@@ -12,7 +12,6 @@ import type { DeviceInfo } from '@agent-device/kernel/device';
 import type { SessionState } from '../../session-state.ts';
 import type { DaemonRequest } from '../../daemon-request.ts';
 import { handleSessionCommands, mockInspectDeviceRuntimeFacts } from './session-command-harness.ts';
-import { handleSessionStateCommands } from '../session-state.ts';
 import { mkdtempForTestSync } from '../../../__tests__/test-utils/tmp-dir.ts';
 import { AppError } from '@agent-device/kernel/errors';
 import type {
@@ -453,25 +452,3 @@ test('appstate on iOS keeps the session answer, with no state, when the runner c
     expect(response.data).not.toHaveProperty('state');
   }
 });
-
-test('appstate returns missing-session error for explicit session flag', async () => {
-  const response = await handleSessionStateCommands({
-    platformServices: daemonPlatformServicesFixture(),
-    req: {
-      token: 't',
-      session: 'named',
-      command: 'appstate',
-      positionals: [],
-      flags: { platform: 'ios', session: 'named' },
-    },
-    sessionName: 'named',
-    sessionStore: makeSessionStore(),
-  });
-
-  expect(response).toBeTruthy();
-  expect(response?.ok).toBe(false);
-  if (response && !response.ok) {
-    expect(response.error.code).toBe('SESSION_NOT_FOUND');
-    expect(response.error.message).toMatch(/Run open with --session named first/i);
-  }
-});
@@ -0,0 +1,59 @@
+import { daemonPlatformServicesFixture } from '../../__tests__/platform-services-fixture.ts';
+import { test, expect } from 'vitest';
+import { makeSessionStore } from './session-test-harness.ts';
+import { handleAppStateCommand } from '../session-appstate.ts';
+import type { DaemonRequest } from '../../daemon-request.ts';
+
+function appStateRequest(session: string, flags: DaemonRequest['flags']): DaemonRequest {
+  return { token: 't', session, command: 'appstate', positionals: [], flags };
+}
+
+test('appstate returns missing-session error for explicit session flag', async () => {
+  const response = await handleAppStateCommand({
+    platformServices: daemonPlatformServicesFixture(),
+    req: appStateRequest('named', { platform: 'ios', session: 'named' }),
+    sessionName: 'named',
+    sessionStore: makeSessionStore(),
+  });
+
+  expect(response).toBeTruthy();
+  expect(response.ok).toBe(false);
+  if (!response.ok) {
+    expect(response.error.code).toBe('SESSION_NOT_FOUND');
+    expect(response.error.message).toMatch(/Run open with --session named first/i);
+  }
+});
+
+test('appstate refuses --platform ios without a session at the message level', async () => {
+  const response = await handleAppStateCommand({
+    platformServices: daemonPlatformServicesFixture(),
+    req: appStateRequest('default', { platform: 'ios', device: 'iPhone 17' }),
+    sessionName: 'default',
+    sessionStore: makeSessionStore(),
+  });
+
+  expect(response.ok).toBe(false);
+  if (!response.ok) {
+    expect(response.error.code).toBe('SESSION_NOT_FOUND');
+    expect(response.error.message).toBe(
+      'iOS appstate requires an active session on the target device. Run open first (for example: open --session sim --platform ios --device "<name>" <app>).',
+    );
+  }
+});
+
+test('appstate refuses --platform macos without a session at the message level', async () => {
+  const response = await handleAppStateCommand({
+    platformServices: daemonPlatformServicesFixture(),
+    req: appStateRequest('default', { platform: 'macos', device: 'Mac' }),
+    sessionName: 'default',
+    sessionStore: makeSessionStore(),
+  });
+
+  expect(response.ok).toBe(false);
+  if (!response.ok) {
+    expect(response.error.code).toBe('SESSION_NOT_FOUND');
+    expect(response.error.message).toBe(
+      'macOS appstate requires an active session on the target device. Run open first (for example: open --session macos --platform macos "System Settings").',
+    );
+  }
+});
@@ -18,7 +18,7 @@ import type { DaemonResponse } from '../daemon-request.ts';
  * The session facts this answer is built from, as a structural view: the handler reads exactly
  * the fields it uses and passes no more of the session shape than this.
  */
-type AppStateSessionRecord = Readonly<{
+export type AppStateSessionRecord = Readonly<{
   device: DeviceInfo;
   surface?: SessionSurface;
   appBundleId?: string;
 
@@ -11,6 +11,7 @@ import type { DaemonResponse } from '../daemon-request.ts';
 import {
   appleSessionAppStateResponse,
   appleSessionRequiredRefusal,
+  type AppStateSessionRecord,
 } from './session-appstate-apple-session.ts';
 import { queryDeviceRuntimeAppState } from './session-appstate-device-runtime.ts';
 
@@ -32,12 +33,19 @@ function appStateSessionNotFoundResponse(
 
 /**
  * Has this appstate request an answerable target, and which authority answers it: the Apple
- * session it points at, or the device runtime the selector resolves to. Every way the request can
- * be refused without a device answers here.
+ * session it points at, or the device runtime the selector resolves to. The apple-session branch
+ * carries the session itself, so answering it can never re-read the store for a session that has
+ * gone missing between admission and response. Every way the request can be refused without a
+ * device answers here.
  */
-function admitAppStateTarget(
-  params: RuntimeCommandHandlerParams,
-): { refusal: DaemonResponse } | { answeredBy: 'apple-session' | 'device-runtime' } {
+type AppStateSessionStoreEntry = ReturnType<RuntimeCommandHandlerParams['sessionStore']['get']>;
+
+type AppStateTargetDecision =
+  | { refusal: DaemonResponse }
+  | { answeredBy: 'apple-session'; session: AppStateSessionRecord }
+  | { answeredBy: 'device-runtime'; session: AppStateSessionStoreEntry };
+
+function admitAppStateTarget(params: RuntimeCommandHandlerParams): AppStateTargetDecision {
   const { req, sessionName, sessionStore } = params;
   const session = sessionStore.get(sessionName);
   const flags = req.flags ?? {};
@@ -59,7 +67,10 @@ function admitAppStateTarget(
   if (normalizedPlatform === 'macos' && !useSessionStateForApple) {
     return { refusal: appleSessionRequiredRefusal('macos') };
   }
-  return { answeredBy: useSessionStateForApple && session ? 'apple-session' : 'device-runtime' };
+  if (useSessionStateForApple && session) {
+    return { answeredBy: 'apple-session' as const, session };
+  }
+  return { answeredBy: 'device-runtime' as const, session };
 }
 
 /**
@@ -72,12 +83,11 @@ export async function handleAppStateCommand(
   const target = admitAppStateTarget(params);
   if ('refusal' in target) return target.refusal;
 
-  const session = params.sessionStore.get(params.sessionName);
-  if (target.answeredBy === 'apple-session' && session) {
-    return await appleSessionAppStateResponse(params, session);
+  if (target.answeredBy === 'apple-session') {
+    return await appleSessionAppStateResponse(params, target.session);
   }
   const device = await resolveCommandDevice({
-    session,
+    session: target.session,
     flags: params.req.flags ?? {},
     platformServices: params.platformServices,
   });