diff --git a/packages/replay-test/src/internal/__tests__/session-test-runtime.test.ts b/packages/replay-test/src/internal/__tests__/session-test-runtime.test.ts
index 1a45bb36f..60481798a 100644
--- a/packages/replay-test/src/internal/__tests__/session-test-runtime.test.ts
+++ b/packages/replay-test/src/internal/__tests__/session-test-runtime.test.ts
@@ -154,6 +154,33 @@ test('runReplayTestAttempt keeps a passing replay passed when finalization fails
   expect(cleanupSession).toHaveBeenCalledWith('default:test:pass');
 });
 
+test('runReplayTestAttempt marks a failed cleanup as infrastructure so the scheduler cannot retry into its session', async () => {
+  const cleanupSession = vi.fn(async () => {
+    throw new Error('macOS session still owns host-macos-local');
+  });
+
+  const result = await runReplayTestAttempt({
+    filePath: '01-cleanup-failure.ad',
+    sessionName: 'default:test:cleanup-failure',
+    requestId: 'req-cleanup-failure',
+    runReplay: async () => ({
+      status: 'failed',
+      error: { code: 'COMMAND_FAILED', message: 'open "System Settings" failed' },
+      artifactPaths: [],
+      infrastructure: false,
+    }),
+    cleanupSession,
+    ...trackCancellation(),
+  });
+
+  expect(result.status).toBe('failed');
+  if (result.status === 'failed') {
+    expect(result.error.message).toBe('open "System Settings" failed');
+    expect(result.infrastructure).toBe(true);
+  }
+  expect(cleanupSession).toHaveBeenCalledWith('default:test:cleanup-failure');
+});
+
 // #1478 P3 characterization: attempt finalization happens before cleanup, always, and the
 // timing trace is the durable evidence of that order. P3 moves this `finally` orchestration
 // into replay-test, so the order and the recorded event names are pinned here as shipped.
diff --git a/packages/replay-test/src/internal/session-test-runtime.ts b/packages/replay-test/src/internal/session-test-runtime.ts
index ced7275d5..ecdf22b2f 100644
--- a/packages/replay-test/src/internal/session-test-runtime.ts
+++ b/packages/replay-test/src/internal/session-test-runtime.ts
@@ -190,6 +190,7 @@ export async function runReplayTestAttempt(
           error: appErr.message,
         },
       });
+      outcome = markReplayTestCleanupFailure(outcome, appErr, artifactPaths);
     }
   }
   return (
@@ -200,6 +201,27 @@ export async function runReplayTestAttempt(
   );
 }
 
+/**
+ * Cleanup is the ownership handoff between attempts. A failed cleanup leaves the prior attempt's
+ * device/session state unknown, so the scheduler must stop instead of retrying into a live claim.
+ * Keep an action failure as the user-facing cause when one already exists; the infrastructure tag
+ * is the scheduler-only fact that prevents a contended follow-up attempt.
+ */
+function markReplayTestCleanupFailure(
+  outcome: ReplayTestAttemptOutcome | undefined,
+  cleanupError: ReturnType<typeof normalizeError>,
+  artifactPaths: Set<string>,
+): ReplayTestAttemptOutcome {
+  if (outcome?.status === 'failed') {
+    return { ...outcome, infrastructure: true };
+  }
+  return replayTestAttemptFailure({
+    error: cleanupError,
+    artifactPaths: [...artifactPaths],
+    infrastructure: true,
+  });
+}
+
 async function waitForReplayAfterTimeout(
   replayPromise: Promise<ReplayTestAttemptOutcome>,
 ): Promise<boolean> {
diff --git a/src/daemon/handlers/__tests__/session-test-suite.test.ts b/src/daemon/handlers/__tests__/session-test-suite.test.ts
index a5a5866b6..418696a82 100644
--- a/src/daemon/handlers/__tests__/session-test-suite.test.ts
+++ b/src/daemon/handlers/__tests__/session-test-suite.test.ts
@@ -17,7 +17,7 @@ vi.mock('../snapshot-interactor-capture.ts', () => ({
 import fs from 'node:fs';
 import os from 'node:os';
 import path from 'node:path';
-import { handleSessionCommands } from './session-command-harness.ts';
+import { handleSessionCommands, mockInspectDeviceRuntimeFacts } from './session-command-harness.ts';
 import { SessionStore } from '../../session-store.ts';
 import type { DaemonRequest, DaemonResponse, DaemonResponseData } from '../../types.ts';
 import { withRequestProgressSink } from '../../../request/progress.ts';
@@ -29,7 +29,10 @@ import {
 } from '../../../request/cancel.ts';
 import { withTestDeviceInventoryProvider as withDeviceInventoryProvider } from '../../../__tests__/test-utils/device-inventory-gateways.ts';
 import type { DeviceInfo } from '@agent-device/kernel/device';
-import { makeAndroidSession } from '../../../__tests__/test-utils/session-factories.ts';
+import {
+  makeAndroidSession,
+  makeMacOsSession,
+} from '../../../__tests__/test-utils/session-factories.ts';
 
 function makeSessionStore(): SessionStore {
   const root = mkdtempForTestSync('agent-device-session-test-suite-');
@@ -324,6 +327,56 @@ test('test emits progress when attempts retry and pass', async () => {
   });
 });
 
+test('test stops before retrying when a rejected close leaves the prior macOS session owning its device', async () => {
+  const sessionStore = makeSessionStore();
+  const root = mkdtempForTestSync('agent-device-test-suite-macos-cleanup-failure-');
+  fs.writeFileSync(
+    path.join(root, '01-system-settings.ad'),
+    'context platform=macos\nopen "System Settings"\n',
+  );
+
+  let replayAttempts = 0;
+  const response = await handleSessionCommands({
+    req: {
+      token: 't',
+      session: 'default',
+      command: 'test',
+      positionals: [root],
+      meta: { cwd: root, requestId: 'suite-macos-cleanup-failure' },
+      flags: { retries: 2 },
+    },
+    sessionName: 'default',
+    logPath: path.join(os.tmpdir(), 'daemon.log'),
+    sessionStore,
+    inspectFacts: async (device) => {
+      const facts = await mockInspectDeviceRuntimeFacts(device);
+      return {
+        ...facts,
+        operations: {
+          ...facts.operations,
+          closeApplication: { available: false, reason: 'owner-capability-missing' },
+        },
+      };
+    },
+    invoke: async (req) => {
+      replayAttempts += 1;
+      sessionStore.set(req.session, makeMacOsSession(req.session));
+      return {
+        ok: false,
+        error: { code: 'COMMAND_FAILED', message: 'open "System Settings" failed' },
+      };
+    },
+  });
+
+  const data = expectOkData(response);
+  expect(replayAttempts).toBe(1);
+  expect(data.failed).toBe(1);
+  expect((data.tests as Array<Record<string, unknown>>)[0]).toMatchObject({
+    status: 'failed',
+    attempts: 1,
+  });
+});
+
 test('test stops retrying after maxAttempts when every attempt fails', async () => {
   const sessionStore = makeSessionStore();
   const root = mkdtempForTestSync('agent-device-test-suite-retry-exhaust-');
diff --git a/src/daemon/handlers/session-test-suite-command.ts b/src/daemon/handlers/session-test-suite-command.ts
index e11921823..f6f82c65a 100644
--- a/src/daemon/handlers/session-test-suite-command.ts
+++ b/src/daemon/handlers/session-test-suite-command.ts
@@ -304,7 +304,7 @@ export async function runReplayTestSuiteCommand(
     resolveShardTargets: buildReplayTestShardTargetResolver(req.flags),
     cleanupSession: async (testSessionName) => {
       if (!sessionStore.get(testSessionName)) return;
-      await handleCloseCommand({
+      const closeResponse = await handleCloseCommand({
         req: {
           token: req.token,
           session: testSessionName,
@@ -320,6 +320,12 @@ export async function runReplayTestSuiteCommand(
         inspectFacts: params.inspectFacts,
         bindDevice: params.bindDevice,
       });
+      if (!closeResponse.ok) {
+        throw new AppError(closeResponse.error.code, closeResponse.error.message, {
+          ...(closeResponse.error.details ?? {}),
+          ...(closeResponse.error.hint ? { hint: closeResponse.error.hint } : {}),
+        });
+      }
     },
   });
   return outcome.status === 'completed'