerminalNotification ─────────────────────────────────────────────────
+
+test("detects 'Auto-mode stopped.' as terminal", () => {
+  assert.ok(isTerminalNotification(makeNotify("Auto-mode stopped.")))
+})
+
+test("detects 'Auto-mode stopped (All milestones complete).' as terminal", () => {
+  assert.ok(isTerminalNotification(makeNotify("Auto-mode stopped (All milestones complete). Session: $0.42 · 15K tokens · 8 units")))
+})
+
+test("detects 'Auto-mode stopped (Blocked: missing API key).' as terminal", () => {
+  assert.ok(isTerminalNotification(makeNotify("Auto-mode stopped (Blocked: missing API key).")))
+})
+
+test("detects 'Auto-mode stopped (Milestone M001 complete).' as terminal", () => {
+  assert.ok(isTerminalNotification(makeNotify("Auto-mode stopped (Milestone M001 complete).")))
+})
+
+test("detects 'Step-mode stopped.' as terminal", () => {
+  assert.ok(isTerminalNotification(makeNotify("Step-mode stopped.")))
+})
+
+// ─── False positives that previously triggered early exit (#879) ────────────
+
+test("does NOT match 'All slices are complete — nothing to discuss.'", () => {
+  assert.ok(!isTerminalNotification(makeNotify("All slices are complete — nothing to discuss.")))
+})
+
+test("does NOT match 'Override(s) resolved — rewrite-docs completed.'", () => {
+  assert.ok(!isTerminalNotification(makeNotify("Override(s) resolved — rewrite-docs completed.")))
+})
+
+test("does NOT match 'Skipped 5+ completed units. Yielding to UI before continuing.'", () => {
+  assert.ok(!isTerminalNotification(makeNotify("Skipped 5+ completed units. Yielding to UI before continuing.")))
+})
+
+test("does NOT match 'Cannot dispatch reassess-roadmap: no completed slices.'", () => {
+  assert.ok(!isTerminalNotification(makeNotify("Cannot dispatch reassess-roadmap: no completed slices.")))
+})
+
+test("does NOT match 'Committed: feat(S03): complete task implementation'", () => {
+  assert.ok(!isTerminalNotification(makeNotify("Committed: feat(S03): complete task implementation")))
+})
+
+test("does NOT match 'Post-hook: applied 3 fix(es).'", () => {
+  assert.ok(!isTerminalNotification(makeNotify("Post-hook: applied 3 fix(es).")))
+})
+
+test("does NOT match non-notify events", () => {
+  assert.ok(!isTerminalNotification({ type: 'agent_end' }))
+  assert.ok(!isTerminalNotification({ type: 'extension_ui_request', method: 'select', message: 'Auto-mode stopped.' }))
+})
+
+// ─── isBlockedNotification ──────────────────────────────────────────────────
+
+test("detects blocked notification with 'Blocked:' prefix", () => {
+  assert.ok(isBlockedNotification(makeNotify("Auto-mode stopped (Blocked: missing API key).")))
+})
+
+test("detects inline 'Blocked:' message", () => {
+  assert.ok(isBlockedNotification(makeNotify("Blocked: no active milestone. Fix and run /gsd auto.")))
+})
+
+test("does NOT match 'blocked' without colon (avoids false positives)", () => {
+  assert.ok(!isBlockedNotification(makeNotify("The request was blocked by the firewall")))
+})