fix(paired): cap consecutive reviewer silent-failure retries

The reviewer (codex) sometimes emits a final result with no visible text.
The runtime marks the run failed → handleFailedReviewerExecution
preserves status as review_ready → the follow-up scheduler re-queues
another reviewer-turn → loop. The existing round_trip / arbiter caps
never fire because round_trip_count only advances on owner-side
submissions; bot-side reviewer flakes never increment it.

Mirror the owner_failure_count pattern: add reviewer_failure_count to
paired_tasks, increment on each silent failure, and escalate via
requestArbiterOrEscalate once it reaches 2. Reset to 0 on every
successful reviewer completion path (PROCEED/REVISE/arbiter/wait-for-user)
and when the owner re-submits a fresh review cycle.

Repro chat: 1507762222724546560 (stock-adiviser). Task
33968d31-0da2-480c-85d3-7a3999822ab4 logged 11 consecutive
reviewer-turn entries with no work_items and round_trip_count stuck
at 1.

src/db/base-schema.ts

@@ -121,6 +121,7 @@ export function applyBaseSchema(database: Database): void {
       review_requested_at TEXT,
       round_trip_count INTEGER NOT NULL DEFAULT 0,
       owner_failure_count INTEGER NOT NULL DEFAULT 0,
+      reviewer_failure_count INTEGER NOT NULL DEFAULT 0,
       owner_step_done_streak INTEGER NOT NULL DEFAULT 0,
       finalize_step_done_count INTEGER NOT NULL DEFAULT 0,
       task_done_then_user_reopen_count INTEGER NOT NULL DEFAULT 0,

src/db/bootstrap.test.ts

@@ -39,6 +39,7 @@ function getExpectedSchemaMigrations(): Array<{
     { version: 12, name: 'paired_verdict_and_step_telemetry' },
     { version: 13, name: 'message_source_kind' },
     { version: 14, name: 'work_item_attachments' },
+    { version: 15, name: 'reviewer_failure_count' },
   ];
 }
 

src/db/migrations/015_reviewer-failure-count.ts

@@ -0,0 +1,23 @@
+import type { Database } from 'bun:sqlite';
+
+import { tableHasColumn } from './helpers.js';
+import type { SchemaMigrationDefinition } from './types.js';
+
+export const REVIEWER_FAILURE_COUNT_MIGRATION: SchemaMigrationDefinition = {
+  version: 15,
+  name: 'reviewer_failure_count',
+  apply(database: Database) {
+    if (!tableHasColumn(database, 'paired_tasks', 'reviewer_failure_count')) {
+      database.exec(`
+        ALTER TABLE paired_tasks
+        ADD COLUMN reviewer_failure_count INTEGER NOT NULL DEFAULT 0
+      `);
+    }
+
+    database.exec(`
+      UPDATE paired_tasks
+         SET reviewer_failure_count = 0
+       WHERE reviewer_failure_count IS NULL
+    `);
+  },
+};

src/db/migrations/index.ts

@@ -14,6 +14,7 @@ import { OWNER_FAILURE_COUNT_MIGRATION } from './011_owner-failure-count.js';
 import { PAIRED_VERDICT_AND_STEP_TELEMETRY_MIGRATION } from './012_paired-verdict-and-step-telemetry.js';
 import { MESSAGE_SOURCE_KIND_MIGRATION } from './013_message-source-kind.js';
 import { WORK_ITEM_ATTACHMENTS_MIGRATION } from './014_work-item-attachments.js';
+import { REVIEWER_FAILURE_COUNT_MIGRATION } from './015_reviewer-failure-count.js';
 import type {
   SchemaMigrationArgs,
   SchemaMigrationDefinition,
@@ -36,6 +37,7 @@ const ORDERED_SCHEMA_MIGRATIONS: readonly SchemaMigrationDefinition[] = [
   PAIRED_VERDICT_AND_STEP_TELEMETRY_MIGRATION,
   MESSAGE_SOURCE_KIND_MIGRATION,
   WORK_ITEM_ATTACHMENTS_MIGRATION,
+  REVIEWER_FAILURE_COUNT_MIGRATION,
 ];
 
 function ensureSchemaMigrationsTable(database: Database): void {

src/db/paired-state.ts

@@ -51,6 +51,7 @@ export type PairedTaskUpdates = Partial<
     | 'review_requested_at'
     | 'round_trip_count'
     | 'owner_failure_count'
+    | 'reviewer_failure_count'
     | 'owner_step_done_streak'
     | 'finalize_step_done_count'
     | 'task_done_then_user_reopen_count'
@@ -177,6 +178,7 @@ export function createPairedTaskInDatabase(
           review_requested_at,
           round_trip_count,
           owner_failure_count,
+          reviewer_failure_count,
           owner_step_done_streak,
           finalize_step_done_count,
           task_done_then_user_reopen_count,
@@ -188,7 +190,7 @@ export function createPairedTaskInDatabase(
           created_at,
           updated_at
         )
-        VALUES (?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?)
+        VALUES (?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?)
       `,
     )
     .run(
@@ -206,6 +208,7 @@ export function createPairedTaskInDatabase(
       task.review_requested_at,
       task.round_trip_count,
       task.owner_failure_count ?? 0,
+      task.reviewer_failure_count ?? 0,
       task.owner_step_done_streak ?? 0,
       task.finalize_step_done_count ?? 0,
       task.task_done_then_user_reopen_count ?? 0,
@@ -318,6 +321,10 @@ export function updatePairedTaskInDatabase(
     fields.push('owner_failure_count = ?');
     values.push(updates.owner_failure_count);
   }
+  if (updates.reviewer_failure_count !== undefined) {
+    fields.push('reviewer_failure_count = ?');
+    values.push(updates.reviewer_failure_count);
+  }
   if (updates.owner_step_done_streak !== undefined) {
     fields.push('owner_step_done_streak = ?');
     values.push(updates.owner_step_done_streak);
@@ -397,6 +404,10 @@ export function updatePairedTaskIfUnchangedInDatabase(
     fields.push('owner_failure_count = ?');
     values.push(updates.owner_failure_count);
   }
+  if (updates.reviewer_failure_count !== undefined) {
+    fields.push('reviewer_failure_count = ?');
+    values.push(updates.reviewer_failure_count);
+  }
   if (updates.owner_step_done_streak !== undefined) {
     fields.push('owner_step_done_streak = ?');
     values.push(updates.owner_step_done_streak);

src/paired-execution-context-owner.ts

@@ -319,6 +319,7 @@ function maybeAutoTriggerReviewerAfterOwnerCompletion(args: {
       patch: {
         round_trip_count: task.round_trip_count + 1,
         owner_failure_count: 0,
+        reviewer_failure_count: 0,
         owner_step_done_streak: 0,
         empty_step_done_streak: 0,
         ...args.patch,

src/paired-execution-context-reviewer.ts

@@ -2,6 +2,7 @@ import { ARBITER_DEADLOCK_THRESHOLD, isArbiterEnabled } from './config.js';
 import { getPairedWorkspace } from './db.js';
 import { logger } from './logger.js';
 import {
+  applyPairedTaskPatch,
   parseReviewerVisibleVerdict,
   isUserInputWaitVerdict,
   requestArbiterOrEscalate,
@@ -12,6 +13,17 @@ import {
 } from './paired-execution-context-shared.js';
 import type { PairedTask } from './types.js';
 
+/**
+ * Maximum consecutive reviewer executions that may produce no verdict
+ * before we stop the ping-pong loop. Mirrors `OWNER_FAILURE_ESCALATION_THRESHOLD`
+ * on the owner side and closes the "reviewer silently fails forever" hole:
+ * codex sometimes emits a final result with no visible text, the runtime
+ * marks it failed, the next-turn scheduler re-queues another reviewer-turn,
+ * and the original round_trip_count never increments — so the existing
+ * round-trip / arbiter caps never fire.
+ */
+const REVIEWER_FAILURE_ESCALATION_THRESHOLD = 2;
+
 function isReviewerUnavailableFailure(summary: string | null | undefined) {
   return /(?:\b429\b|usage limit|rate limit|try again at|purchase more credits)/i.test(
     summary ?? '',
@@ -96,6 +108,35 @@ export function handleFailedReviewerExecution(args: {
     return;
   }
 
+  // Reviewer produced no usable verdict and no recognised infrastructure
+  // failure. Track consecutive flakes — after the threshold, stop the
+  // ping-pong loop instead of preserving review_ready forever.
+  const nextFailureCount = (task.reviewer_failure_count ?? 0) + 1;
+
+  if (nextFailureCount >= REVIEWER_FAILURE_ESCALATION_THRESHOLD) {
+    requestArbiterOrEscalate({
+      taskId,
+      currentStatus: task.status,
+      expectedUpdatedAt: task.updated_at,
+      now,
+      arbiterLogMessage:
+        'Reviewer failed repeatedly without a visible verdict — requesting arbiter',
+      escalateLogMessage:
+        'Reviewer failed repeatedly without a visible verdict — escalating to user',
+      logContext: {
+        taskId,
+        role: 'reviewer',
+        previousStatus: task.status,
+        reviewerFailureCount: nextFailureCount,
+        summary: summary?.slice(0, 160),
+      },
+      patch: {
+        reviewer_failure_count: nextFailureCount,
+      },
+    });
+    return;
+  }
+
   const fallbackStatus =
     task.status === 'in_review' || task.status === 'review_ready'
       ? 'review_ready'
@@ -107,17 +148,30 @@ export function handleFailedReviewerExecution(args: {
       nextStatus: fallbackStatus,
       expectedUpdatedAt: task.updated_at,
       updatedAt: now,
-    });
+      patch: {
-    logger.warn(
+        reviewer_failure_count: nextFailureCount,
-      {
-        taskId,
-        role: 'reviewer',
-        previousStatus: task.status,
-        nextStatus: fallbackStatus,
       },
-      'Preserved reviewer task in review-ready state after failed execution',
+    });
-    );
+  } else {
+    applyPairedTaskPatch({
+      taskId,
+      expectedUpdatedAt: task.updated_at,
+      updatedAt: now,
+      patch: {
+        reviewer_failure_count: nextFailureCount,
+      },
+    });
   }
+  logger.warn(
+    {
+      taskId,
+      role: 'reviewer',
+      previousStatus: task.status,
+      reviewerFailureCount: nextFailureCount,
+      summary: summary?.slice(0, 160),
+    },
+    'Preserved reviewer task in review-ready state after failed execution',
+  );
 }
 
 export function handleReviewerCompletion(args: {
@@ -141,6 +195,7 @@ export function handleReviewerCompletion(args: {
       updatedAt: now,
       patch: {
         completion_reason: 'escalated',
+        reviewer_failure_count: 0,
       },
     });
     logger.info(
@@ -170,6 +225,7 @@ export function handleReviewerCompletion(args: {
         updatedAt: now,
         patch: {
           source_ref: approvedSourceRef,
+          reviewer_failure_count: 0,
         },
       });
       logger.info(
@@ -201,6 +257,9 @@ export function handleReviewerCompletion(args: {
         arbiterLogMessage,
         escalateLogMessage,
         logContext: { taskId, verdict, summary: summary?.slice(0, 100) },
+        patch: {
+          reviewer_failure_count: 0,
+        },
       });
       return;
 
@@ -211,6 +270,9 @@ export function handleReviewerCompletion(args: {
         nextStatus: 'active',
         expectedUpdatedAt: task.updated_at,
         updatedAt: now,
+        patch: {
+          reviewer_failure_count: 0,
+        },
       });
       logger.info(
         { taskId, verdict },

src/paired-execution-context-shared.ts

@@ -270,6 +270,7 @@ export function transitionPairedTaskStatus(args: {
     review_requested_at?: string | null;
     round_trip_count?: number;
     owner_failure_count?: number;
+    reviewer_failure_count?: number;
     owner_step_done_streak?: number;
     finalize_step_done_count?: number;
     task_done_then_user_reopen_count?: number;
@@ -318,6 +319,7 @@ export function applyPairedTaskPatch(args: {
     review_requested_at?: string | null;
     round_trip_count?: number;
     owner_failure_count?: number;
+    reviewer_failure_count?: number;
     owner_step_done_streak?: number;
     finalize_step_done_count?: number;
     task_done_then_user_reopen_count?: number;
@@ -363,6 +365,7 @@ export function requestArbiterOrEscalate(args: {
     review_requested_at?: string | null;
     round_trip_count?: number;
     owner_failure_count?: number;
+    reviewer_failure_count?: number;
     owner_step_done_streak?: number;
     finalize_step_done_count?: number;
     task_done_then_user_reopen_count?: number;

src/paired-execution-context.test.ts

@@ -143,6 +143,7 @@ function buildPairedTask(overrides: Partial<PairedTask> = {}): PairedTask {
     review_requested_at: null,
     round_trip_count: 0,
     owner_failure_count: 0,
+    reviewer_failure_count: 0,
     owner_step_done_streak: 0,
     finalize_step_done_count: 0,
     task_done_then_user_reopen_count: 0,
@@ -1443,7 +1444,7 @@ describe('paired execution context', () => {
     );
   });
 
-  it('keeps reviewer tasks review_ready when reviewer execution fails without a terminal verdict', () => {
+  it('keeps reviewer tasks review_ready and increments reviewer_failure_count after the first silent failure', () => {
     vi.mocked(db.getPairedTaskById).mockReturnValue(
       buildPairedTask({
         status: 'in_review',
@@ -1461,11 +1462,38 @@ describe('paired execution context', () => {
       'task-1',
       expect.objectContaining({
         status: 'review_ready',
+        reviewer_failure_count: 1,
         updated_at: expect.any(String),
       }),
     );
   });
 
+  it('requests arbiter after repeated reviewer execution failures without a visible verdict', () => {
+    vi.spyOn(config, 'isArbiterEnabled').mockReturnValue(true);
+    vi.mocked(db.getPairedTaskById).mockReturnValue(
+      buildPairedTask({
+        status: 'review_ready',
+        reviewer_failure_count: 1,
+      }),
+    );
+
+    completePairedExecutionContext({
+      taskId: 'task-1',
+      role: 'reviewer',
+      status: 'failed',
+      summary: 'runtime exploded before verdict',
+    });
+
+    expect(db.updatePairedTask).toHaveBeenCalledWith(
+      'task-1',
+      expect.objectContaining({
+        status: 'arbiter_requested',
+        reviewer_failure_count: 2,
+        arbiter_requested_at: expect.any(String),
+      }),
+    );
+  });
+
   it('escalates reviewer usage-limit failures instead of retrying forever', () => {
     vi.mocked(db.getPairedTaskById).mockReturnValue(
       buildPairedTask({

src/paired-execution-context.ts

@@ -147,6 +147,7 @@ function createActiveTaskForRoom(args: {
     review_requested_at: null,
     round_trip_count: 0,
     owner_failure_count: 0,
+    reviewer_failure_count: 0,
     owner_step_done_streak: 0,
     finalize_step_done_count: 0,
     task_done_then_user_reopen_count: 0,
@@ -476,6 +477,7 @@ export function preparePairedExecutionContext(args: {
               ? {
                   round_trip_count: 0,
                   owner_failure_count: 0,
+                  reviewer_failure_count: 0,
                   owner_step_done_streak: 0,
                   empty_step_done_streak: 0,
                 }
@@ -492,6 +494,7 @@ export function preparePairedExecutionContext(args: {
               ? {
                   round_trip_count: 0,
                   owner_failure_count: 0,
+                  reviewer_failure_count: 0,
                   owner_step_done_streak: 0,
                   empty_step_done_streak: 0,
                 }

src/types.ts

@@ -124,6 +124,7 @@ export interface PairedTask {
   review_requested_at: string | null;
   round_trip_count: number;
   owner_failure_count?: number | null;
+  reviewer_failure_count?: number | null;
   owner_step_done_streak?: number | null;
   finalize_step_done_count?: number | null;
   task_done_then_user_reopen_count?: number | null;