fix(session-goal): bound length recovery after truncation (#3278)

Thanks to alvins82 for tracing the truncation failure and to bashrusakh for adding bounded recovery and error precedence. We will finish the explicit Resume behavior in the same batch.

Closes #3255

Co-authored-by: alvins82 <alvins82@gmail.com>

packages/web/server/lib/session-goal/DOCUMENTATION.md

@@ -108,13 +108,23 @@ before touching the filesystem). Rationale: metadata rides every
      stop), with a tick-side safety net. Messages sent while paused leave
      the goal alone; Resume re-arms the loop, and resuming over an aborted
      tail skips the audit and goes straight to a continuation nudge;
-   - terminal checks, cheapest first: assistant turn error → `blocked`;
+    - terminal checks, cheapest first: assistant turn error → `blocked`;
-     `tokensUsed >= tokenBudget` → `budgetLimited`;
+      `tokensUsed >= tokenBudget` → `budgetLimited`;
-     `turnsUsed >= MAX_AUTO_TURNS` (20) → `blocked`;
+      `turnsUsed >= MAX_AUTO_TURNS` (20) → `blocked`;
-   - if the latest message is a compaction summary, skip the audit and
+    - error classification is independent of `finish`: `MessageAbortedError`
-     continue unconditionally — running into the context window mid-work is
+      keeps the pause/resume behavior; only a `finish: "length"` with no
-     by definition "in progress, not finished" (the summary is a retelling,
+      error, or `MessageOutputLengthError`, is an in-progress truncation that
-     not evidence, and must not be judged);
+      skips the audit and continues. Any other non-null error wins over a
+      length finish and blocks with its non-empty `error.name`, or
+      `assistant turn failed` when unnamed;
+    - length recovery is bounded separately from the token budget and
+      auto-continuation cap: the first truncation permits one continuation, but
+      a second consecutive completed, non-summary assistant turn that is also
+      truncated settles the goal as `blocked` (`repeated output truncation`).
+      The consecutive state is derived from the loaded message history, not
+      persisted, using `info.time.created` chronology rather than message IDs.
+      Summary messages are not agent turns; an ordinary completed assistant
+      turn naturally breaks the consecutive condition;
    - otherwise, small-model audit of the objective + the last assistant turn
      only — no conversation history and no continuation prompts
      (`restrictToPreferredProvider`, session's own provider/model preferred):

packages/web/server/lib/session-goal/runtime.js

@@ -244,6 +244,57 @@ const messageTokenTotal = (info) => {
   return input + cachedRead + output;
 };
 
+const getErrorName = (error) => error?.name?.trim?.() ?? '';
+
+const isLengthTruncated = (info, errorName = getErrorName(info?.error)) => {
+  const error = info?.error;
+  const hasError = error !== null && error !== undefined;
+  return errorName === 'MessageOutputLengthError' || (!hasError && info?.finish === 'length');
+};
+
+// Summary messages are assistant-shaped, but they are compaction turns rather
+// than agent turns. They must not break or satisfy the consecutive truncation
+// check; only completed, non-summary assistant turns participate. Chronology
+// comes from `time.created`, never from message IDs; array position is only a
+// tie-breaker for equal timestamps.
+const hasRepeatedLengthTail = (messages, latestAssistant, goalCreatedAt) => {
+  const latestInfo = latestAssistant?.info;
+  if (latestInfo?.summary === true) return false;
+  const latestIndex = messages.indexOf(latestAssistant);
+  const latestCreated = latestInfo?.time?.created;
+  if (
+    latestIndex < 0
+    || !(latestInfo?.time?.completed > 0)
+    || !(Number.isFinite(latestCreated) && latestCreated > 0)
+    || !isLengthTruncated(latestInfo)
+  ) return false;
+
+  let previous = null;
+  for (let i = 0; i < messages.length; i += 1) {
+    const info = messages[i]?.info;
+    if (info?.role !== 'assistant' || info.summary === true || !(info.time?.completed > 0)) continue;
+    const created = info.time?.created;
+    // An unknown timestamp cannot safely participate in chronology. Ignore it
+    // rather than letting an unrelated older message hide known chronology.
+    if (!(Number.isFinite(created) && created > 0)) continue;
+    if (i === latestIndex) continue;
+    if (created > latestCreated || (created === latestCreated && i > latestIndex)) continue;
+    if (
+      !previous
+      || created > previous.created
+      || (created === previous.created && i > previous.index)
+    ) {
+      previous = { info, created, index: i };
+    }
+  }
+
+  return Boolean(
+    previous
+    && previous.created > goalCreatedAt
+    && isLengthTruncated(previous.info),
+  );
+};
+
 export const createSessionGoalRuntime = ({
   buildOpenCodeUrl,
   getOpenCodeAuthHeaders,
@@ -609,7 +660,11 @@ export const createSessionGoalRuntime = ({
     // resumed over an aborted tail: that is an explicit "keep going", so it
     // falls through to the continuation below (skipping the audit — an
     // aborted reply is not evidence of anything).
-    const abortedTail = lastAssistantInfo.error?.name === 'MessageAbortedError';
+    const error = lastAssistantInfo.error;
+    const errorName = getErrorName(error);
+    const hasError = error !== null && error !== undefined;
+    const abortedTail = errorName === 'MessageAbortedError';
+    const lengthTail = isLengthTruncated(lastAssistantInfo, errorName);
     if (abortedTail && goal.statusReason !== 'resumed') {
       await writeGoal(sessionId, directory, goal.id, () => ({
         status: 'paused',
@@ -623,13 +678,12 @@ export const createSessionGoalRuntime = ({
       return;
     }
 
-    // Turn error → blocked (prevents runaway auto-continuation into failures).
+    // Non-length turn error → blocked (prevents runaway auto-continuation into
-    if (!abortedTail && lastAssistantInfo.error && typeof lastAssistantInfo.error === 'object') {
+    // failures). Recognized length cutoffs are in-progress continuations, not
-      const reason = typeof lastAssistantInfo.error.name === 'string' && lastAssistantInfo.error.name
+    // hard failures.
-        ? lastAssistantInfo.error.name
+    if (!abortedTail && !lengthTail && hasError) {
-        : 'assistant turn failed';
       await settleGoal({
-        sessionId, directory, goal, status: 'blocked', statusReason: reason, tokensUsed, tokensBaseline, tokensCommitted, lastAccountedMessageID,
+        sessionId, directory, goal, status: 'blocked', statusReason: errorName || 'assistant turn failed', tokensUsed, tokensBaseline, tokensCommitted, lastAccountedMessageID,
       });
       return;
     }
@@ -650,17 +704,28 @@ export const createSessionGoalRuntime = ({
       return;
     }
 
+    // A second consecutive completed, non-summary length-truncated turn is a
+    // bounded recovery failure. Derive this from the loaded transcript rather
+    // than persisting another goal counter.
+    if (lengthTail && hasRepeatedLengthTail(messages, lastAssistant, goal.createdAt)) {
+      await settleGoal({
+        sessionId, directory, goal, status: 'blocked', statusReason: 'repeated output truncation', tokensUsed, tokensBaseline, tokensCommitted, lastAccountedMessageID,
+      });
+      return;
+    }
+
     // --- Small-model audit: the sole termination authority besides the hard
     // stops above (turn error, budget, continuation cap). The working agent
     // has no channel to settle its own goal.
     //
-    // Exception: when the latest message is a compaction summary, the agent
+    // Exception: when the latest message is a compaction summary or was cut off
-    // by definition ran into the context window mid-work — that IS
+    // by the output token limit (length stop), the agent by definition ran into
-    // "in progress, not finished". No audit call; continue unconditionally.
+    // the context/output limit mid-work — that IS "in progress, not finished".
+    // No audit call; continue unconditionally.
     let audit = null;
     let blockedStreak = 0;
     let auditFailStreak = goal.auditFailStreak;
-    if (lastAssistantInfo.summary === true || abortedTail) {
+    if (lastAssistantInfo.summary === true || abortedTail || lengthTail) {
       blockedStreak = goal.blockedStreak;
     } else {
       audit = await runAudit({ goal: { ...goal, objective: effectiveObjective }, assistantText, directory, lastAssistantInfo: executionInfo ?? lastAssistantInfo });

packages/web/server/lib/session-goal/runtime.test.js

@@ -46,6 +46,75 @@ const startIdleTick = async (fetchImpl) => {
   return { runtime, getSmallModelService };
 };
 
+const assistantMessage = (id, infoOverrides = {}) => ({
+  info: {
+    id,
+    sessionID: SESSION_ID,
+    role: 'assistant',
+    providerID: 'provider',
+    modelID: 'model',
+    time: { created: 2, completed: 2 },
+    tokens: { input: 1, output: 1, cache: { read: 0 } },
+    ...infoOverrides,
+  },
+  parts: [{ type: 'text', text: 'The agent made progress.' }],
+});
+
+const createRuntimeHarness = ({ messages, messageFactory, goalOverrides = {}, maxAutoTurns = 20 }) => {
+  const requests = [];
+  let messageFetchCount = 0;
+  const activeSession = {
+    ...session,
+    metadata: { openchamber: { goal: { ...goal, ...goalOverrides } } },
+  };
+  const service = {
+    generateSmallModelText: vi.fn(async () => ({
+      text: '{"verdict":"continue","note":"More work remains"}',
+      providerID: 'provider',
+      modelID: 'model',
+    })),
+  };
+  const fetchImpl = vi.fn(async (input, init = {}) => {
+    const pathname = requestPath(input);
+    requests.push({ pathname, method: init.method ?? 'GET', body: init.body });
+    if (pathname === `/session/${SESSION_ID}` && init.method === 'PATCH') return jsonResponse(activeSession);
+    if (pathname === `/session/${SESSION_ID}`) return jsonResponse(activeSession);
+    if (pathname === '/session/status') return jsonResponse({});
+    if (pathname === `/session/${SESSION_ID}/children`) return jsonResponse([]);
+    if (pathname === `/session/${SESSION_ID}/message`) {
+      const nextMessages = messageFactory ? messageFactory(messageFetchCount) : messages;
+      messageFetchCount += 1;
+      return jsonResponse(nextMessages);
+    }
+    if (pathname === `/session/${SESSION_ID}/prompt_async`) return jsonResponse({ ok: true });
+    throw new Error(`Unexpected request: ${pathname}`);
+  });
+  vi.stubGlobal('fetch', fetchImpl);
+  const runtime = createSessionGoalRuntime({
+    buildOpenCodeUrl: (pathname) => `http://opencode.test${pathname}`,
+    getOpenCodeAuthHeaders: () => ({}),
+    getSmallModelService: async () => service,
+    isEnabled: () => true,
+    idleQuietMs: 10,
+    maxAutoTurns,
+  });
+  return { runtime, requests, service };
+};
+
+const runIdleTick = async (runtime) => {
+  runtime.processPayload({
+    type: 'session.status',
+    properties: { sessionID: SESSION_ID, status: { type: 'idle' }, directory: DIRECTORY },
+  });
+  await vi.runOnlyPendingTimersAsync();
+};
+
+const lastPatchedGoal = (requests) => {
+  const patches = requests.filter((request) => request.pathname === `/session/${SESSION_ID}` && request.method === 'PATCH');
+  expect(patches.length).toBeGreaterThan(0);
+  return JSON.parse(patches.at(-1).body).metadata.openchamber.goal;
+};
+
 describe('session goal live activity gate', () => {
   beforeEach(() => {
     vi.useFakeTimers();
@@ -178,4 +247,319 @@ describe('session goal live activity gate', () => {
     });
     runtime.stop();
   });
+
+  it('skips audit and sends continuation prompt when assistant message finishes with length stop', async () => {
+    const requests = [];
+    const fetchImpl = vi.fn(async (input, init = {}) => {
+      const pathname = requestPath(input);
+      requests.push({ pathname, method: init.method ?? 'GET', body: init.body });
+      if (pathname === `/session/${SESSION_ID}` && init.method === 'PATCH') return jsonResponse(session);
+      if (pathname === `/session/${SESSION_ID}`) return jsonResponse(session);
+      if (pathname === '/session/status') return jsonResponse({});
+      if (pathname === `/session/${SESSION_ID}/children`) return jsonResponse([]);
+      if (pathname === `/session/${SESSION_ID}/prompt_async`) return jsonResponse({ ok: true });
+      if (pathname === `/session/${SESSION_ID}/message`) {
+        return jsonResponse([{
+          info: {
+            id: 'msg_assistant_len',
+            sessionID: SESSION_ID,
+            role: 'assistant',
+            providerID: 'provider',
+            modelID: 'model',
+            finish: 'length',
+            time: { completed: 2 },
+            tokens: { input: 100, output: 4096, reasoning: 4096, cache: { read: 0 } },
+          },
+          parts: [{ type: 'reasoning', text: 'Drafting extensive implementation...' }],
+        }]);
+      }
+      throw new Error(`Unexpected request: ${pathname}`);
+    });
+    const service = {
+      generateSmallModelText: vi.fn(),
+    };
+    vi.stubGlobal('fetch', fetchImpl);
+    const runtime = createSessionGoalRuntime({
+      buildOpenCodeUrl: (pathname) => `http://opencode.test${pathname}`,
+      getOpenCodeAuthHeaders: () => ({}),
+      getSmallModelService: async () => service,
+      isEnabled: () => true,
+      idleQuietMs: 10,
+    });
+
+    runtime.processPayload({
+      type: 'session.status',
+      properties: { sessionID: SESSION_ID, status: { type: 'idle' }, directory: DIRECTORY },
+    });
+    await vi.runOnlyPendingTimersAsync();
+
+    // Audit must be skipped on length-truncated turn
+    expect(service.generateSmallModelText).not.toHaveBeenCalled();
+
+    // Goal accounting is persisted and turnsUsed incremented
+    const patch = requests.find((request) => request.pathname === `/session/${SESSION_ID}` && request.method === 'PATCH');
+    expect(patch).toBeDefined();
+    const writtenGoal = JSON.parse(patch.body).metadata.openchamber.goal;
+    expect(writtenGoal).toMatchObject({
+      status: 'active',
+      turnsUsed: 2,
+    });
+
+    // Continuation prompt is dispatched
+    const promptAsync = requests.find((request) => request.pathname === `/session/${SESSION_ID}/prompt_async` && request.method === 'POST');
+    expect(promptAsync).toBeDefined();
+    const promptBody = JSON.parse(promptAsync.body);
+    expect(promptBody.parts[0].text).toContain('Continue working toward the active session goal.');
+    runtime.stop();
+  });
+
+  it('skips audit and sends continuation prompt when assistant message carries MessageOutputLengthError', async () => {
+    const requests = [];
+    const fetchImpl = vi.fn(async (input, init = {}) => {
+      const pathname = requestPath(input);
+      requests.push({ pathname, method: init.method ?? 'GET', body: init.body });
+      if (pathname === `/session/${SESSION_ID}` && init.method === 'PATCH') return jsonResponse(session);
+      if (pathname === `/session/${SESSION_ID}`) return jsonResponse(session);
+      if (pathname === '/session/status') return jsonResponse({});
+      if (pathname === `/session/${SESSION_ID}/children`) return jsonResponse([]);
+      if (pathname === `/session/${SESSION_ID}/prompt_async`) return jsonResponse({ ok: true });
+      if (pathname === `/session/${SESSION_ID}/message`) {
+        return jsonResponse([{
+          info: {
+            id: 'msg_assistant_len_err',
+            sessionID: SESSION_ID,
+            role: 'assistant',
+            providerID: 'provider',
+            modelID: 'model',
+            error: { name: 'MessageOutputLengthError', message: 'Maximum token limit reached' },
+            time: { completed: 2 },
+            tokens: { input: 100, output: 4096, reasoning: 4096, cache: { read: 0 } },
+          },
+          parts: [{ type: 'reasoning', text: 'Drafting extensive implementation...' }],
+        }]);
+      }
+      throw new Error(`Unexpected request: ${pathname}`);
+    });
+    const service = {
+      generateSmallModelText: vi.fn(),
+    };
+    vi.stubGlobal('fetch', fetchImpl);
+    const runtime = createSessionGoalRuntime({
+      buildOpenCodeUrl: (pathname) => `http://opencode.test${pathname}`,
+      getOpenCodeAuthHeaders: () => ({}),
+      getSmallModelService: async () => service,
+      isEnabled: () => true,
+      idleQuietMs: 10,
+    });
+
+    runtime.processPayload({
+      type: 'session.status',
+      properties: { sessionID: SESSION_ID, status: { type: 'idle' }, directory: DIRECTORY },
+    });
+    await vi.runOnlyPendingTimersAsync();
+
+    // Audit must be skipped on MessageOutputLengthError
+    expect(service.generateSmallModelText).not.toHaveBeenCalled();
+
+    // Goal remains active and turnsUsed incremented
+    const patch = requests.find((request) => request.pathname === `/session/${SESSION_ID}` && request.method === 'PATCH');
+    expect(patch).toBeDefined();
+    const writtenGoal = JSON.parse(patch.body).metadata.openchamber.goal;
+    expect(writtenGoal).toMatchObject({
+      status: 'active',
+      turnsUsed: 2,
+    });
+
+    // Continuation prompt is dispatched
+    const promptAsync = requests.find((request) => request.pathname === `/session/${SESSION_ID}/prompt_async` && request.method === 'POST');
+    expect(promptAsync).toBeDefined();
+    runtime.stop();
+  });
+
+  it.each([
+    { name: 'APIError', error: { name: 'APIError', message: 'provider failed' } },
+    { name: 'StructuredOutputError', error: { name: 'StructuredOutputError', message: 'invalid output' } },
+    { name: 'unnamed errors', error: {} },
+  ])('blocks a length finish when the assistant also has a non-length $name', async ({ error }) => {
+    const { runtime, requests, service } = createRuntimeHarness({
+      messages: [assistantMessage('msg_assistant_error', { finish: 'length', error })],
+    });
+
+    await runIdleTick(runtime);
+
+    expect(service.generateSmallModelText).not.toHaveBeenCalled();
+    expect(requests.some((request) => request.pathname === `/session/${SESSION_ID}/prompt_async`)).toBe(false);
+    expect(lastPatchedGoal(requests)).toMatchObject({
+      status: 'blocked',
+      statusReason: error.name || 'assistant turn failed',
+    });
+    runtime.stop();
+  });
+
+  it('blocks after two consecutive length-truncated agent turns without persisting a counter, regardless of message IDs', async () => {
+    const firstLength = assistantMessage('z', { finish: 'length', time: { created: 10, completed: 11 } });
+    const summary = assistantMessage('summary', { summary: true, time: { created: 15, completed: 16 } });
+    const secondLength = assistantMessage('a', { finish: 'length', time: { created: 20, completed: 21 } });
+    const { runtime, requests, service } = createRuntimeHarness({
+      messageFactory: (fetchCount) => fetchCount < 2 ? [firstLength] : [firstLength, summary, secondLength],
+    });
+
+    await runIdleTick(runtime);
+    runtime.processPayload({
+      type: 'session.status',
+      properties: { sessionID: SESSION_ID, status: { type: 'idle' }, directory: DIRECTORY },
+    });
+    await vi.runOnlyPendingTimersAsync();
+
+    expect(service.generateSmallModelText).not.toHaveBeenCalled();
+    expect(requests.filter((request) => request.pathname === `/session/${SESSION_ID}/prompt_async`)).toHaveLength(1);
+    expect(lastPatchedGoal(requests)).toMatchObject({
+      status: 'blocked',
+      statusReason: 'repeated output truncation',
+    });
+    runtime.stop();
+  });
+
+  it('continues after a truncated agent turn followed by a length-finished summary', async () => {
+    const firstLength = assistantMessage('agent-length', { finish: 'length', time: { created: 10, completed: 11 } });
+    const summary = assistantMessage('summary', {
+      summary: true,
+      finish: 'length',
+      time: { created: 15, completed: 16 },
+    });
+    const { runtime, requests, service } = createRuntimeHarness({
+      messageFactory: (fetchCount) => fetchCount < 2 ? [firstLength] : [firstLength, summary],
+    });
+
+    await runIdleTick(runtime);
+    await runIdleTick(runtime);
+
+    expect(service.generateSmallModelText).not.toHaveBeenCalled();
+    expect(requests.filter((request) => request.pathname === `/session/${SESSION_ID}/prompt_async`)).toHaveLength(2);
+    expect(lastPatchedGoal(requests)).toMatchObject({ status: 'active' });
+    runtime.stop();
+  });
+
+  it('does not infer a repeated streak when a completed assistant timestamp is missing', async () => {
+    const firstLength = assistantMessage('z', { finish: 'length', time: { completed: 11 } });
+    const secondLength = assistantMessage('a', { finish: 'length', time: { created: 20, completed: 21 } });
+    const { runtime, requests, service } = createRuntimeHarness({
+      messageFactory: (fetchCount) => fetchCount < 2 ? [firstLength] : [firstLength, secondLength],
+    });
+
+    await runIdleTick(runtime);
+    await runIdleTick(runtime);
+
+    expect(service.generateSmallModelText).not.toHaveBeenCalled();
+    expect(requests.filter((request) => request.pathname === `/session/${SESSION_ID}/prompt_async`)).toHaveLength(2);
+    expect(lastPatchedGoal(requests)).toMatchObject({ status: 'active' });
+    runtime.stop();
+  });
+
+  it('ignores a missing timestamp on an older assistant when known post-goal turns establish a streak', async () => {
+    const olderLength = assistantMessage('legacy', { finish: 'length', time: { completed: 5 } });
+    const firstLength = assistantMessage('z', { finish: 'length', time: { created: 10, completed: 11 } });
+    const secondLength = assistantMessage('a', { finish: 'length', time: { created: 20, completed: 21 } });
+    const { runtime, requests, service } = createRuntimeHarness({
+      goalOverrides: { createdAt: 6 },
+      messageFactory: (fetchCount) => fetchCount < 2 ? [firstLength] : [olderLength, firstLength, secondLength],
+    });
+
+    await runIdleTick(runtime);
+    await runIdleTick(runtime);
+
+    expect(service.generateSmallModelText).not.toHaveBeenCalled();
+    expect(requests.filter((request) => request.pathname === `/session/${SESSION_ID}/prompt_async`)).toHaveLength(1);
+    expect(lastPatchedGoal(requests)).toMatchObject({
+      status: 'blocked',
+      statusReason: 'repeated output truncation',
+    });
+    runtime.stop();
+  });
+
+  it('does not count a previous truncated turn created at the goal boundary', async () => {
+    const firstLength = assistantMessage('before-boundary', { finish: 'length', time: { created: 10, completed: 11 } });
+    const secondLength = assistantMessage('after-boundary', { finish: 'length', time: { created: 20, completed: 21 } });
+    const { runtime, requests, service } = createRuntimeHarness({
+      goalOverrides: { createdAt: 10 },
+      messageFactory: (fetchCount) => fetchCount < 2 ? [firstLength] : [firstLength, secondLength],
+    });
+
+    await runIdleTick(runtime);
+    await runIdleTick(runtime);
+
+    expect(service.generateSmallModelText).not.toHaveBeenCalled();
+    expect(requests.filter((request) => request.pathname === `/session/${SESSION_ID}/prompt_async`)).toHaveLength(2);
+    expect(lastPatchedGoal(requests)).toMatchObject({ status: 'active' });
+    runtime.stop();
+  });
+
+  it('allows length recovery after an ordinary assistant turn breaks the streak', async () => {
+    const firstLength = assistantMessage('msg_length_before_normal', { finish: 'length' });
+    const normal = assistantMessage('msg_normal');
+    const secondLength = assistantMessage('msg_length_after_normal', { finish: 'length' });
+    const { runtime, requests, service } = createRuntimeHarness({
+      messageFactory: (fetchCount) => fetchCount < 2
+        ? [firstLength]
+        : [firstLength, normal, secondLength],
+    });
+
+    await runIdleTick(runtime);
+    await runIdleTick(runtime);
+
+    expect(service.generateSmallModelText).not.toHaveBeenCalled();
+    expect(requests.filter((request) => request.pathname === `/session/${SESSION_ID}/prompt_async`)).toHaveLength(2);
+    expect(lastPatchedGoal(requests)).toMatchObject({ status: 'active' });
+    runtime.stop();
+  });
+
+  it('keeps MessageAbortedError pause behavior instead of continuing', async () => {
+    const { runtime, requests, service } = createRuntimeHarness({
+      messages: [assistantMessage('msg_aborted', { error: { name: 'MessageAbortedError' } })],
+    });
+
+    await runIdleTick(runtime);
+
+    expect(service.generateSmallModelText).not.toHaveBeenCalled();
+    expect(requests.some((request) => request.pathname === `/session/${SESSION_ID}/prompt_async`)).toBe(false);
+    expect(lastPatchedGoal(requests)).toMatchObject({
+      status: 'paused',
+      statusReason: 'paused after abort',
+    });
+    runtime.stop();
+  });
+
+  it('checks the token budget before allowing length recovery', async () => {
+    const { runtime, requests, service } = createRuntimeHarness({
+      goalOverrides: { tokenBudget: 5 },
+      messages: [assistantMessage('msg_budget_length', {
+        finish: 'length',
+        tokens: { input: 3, output: 3, cache: { read: 0 } },
+      })],
+    });
+
+    await runIdleTick(runtime);
+
+    expect(service.generateSmallModelText).not.toHaveBeenCalled();
+    expect(requests.some((request) => request.pathname === `/session/${SESSION_ID}/prompt_async`)).toBe(false);
+    expect(lastPatchedGoal(requests)).toMatchObject({ status: 'budgetLimited' });
+    runtime.stop();
+  });
+
+  it('checks the auto-continuation cap before allowing length recovery', async () => {
+    const { runtime, requests, service } = createRuntimeHarness({
+      maxAutoTurns: 1,
+      messages: [assistantMessage('msg_cap_length', { finish: 'length' })],
+    });
+
+    await runIdleTick(runtime);
+
+    expect(service.generateSmallModelText).not.toHaveBeenCalled();
+    expect(requests.some((request) => request.pathname === `/session/${SESSION_ID}/prompt_async`)).toBe(false);
+    expect(lastPatchedGoal(requests)).toMatchObject({
+      status: 'blocked',
+      statusReason: 'auto-continuation limit reached',
+    });
+    runtime.stop();
+  });
 });