diff --git a/backend/app/auth/__init__.py b/backend/app/auth/__init__.py
index c9a3d5a5..45e5c0ec 100644
--- a/backend/app/auth/__init__.py
+++ b/backend/app/auth/__init__.py
@@ -19,6 +19,12 @@ from app.auth.brain_auth import (
     set_brain_auth_provider,
     with_brain_auth_provider,
 )
+from app.auth.local_control import (
+    LOCAL_CONTROL_CAPABILITY_ENV,
+    LOCAL_CONTROL_CAPABILITY_HEADER,
+    LocalControlPrincipal,
+    require_local_control_principal,
+)
 from app.auth.interface import IAuthProvider, NoneAuth
 
 __all__ = [
@@ -29,4 +35,8 @@ __all__ = [
     "get_brain_auth_provider",
     "set_brain_auth_provider",
     "with_brain_auth_provider",
+    "LOCAL_CONTROL_CAPABILITY_ENV",
+    "LOCAL_CONTROL_CAPABILITY_HEADER",
+    "LocalControlPrincipal",
+    "require_local_control_principal",
 ]
diff --git a/backend/app/auth/local_control.py b/backend/app/auth/local_control.py
new file mode 100644
index 00000000..e7fc279a
--- /dev/null
+++ b/backend/app/auth/local_control.py
@@ -0,0 +1,104 @@
+"""Authentication boundary for Desktop-local Run and Command control APIs."""
+
+from __future__ import annotations
+
+import hmac
+import ipaddress
+import os
+from dataclasses import dataclass
+
+from fastapi import HTTPException, Request
+
+from app.auth.brain_auth import (
+    get_brain_auth_context,
+    get_brain_auth_provider,
+)
+from app.auth.interface import NoneAuth
+
+LOCAL_CONTROL_CAPABILITY_ENV = "EIGENT_LOCAL_CONTROL_CAPABILITY"
+LOCAL_CONTROL_CAPABILITY_HEADER = "X-Eigent-Local-Capability"
+
+
+@dataclass(frozen=True)
+class LocalControlPrincipal:
+    kind: str
+    user_id: str
+
+
+def _is_loopback(host: str | None) -> bool:
+    if not host:
+        return False
+    if host.lower() == "localhost":
+        return True
+    try:
+        return ipaddress.ip_address(host).is_loopback
+    except ValueError:
+        return False
+
+
+async def require_local_control_principal(
+    request: Request,
+) -> LocalControlPrincipal:
+    """Authorize the renderer capability or an authenticated remote Brain user.
+
+    Electron injects a random capability into the child Brain process and gives
+    it to the trusted renderer through IPC. It is deliberately separate from
+    Cloud device credentials, user bearer tokens, and Remote Control link tokens.
+    """
+
+    expected = os.environ.get(LOCAL_CONTROL_CAPABILITY_ENV, "")
+    if expected:
+        if not _is_loopback(getattr(request.client, "host", None)):
+            raise HTTPException(
+                status_code=403,
+                detail={
+                    "code": "local_control_loopback_required",
+                    "message": "Desktop control APIs only accept loopback clients.",
+                },
+            )
+        presented = request.headers.get(LOCAL_CONTROL_CAPABILITY_HEADER, "")
+        if not presented or not hmac.compare_digest(presented, expected):
+            raise HTTPException(
+                status_code=401,
+                detail={
+                    "code": "local_control_capability_required",
+                    "message": "A valid Desktop control capability is required.",
+                },
+            )
+        principal = LocalControlPrincipal(kind="desktop_renderer", user_id="local")
+        request.state.local_control_principal = principal
+        return principal
+
+    if os.environ.get("EIGENT_RUNTIME", "").lower() == "electron":
+        raise HTTPException(
+            status_code=503,
+            detail={
+                "code": "local_control_capability_unconfigured",
+                "message": "Desktop control capability is not configured.",
+            },
+        )
+
+    # Non-Electron deployments must configure a real Brain auth provider.
+    # Header presence alone is not authentication while NoneAuth is active.
+    if isinstance(get_brain_auth_provider(), NoneAuth):
+        raise HTTPException(
+            status_code=503,
+            detail={
+                "code": "local_control_auth_unconfigured",
+                "message": "Control API authentication is not configured.",
+            },
+        )
+    brain_auth = await get_brain_auth_context(request)
+    if not brain_auth.authorization_present:
+        raise HTTPException(
+            status_code=401,
+            detail={
+                "code": "brain_auth_required_for_control",
+                "message": "Brain authentication is required for control APIs.",
+            },
+        )
+    principal = LocalControlPrincipal(
+        kind="brain_user", user_id=brain_auth.user_id
+    )
+    request.state.local_control_principal = principal
+    return principal
diff --git a/backend/app/controller/remote_command_controller.py b/backend/app/controller/remote_command_controller.py
index 5e03f995..55843a84 100644
--- a/backend/app/controller/remote_command_controller.py
+++ b/backend/app/controller/remote_command_controller.py
@@ -8,16 +8,20 @@ from dataclasses import asdict
 from datetime import UTC, datetime, timedelta
 from typing import Any, Literal
 
-from fastapi import APIRouter, HTTPException
+from fastapi import APIRouter, Depends, HTTPException
 from pydantic import BaseModel, Field
 
+from app.auth import require_local_control_principal
 from app.run_journal import get_default_run_journal
 from app.run_sync.runtime import (
     notify_default_cloud_sync_worker,
     persist_and_confirm_remote_command,
 )
 
-router = APIRouter(prefix="/remote-control/commands")
+router = APIRouter(
+    prefix="/remote-control/commands",
+    dependencies=[Depends(require_local_control_principal)],
+)
 
 _HIGH_RISK_COMMAND_TYPES = {
     "stop",
diff --git a/backend/app/controller/run_controller.py b/backend/app/controller/run_controller.py
index c662705b..741f87d9 100644
--- a/backend/app/controller/run_controller.py
+++ b/backend/app/controller/run_controller.py
@@ -29,10 +29,11 @@ from contextlib import suppress
 from dataclasses import asdict
 from typing import Any
 
-from fastapi import APIRouter, HTTPException, Query
+from fastapi import APIRouter, Depends, HTTPException, Query
 from fastapi.responses import StreamingResponse
 from pydantic import BaseModel, Field
 
+from app.auth import require_local_control_principal
 from app.run_journal import (
     CommittedRunEvent,
     IdempotencyConflictError,
@@ -54,7 +55,7 @@ from app.run_runtime import (
     get_default_run_coordinator,
 )
 
-router = APIRouter()
+router = APIRouter(dependencies=[Depends(require_local_control_principal)])
 
 _EVENT_PAGE_SIZE = 500
 _DEFAULT_HEARTBEAT_SECONDS = 15.0
diff --git a/backend/tests/app/auth/test_local_control.py b/backend/tests/app/auth/test_local_control.py
new file mode 100644
index 00000000..80931b64
--- /dev/null
+++ b/backend/tests/app/auth/test_local_control.py
@@ -0,0 +1,193 @@
+from __future__ import annotations
+
+from unittest.mock import MagicMock, patch
+
+from fastapi import FastAPI, Request
+from fastapi.testclient import TestClient
+
+from app.auth.brain_auth import with_brain_auth_provider
+from app.auth.interface import IAuthProvider
+from app.auth.local_control import (
+    LOCAL_CONTROL_CAPABILITY_HEADER,
+    require_local_control_principal,
+)
+from app.controller import remote_command_controller, run_controller
+
+
+class _VerifiedAuth(IAuthProvider):
+    async def authenticate(self, scope):
+        _ = scope
+        return {"user_id": "user-1", "tenant_id": "tenant-1"}
+
+
+class _UnexpectedCloudAuth(IAuthProvider):
+    async def authenticate(self, scope):
+        _ = scope
+        raise AssertionError("Desktop capability must not invoke Cloud auth")
+
+
+def _app() -> FastAPI:
+    app = FastAPI()
+
+    @app.get("/control")
+    async def control(request: Request):
+        return await require_local_control_principal(request)
+
+    return app
+
+
+def test_electron_control_requires_matching_loopback_capability(monkeypatch):
+    monkeypatch.setenv("EIGENT_RUNTIME", "electron")
+    monkeypatch.setenv("EIGENT_LOCAL_CONTROL_CAPABILITY", "secret-1")
+    client = TestClient(_app(), client=("127.0.0.1", 50000))
+
+    assert client.get("/control").status_code == 401
+    assert (
+        client.get(
+            "/control", headers={LOCAL_CONTROL_CAPABILITY_HEADER: "wrong"}
+        ).status_code
+        == 401
+    )
+    response = client.get(
+        "/control", headers={LOCAL_CONTROL_CAPABILITY_HEADER: "secret-1"}
+    )
+    assert response.status_code == 200
+    assert response.json()["kind"] == "desktop_renderer"
+
+
+def test_device_and_link_identity_do_not_replace_renderer_capability(monkeypatch):
+    monkeypatch.setenv("EIGENT_RUNTIME", "electron")
+    monkeypatch.setenv("EIGENT_LOCAL_CONTROL_CAPABILITY", "secret-1")
+    client = TestClient(_app(), client=("127.0.0.1", 50000))
+
+    response = client.get(
+        "/control",
+        headers={
+            "Authorization": "Bearer cloud-user-token",
+            "X-Desktop-Instance-ID": "device-1",
+            "X-Remote-Control-Token": "link-1",
+        },
+    )
+
+    assert response.status_code == 401
+
+
+def test_desktop_capability_is_independent_from_cloud_auth(monkeypatch):
+    monkeypatch.setenv("EIGENT_RUNTIME", "electron")
+    monkeypatch.setenv("EIGENT_LOCAL_CONTROL_CAPABILITY", "secret-1")
+    client = TestClient(_app(), client=("127.0.0.1", 50000))
+
+    with with_brain_auth_provider(_UnexpectedCloudAuth()):
+        response = client.get(
+            "/control",
+            headers={LOCAL_CONTROL_CAPABILITY_HEADER: "secret-1"},
+        )
+
+    assert response.status_code == 200
+
+
+def test_electron_control_fails_closed_when_capability_is_missing(monkeypatch):
+    monkeypatch.setenv("EIGENT_RUNTIME", "electron")
+    monkeypatch.delenv("EIGENT_LOCAL_CONTROL_CAPABILITY", raising=False)
+
+    response = TestClient(_app()).get(
+        "/control", headers={"Authorization": "Bearer cloud-user-token"}
+    )
+
+    assert response.status_code == 503
+
+
+def test_non_loopback_cannot_use_desktop_capability(monkeypatch):
+    monkeypatch.setenv("EIGENT_LOCAL_CONTROL_CAPABILITY", "secret-1")
+    client = TestClient(_app(), client=("203.0.113.8", 50000))
+
+    response = client.get(
+        "/control", headers={LOCAL_CONTROL_CAPABILITY_HEADER: "secret-1"}
+    )
+
+    assert response.status_code == 403
+
+
+def test_rotated_desktop_capability_rejects_the_previous_process_token(
+    monkeypatch,
+):
+    monkeypatch.setenv("EIGENT_RUNTIME", "electron")
+    monkeypatch.setenv("EIGENT_LOCAL_CONTROL_CAPABILITY", "startup-1")
+    client = TestClient(_app(), client=("127.0.0.1", 50000))
+    assert (
+        client.get(
+            "/control",
+            headers={LOCAL_CONTROL_CAPABILITY_HEADER: "startup-1"},
+        ).status_code
+        == 200
+    )
+
+    monkeypatch.setenv("EIGENT_LOCAL_CONTROL_CAPABILITY", "startup-2")
+
+    assert (
+        client.get(
+            "/control",
+            headers={LOCAL_CONTROL_CAPABILITY_HEADER: "startup-1"},
+        ).status_code
+        == 401
+    )
+    assert (
+        client.get(
+            "/control",
+            headers={LOCAL_CONTROL_CAPABILITY_HEADER: "startup-2"},
+        ).status_code
+        == 200
+    )
+
+
+def test_non_electron_control_requires_brain_authorization(monkeypatch):
+    monkeypatch.delenv("EIGENT_RUNTIME", raising=False)
+    monkeypatch.delenv("EIGENT_LOCAL_CONTROL_CAPABILITY", raising=False)
+    client = TestClient(_app())
+
+    assert client.get("/control").status_code == 503
+    assert (
+        client.get(
+            "/control", headers={"Authorization": "Bearer unverified-token"}
+        ).status_code
+        == 503
+    )
+    with with_brain_auth_provider(_VerifiedAuth()):
+        assert client.get("/control").status_code == 401
+        response = client.get(
+            "/control", headers={"Authorization": "Bearer verified-token"}
+        )
+        assert response.status_code == 200
+        assert response.json()["kind"] == "brain_user"
+
+
+def test_run_and_command_routers_enforce_the_control_principal(monkeypatch):
+    monkeypatch.setenv("EIGENT_RUNTIME", "electron")
+    monkeypatch.setenv("EIGENT_LOCAL_CONTROL_CAPABILITY", "secret-1")
+    app = FastAPI()
+    app.include_router(run_controller.router)
+    app.include_router(remote_command_controller.router)
+    client = TestClient(app, client=("127.0.0.1", 50000))
+    journal = MagicMock()
+    journal.get_run.return_value = None
+    journal.list_reconcilable_commands.return_value = []
+
+    assert client.get("/runs/missing").status_code == 401
+    assert client.get("/remote-control/commands/inbox/pending").status_code == 401
+    with (
+        patch(
+            "app.controller.run_controller.get_default_run_journal",
+            return_value=journal,
+        ),
+        patch(
+            "app.controller.remote_command_controller.get_default_run_journal",
+            return_value=journal,
+        ),
+    ):
+        headers = {LOCAL_CONTROL_CAPABILITY_HEADER: "secret-1"}
+        assert client.get("/runs/missing", headers=headers).status_code == 404
+        response = client.get(
+            "/remote-control/commands/inbox/pending", headers=headers
+        )
+        assert response.status_code == 200
+        assert response.json() == {"items": []}
diff --git a/electron/main/index.ts b/electron/main/index.ts
index 397e30f8..90078c6c 100644
--- a/electron/main/index.ts
+++ b/electron/main/index.ts
@@ -93,6 +93,7 @@ let fileReader: FileReader | null = null;
 let python_process: ChildProcessWithoutNullStreams | null = null;
 let backendPort: number = 5001;
 let backendStartPromise: Promise<BackendStartResult> | null = null;
+const localControlCapability = crypto.randomBytes(32).toString('base64url');
 let browser_port = 9222;
 let use_external_cdp = false;
 let proxyUrl: string | null = null;
@@ -1059,6 +1060,14 @@ function registerIpcHandlers() {
 
   ipcMain.handle('get-app-version', () => app.getVersion());
   ipcMain.handle('get-backend-port', () => backendPort);
+  ipcMain.handle('get-local-control-capability', (event) => {
+    if (!win || event.sender.id !== win.webContents.id) {
+      throw new Error(
+        'Local control capability is restricted to the main renderer'
+      );
+    }
+    return localControlCapability;
+  });
 
   // ==================== restart app handler ====================
   ipcMain.handle('restart-app', async () => {
@@ -3169,6 +3178,7 @@ const checkAndStartBackend = async (
           {
             ...codexResolverEnv,
             EIGENT_EXAMPLE_SKILLS_DIR: exampleSkillsDir,
+            EIGENT_LOCAL_CONTROL_CAPABILITY: localControlCapability,
           }
         );
 
diff --git a/electron/preload/index.ts b/electron/preload/index.ts
index caa4d5cf..63cf9a67 100644
--- a/electron/preload/index.ts
+++ b/electron/preload/index.ts
@@ -118,6 +118,8 @@ contextBridge.exposeInMainWorld('electronAPI', {
   checkInstallBrowser: () => ipcRenderer.invoke('check-install-browser'),
   getInstallationStatus: () => ipcRenderer.invoke('get-installation-status'),
   getBackendPort: () => ipcRenderer.invoke('get-backend-port'),
+  getLocalControlCapability: () =>
+    ipcRenderer.invoke('get-local-control-capability'),
   restartBackend: () => ipcRenderer.invoke('restart-backend'),
   onInstallDependenciesStart: (callback: () => void) => {
     ipcRenderer.on('install-dependencies-start', callback);
diff --git a/src/api/http.ts b/src/api/http.ts
index cdd5dd1a..cb6932e4 100644
--- a/src/api/http.ts
+++ b/src/api/http.ts
@@ -30,6 +30,32 @@ import {
 const defaultHeaders = {
   'Content-Type': 'application/json',
 };
+const LOCAL_CONTROL_CAPABILITY_HEADER = 'X-Eigent-Local-Capability';
+let localControlCapabilityPromise: Promise<string> | null = null;
+
+export async function getLocalControlCapability(): Promise<string> {
+  const api = createHost().electronAPI;
+  if (!api?.getLocalControlCapability) {
+    return '';
+  }
+  if (!localControlCapabilityPromise) {
+    localControlCapabilityPromise = Promise.resolve(
+      api.getLocalControlCapability()
+    ).then(
+      (token) => {
+        if (!token) {
+          localControlCapabilityPromise = null;
+        }
+        return token || '';
+      },
+      () => {
+        localControlCapabilityPromise = null;
+        return '';
+      }
+    );
+  }
+  return localControlCapabilityPromise;
+}
 
 export function getDefaultBrainEndpoint(): string {
   const envEndpoint = import.meta.env.VITE_BRAIN_ENDPOINT;
@@ -60,11 +86,11 @@ function shouldAttachAuthHeader(url: string): boolean {
   return !url.includes('http://') && !url.includes('https://');
 }
 
-function buildBrainHeaders(
+async function buildBrainHeaders(
   url: string,
   customHeaders: Record<string, string> = {},
   includeContentType = true
-): Record<string, string> {
+): Promise<Record<string, string>> {
   const { token, user_id } = getAuthStore();
   const conn = getConnectionConfig();
   const headers: Record<string, string> = {
@@ -80,6 +106,10 @@ function buildBrainHeaders(
   }
   if (shouldAttachAuthHeader(url)) {
     headers['X-Desktop-Instance-ID'] = getDesktopInstanceId();
+    const localControlCapability = await getLocalControlCapability();
+    if (localControlCapability) {
+      headers[LOCAL_CONTROL_CAPABILITY_HEADER] = localControlCapability;
+    }
   }
   if (user_id != null) {
     headers['X-User-ID'] = String(user_id);
@@ -127,7 +157,7 @@ async function fetchRequest(
 ): Promise<any> {
   const baseURL = await getBaseURL();
   const fullUrl = `${baseURL}${url}`;
-  const headers = buildBrainHeaders(url, customHeaders);
+  const headers = await buildBrainHeaders(url, customHeaders);
 
   const options: RequestInit = {
     method,
@@ -291,7 +321,7 @@ export async function fetchPostForm(
 ): Promise<any> {
   const baseURL = await getBaseURL();
   const fullUrl = `${baseURL}${url}`;
-  const headers = buildBrainHeaders(url, customHeaders, false);
+  const headers = await buildBrainHeaders(url, customHeaders, false);
   return handleResponse(
     fetch(fullUrl, { method: 'POST', headers, body: formData })
   );
@@ -329,7 +359,7 @@ export async function sseTransport(
       ? options.url
       : `${baseURL}${options.url}`;
 
-  const headers = buildBrainHeaders(options.url, options.extraHeaders);
+  const headers = await buildBrainHeaders(options.url, options.extraHeaders);
   const body =
     typeof options.body === 'string'
       ? options.body
diff --git a/src/hooks/useRemoteControlBridge.ts b/src/hooks/useRemoteControlBridge.ts
index 1cb19e29..393aa0d6 100644
--- a/src/hooks/useRemoteControlBridge.ts
+++ b/src/hooks/useRemoteControlBridge.ts
@@ -12,7 +12,13 @@
 // limitations under the License.
 // ========= Copyright 2025-2026 @ Eigent.ai All Rights Reserved. =========
 
-import { getBaseURL, proxyFetchGet, proxyFetchPost } from '@/api/http';
+import {
+  fetchGet,
+  fetchPost,
+  getBaseURL,
+  getLocalControlCapability,
+  proxyFetchGet,
+} from '@/api/http';
 import { isDesktop } from '@/client/platform';
 import {
   getRemoteControlDesktopInstanceId,
@@ -290,12 +296,16 @@ async function requestBrain(
   );
   try {
     const baseURL = await getBaseURL();
+    const localControlCapability = await getLocalControlCapability();
     const response = await fetch(`${baseURL}${path}`, {
       method,
       signal: controller.signal,
       headers: {
         ...brainHeaders(command),
         Authorization: `Bearer ${token}`,
+        ...(localControlCapability
+          ? { 'X-Eigent-Local-Capability': localControlCapability }
+          : {}),
       },
       body: body ? JSON.stringify(body) : undefined,
     });
@@ -994,7 +1004,7 @@ export function useRemoteControlBridge(token: string | null | undefined) {
       body: CommandResultBody
     ) => {
       queuePendingCommandResult({ command, body });
-      await proxyFetchPost(
+      await fetchPost(
         `/remote-control/commands/${encodeURIComponent(command.id)}/result`,
         body,
         brainHeaders(command)
@@ -1018,7 +1028,7 @@ export function useRemoteControlBridge(token: string | null | undefined) {
     const persistCommandAndExecute = async (
       command: RemoteCommand
     ): Promise<BridgeAck> => {
-      const persisted = await proxyFetchPost(
+      const persisted = await fetchPost(
         '/remote-control/commands/inbox',
         command,
         brainHeaders(command)
@@ -1083,7 +1093,7 @@ export function useRemoteControlBridge(token: string | null | undefined) {
         };
       }
       if (!persisted?.may_execute) {
-        await proxyFetchPost(
+        await fetchPost(
           `/remote-control/commands/${encodeURIComponent(command.id)}/admission`,
           {
             status: 'rejected',
@@ -1101,7 +1111,7 @@ export function useRemoteControlBridge(token: string | null | undefined) {
         };
       }
 
-      await proxyFetchPost(
+      await fetchPost(
         `/remote-control/commands/${encodeURIComponent(command.id)}/admission`,
         {
           status: 'accepted',
@@ -1191,7 +1201,7 @@ export function useRemoteControlBridge(token: string | null | undefined) {
 
     const replayDurableInbox = async () => {
       try {
-        const response = await proxyFetchGet(
+        const response = await fetchGet(
           '/remote-control/commands/inbox/pending',
           { limit: 100 }
         );
diff --git a/src/types/electron.d.ts b/src/types/electron.d.ts
index 93dd4dc2..55d25de8 100644
--- a/src/types/electron.d.ts
+++ b/src/types/electron.d.ts
@@ -150,6 +150,7 @@ interface ElectronAPI {
     error?: string;
   }>;
   getBackendPort: () => Promise<number | null>;
+  getLocalControlCapability: () => Promise<string>;
   restartBackend: () => Promise<{ success: boolean; error?: string }>;
   onInstallDependenciesStart: (callback: () => void) => void;
   onInstallDependenciesLog: (
diff --git a/test/unit/api/http.test.ts b/test/unit/api/http.test.ts
index 781e49d4..aa1f06f4 100644
--- a/test/unit/api/http.test.ts
+++ b/test/unit/api/http.test.ts
@@ -18,20 +18,34 @@ vi.mock('@/store/authStore', () => ({
   getAuthStore: () => ({ token: null }),
 }));
 
-const showCreditsToast = vi.fn();
-const showStorageToast = vi.fn();
-const showTrafficToast = vi.fn();
+const mocked = vi.hoisted(() => ({
+  getLocalControlCapability: vi.fn(() =>
+    Promise.resolve('renderer-capability')
+  ),
+  showCreditsToast: vi.fn(),
+  showStorageToast: vi.fn(),
+  showTrafficToast: vi.fn(),
+}));
+
+vi.mock('@/host/createHost', () => ({
+  createHost: () => ({
+    electronAPI: {
+      getLocalControlCapability: mocked.getLocalControlCapability,
+    },
+    ipcRenderer: null,
+  }),
+}));
 
 vi.mock('@/components/Toast/creditsToast', () => ({
-  showCreditsToast,
+  showCreditsToast: mocked.showCreditsToast,
 }));
 
 vi.mock('@/components/Toast/storageToast', () => ({
-  showStorageToast,
+  showStorageToast: mocked.showStorageToast,
 }));
 
 vi.mock('@/components/Toast/trafficToast', () => ({
-  showTrafficToast,
+  showTrafficToast: mocked.showTrafficToast,
 }));
 
 import { fetchPost, getBaseURL } from '@/api/http';
@@ -47,9 +61,9 @@ describe('api/http handleResponse', () => {
       brainEndpoint: 'http://brain.local',
       channel: 'web',
     });
-    showCreditsToast.mockClear();
-    showStorageToast.mockClear();
-    showTrafficToast.mockClear();
+    mocked.showCreditsToast.mockClear();
+    mocked.showStorageToast.mockClear();
+    mocked.showTrafficToast.mockClear();
     vi.restoreAllMocks();
   });
 
@@ -74,7 +88,28 @@ describe('api/http handleResponse', () => {
 
     const res = await fetchPost('/chat', { question: 'x' });
     expect(res.code).toBe(20);
-    expect(showCreditsToast).toHaveBeenCalledTimes(1);
+    expect(mocked.showCreditsToast).toHaveBeenCalledTimes(1);
+  });
+
+  it('attaches the ephemeral renderer capability to Brain requests', async () => {
+    const request = vi
+      .spyOn(globalThis, 'fetch')
+      .mockResolvedValue(new Response(null, { status: 204 }));
+
+    await fetchPost(
+      '/runs/run-1/cancel',
+      { request_id: 'cancel-1' },
+      { 'X-Eigent-Local-Capability': 'forged-capability' }
+    );
+
+    expect(request).toHaveBeenCalledWith(
+      'http://brain.local/runs/run-1/cancel',
+      expect.objectContaining({
+        headers: expect.objectContaining({
+          'X-Eigent-Local-Capability': 'renderer-capability',
+        }),
+      })
+    );
   });
 });
 
diff --git a/test/unit/hooks/useRemoteControlBridge.test.ts b/test/unit/hooks/useRemoteControlBridge.test.ts
index e1229b1a..ab9b5d1d 100644
--- a/test/unit/hooks/useRemoteControlBridge.test.ts
+++ b/test/unit/hooks/useRemoteControlBridge.test.ts
@@ -16,9 +16,13 @@ import { afterEach, beforeEach, describe, expect, it, vi } from 'vitest';
 
 vi.mock('@/api/http', () => ({
   fetchDelete: vi.fn(),
+  fetchGet: vi.fn(() => Promise.resolve({ items: [] })),
   fetchPost: vi.fn(),
   fetchPut: vi.fn(),
   getBaseURL: vi.fn(() => Promise.resolve('')),
+  getLocalControlCapability: vi.fn(() =>
+    Promise.resolve('renderer-capability')
+  ),
   proxyFetchGet: vi.fn(() => Promise.resolve({ items: [] })),
   proxyFetchPost: vi.fn(() => Promise.resolve({ id: 'history-id' })),
   proxyFetchPut: vi.fn(),
@@ -120,6 +124,13 @@ describe('useRemoteControlBridge internals', () => {
     expect(fetchSpy).toHaveBeenCalledTimes(2);
     expect(fetchSpy.mock.calls[0]?.[0]).toBe('/chat/project-target/status');
     expect(fetchSpy.mock.calls[1]?.[0]).toBe('/chat/project-target');
+    expect(fetchSpy.mock.calls[0]?.[1]).toEqual(
+      expect.objectContaining({
+        headers: expect.objectContaining({
+          'X-Eigent-Local-Capability': 'renderer-capability',
+        }),
+      })
+    );
   });
 
   it('starts local user_message tasks against the target Project without switching foreground Project', async () => {