diff --git a/extensions/google-gemini-cli-auth/oauth.test.ts b/extensions/google-gemini-cli-auth/oauth.test.ts
index 3d5df634ff6..46a12a0a5ee 100644
--- a/extensions/google-gemini-cli-auth/oauth.test.ts
+++ b/extensions/google-gemini-cli-auth/oauth.test.ts
@@ -3,6 +3,19 @@ import { describe, expect, it, vi, beforeEach, afterEach } from "vitest";
 
 vi.mock("openclaw/plugin-sdk", () => ({
   isWSL2Sync: () => false,
+  fetchWithSsrFGuard: async (params: {
+    url: string;
+    init?: RequestInit;
+    fetchImpl?: (input: RequestInfo | URL, init?: RequestInit) => Promise<Response>;
+  }) => {
+    const fetchImpl = params.fetchImpl ?? globalThis.fetch;
+    const response = await fetchImpl(params.url, params.init);
+    return {
+      response,
+      finalUrl: params.url,
+      release: async () => {},
+    };
+  },
 }));
 
 // Mock fs module before importing the module under test
@@ -208,3 +221,204 @@ describe("extractGeminiCliCredentials", () => {
     expect(mockReadFileSync.mock.calls.length).toBe(readCount);
   });
 });
+
+describe("loginGeminiCliOAuth", () => {
+  const TOKEN_URL = "https://oauth2.googleapis.com/token";
+  const USERINFO_URL = "https://www.googleapis.com/oauth2/v1/userinfo?alt=json";
+  const LOAD_PROD = "https://cloudcode-pa.googleapis.com/v1internal:loadCodeAssist";
+  const LOAD_DAILY = "https://daily-cloudcode-pa.sandbox.googleapis.com/v1internal:loadCodeAssist";
+  const LOAD_AUTOPUSH =
+    "https://autopush-cloudcode-pa.sandbox.googleapis.com/v1internal:loadCodeAssist";
+
+  const ENV_KEYS = [
+    "OPENCLAW_GEMINI_OAUTH_CLIENT_ID",
+    "OPENCLAW_GEMINI_OAUTH_CLIENT_SECRET",
+    "GEMINI_CLI_OAUTH_CLIENT_ID",
+    "GEMINI_CLI_OAUTH_CLIENT_SECRET",
+    "GOOGLE_CLOUD_PROJECT",
+    "GOOGLE_CLOUD_PROJECT_ID",
+  ] as const;
+
+  function getExpectedPlatform(): "WINDOWS" | "MACOS" | "LINUX" {
+    if (process.platform === "win32") {
+      return "WINDOWS";
+    }
+    if (process.platform === "linux") {
+      return "LINUX";
+    }
+    return "MACOS";
+  }
+
+  function getRequestUrl(input: string | URL | Request): string {
+    return typeof input === "string" ? input : input instanceof URL ? input.toString() : input.url;
+  }
+
+  function getHeaderValue(headers: HeadersInit | undefined, name: string): string | undefined {
+    if (!headers) {
+      return undefined;
+    }
+    if (headers instanceof Headers) {
+      return headers.get(name) ?? undefined;
+    }
+    if (Array.isArray(headers)) {
+      return headers.find(([key]) => key.toLowerCase() === name.toLowerCase())?.[1];
+    }
+    return (headers as Record<string, string>)[name];
+  }
+
+  function responseJson(body: unknown, status = 200): Response {
+    return new Response(JSON.stringify(body), {
+      status,
+      headers: { "Content-Type": "application/json" },
+    });
+  }
+
+  let envSnapshot: Partial<Record<(typeof ENV_KEYS)[number], string>>;
+  beforeEach(() => {
+    envSnapshot = Object.fromEntries(ENV_KEYS.map((key) => [key, process.env[key]]));
+    process.env.OPENCLAW_GEMINI_OAUTH_CLIENT_ID = "test-client-id.apps.googleusercontent.com";
+    process.env.OPENCLAW_GEMINI_OAUTH_CLIENT_SECRET = "GOCSPX-test-client-secret";
+    delete process.env.GEMINI_CLI_OAUTH_CLIENT_ID;
+    delete process.env.GEMINI_CLI_OAUTH_CLIENT_SECRET;
+    delete process.env.GOOGLE_CLOUD_PROJECT;
+    delete process.env.GOOGLE_CLOUD_PROJECT_ID;
+  });
+
+  afterEach(() => {
+    for (const key of ENV_KEYS) {
+      const value = envSnapshot[key];
+      if (value === undefined) {
+        delete process.env[key];
+      } else {
+        process.env[key] = value;
+      }
+    }
+    vi.unstubAllGlobals();
+  });
+
+  it("falls back across loadCodeAssist endpoints with aligned headers and metadata", async () => {
+    const requests: Array<{ url: string; init?: RequestInit }> = [];
+    const fetchMock = vi.fn(async (input: string | URL | Request, init?: RequestInit) => {
+      const url = getRequestUrl(input);
+      requests.push({ url, init });
+
+      if (url === TOKEN_URL) {
+        return responseJson({
+          access_token: "access-token",
+          refresh_token: "refresh-token",
+          expires_in: 3600,
+        });
+      }
+      if (url === USERINFO_URL) {
+        return responseJson({ email: "lobster@openclaw.ai" });
+      }
+      if (url === LOAD_PROD) {
+        return responseJson({ error: { message: "temporary failure" } }, 503);
+      }
+      if (url === LOAD_DAILY) {
+        return responseJson({
+          currentTier: { id: "standard-tier" },
+          cloudaicompanionProject: { id: "daily-project" },
+        });
+      }
+      throw new Error(`Unexpected request: ${url}`);
+    });
+    vi.stubGlobal("fetch", fetchMock);
+
+    let authUrl = "";
+    const { loginGeminiCliOAuth } = await import("./oauth.js");
+    const result = await loginGeminiCliOAuth({
+      isRemote: true,
+      openUrl: async () => {},
+      log: (msg) => {
+        const found = msg.match(/https:\/\/accounts\.google\.com\/o\/oauth2\/v2\/auth\?[^\s]+/);
+        if (found?.[0]) {
+          authUrl = found[0];
+        }
+      },
+      note: async () => {},
+      prompt: async () => {
+        const state = new URL(authUrl).searchParams.get("state");
+        return `${"http://localhost:8085/oauth2callback"}?code=oauth-code&state=${state}`;
+      },
+      progress: { update: () => {}, stop: () => {} },
+    });
+
+    expect(result.projectId).toBe("daily-project");
+    const loadRequests = requests.filter((request) =>
+      request.url.includes("v1internal:loadCodeAssist"),
+    );
+    expect(loadRequests.map((request) => request.url)).toEqual([LOAD_PROD, LOAD_DAILY]);
+
+    const firstHeaders = loadRequests[0]?.init?.headers;
+    expect(getHeaderValue(firstHeaders, "X-Goog-Api-Client")).toBe(
+      `gl-node/${process.versions.node}`,
+    );
+
+    const clientMetadata = getHeaderValue(firstHeaders, "Client-Metadata");
+    expect(clientMetadata).toBeDefined();
+    expect(JSON.parse(clientMetadata as string)).toEqual({
+      ideType: "ANTIGRAVITY",
+      platform: getExpectedPlatform(),
+      pluginType: "GEMINI",
+    });
+
+    const body = JSON.parse(String(loadRequests[0]?.init?.body));
+    expect(body).toEqual({
+      metadata: {
+        ideType: "ANTIGRAVITY",
+        platform: getExpectedPlatform(),
+        pluginType: "GEMINI",
+      },
+    });
+  });
+
+  it("falls back to GOOGLE_CLOUD_PROJECT when all loadCodeAssist endpoints fail", async () => {
+    process.env.GOOGLE_CLOUD_PROJECT = "env-project";
+
+    const requests: string[] = [];
+    const fetchMock = vi.fn(async (input: string | URL | Request) => {
+      const url = getRequestUrl(input);
+      requests.push(url);
+
+      if (url === TOKEN_URL) {
+        return responseJson({
+          access_token: "access-token",
+          refresh_token: "refresh-token",
+          expires_in: 3600,
+        });
+      }
+      if (url === USERINFO_URL) {
+        return responseJson({ email: "lobster@openclaw.ai" });
+      }
+      if ([LOAD_PROD, LOAD_DAILY, LOAD_AUTOPUSH].includes(url)) {
+        return responseJson({ error: { message: "unavailable" } }, 503);
+      }
+      throw new Error(`Unexpected request: ${url}`);
+    });
+    vi.stubGlobal("fetch", fetchMock);
+
+    let authUrl = "";
+    const { loginGeminiCliOAuth } = await import("./oauth.js");
+    const result = await loginGeminiCliOAuth({
+      isRemote: true,
+      openUrl: async () => {},
+      log: (msg) => {
+        const found = msg.match(/https:\/\/accounts\.google\.com\/o\/oauth2\/v2\/auth\?[^\s]+/);
+        if (found?.[0]) {
+          authUrl = found[0];
+        }
+      },
+      note: async () => {},
+      prompt: async () => {
+        const state = new URL(authUrl).searchParams.get("state");
+        return `${"http://localhost:8085/oauth2callback"}?code=oauth-code&state=${state}`;
+      },
+      progress: { update: () => {}, stop: () => {} },
+    });
+
+    expect(result.projectId).toBe("env-project");
+    expect(requests.filter((url) => url.includes("v1internal:loadCodeAssist"))).toHaveLength(3);
+    expect(requests.some((url) => url.includes("v1internal:onboardUser"))).toBe(false);
+  });
+});
diff --git a/extensions/google-gemini-cli-auth/oauth.ts b/extensions/google-gemini-cli-auth/oauth.ts
index bba4c6b1f39..7e2280b9c9f 100644
--- a/extensions/google-gemini-cli-auth/oauth.ts
+++ b/extensions/google-gemini-cli-auth/oauth.ts
@@ -2,7 +2,7 @@ import { createHash, randomBytes } from "node:crypto";
 import { existsSync, readFileSync, readdirSync, realpathSync } from "node:fs";
 import { createServer } from "node:http";
 import { delimiter, dirname, join } from "node:path";
-import { isWSL2Sync } from "openclaw/plugin-sdk";
+import { fetchWithSsrFGuard, isWSL2Sync } from "openclaw/plugin-sdk";
 
 const CLIENT_ID_KEYS = ["OPENCLAW_GEMINI_OAUTH_CLIENT_ID", "GEMINI_CLI_OAUTH_CLIENT_ID"];
 const CLIENT_SECRET_KEYS = [
@@ -13,7 +13,15 @@ const REDIRECT_URI = "http://localhost:8085/oauth2callback";
 const AUTH_URL = "https://accounts.google.com/o/oauth2/v2/auth";
 const TOKEN_URL = "https://oauth2.googleapis.com/token";
 const USERINFO_URL = "https://www.googleapis.com/oauth2/v1/userinfo?alt=json";
-const CODE_ASSIST_ENDPOINT = "https://cloudcode-pa.googleapis.com";
+const CODE_ASSIST_ENDPOINT_PROD = "https://cloudcode-pa.googleapis.com";
+const CODE_ASSIST_ENDPOINT_DAILY = "https://daily-cloudcode-pa.sandbox.googleapis.com";
+const CODE_ASSIST_ENDPOINT_AUTOPUSH = "https://autopush-cloudcode-pa.sandbox.googleapis.com";
+const LOAD_CODE_ASSIST_ENDPOINTS = [
+  CODE_ASSIST_ENDPOINT_PROD,
+  CODE_ASSIST_ENDPOINT_DAILY,
+  CODE_ASSIST_ENDPOINT_AUTOPUSH,
+];
+const DEFAULT_FETCH_TIMEOUT_MS = 10_000;
 const SCOPES = [
   "https://www.googleapis.com/auth/cloud-platform",
   "https://www.googleapis.com/auth/userinfo.email",
@@ -216,6 +224,38 @@ function generatePkce(): { verifier: string; challenge: string } {
   return { verifier, challenge };
 }
 
+function resolvePlatform(): "WINDOWS" | "MACOS" | "LINUX" {
+  if (process.platform === "win32") {
+    return "WINDOWS";
+  }
+  if (process.platform === "linux") {
+    return "LINUX";
+  }
+  return "MACOS";
+}
+
+async function fetchWithTimeout(
+  url: string,
+  init: RequestInit,
+  timeoutMs = DEFAULT_FETCH_TIMEOUT_MS,
+): Promise<Response> {
+  const { response, release } = await fetchWithSsrFGuard({
+    url,
+    init,
+    timeoutMs,
+  });
+  try {
+    const body = await response.arrayBuffer();
+    return new Response(body, {
+      status: response.status,
+      statusText: response.statusText,
+      headers: response.headers,
+    });
+  } finally {
+    await release();
+  }
+}
+
 function buildAuthUrl(challenge: string, verifier: string): string {
   const { clientId } = resolveOAuthClientConfig();
   const params = new URLSearchParams({
@@ -369,9 +409,13 @@ async function exchangeCodeForTokens(
     body.set("client_secret", clientSecret);
   }
 
-  const response = await fetch(TOKEN_URL, {
+  const response = await fetchWithTimeout(TOKEN_URL, {
     method: "POST",
-    headers: { "Content-Type": "application/x-www-form-urlencoded" },
+    headers: {
+      "Content-Type": "application/x-www-form-urlencoded;charset=UTF-8",
+      Accept: "*/*",
+      "User-Agent": "google-api-nodejs-client/9.15.1",
+    },
     body,
   });
 
@@ -405,7 +449,7 @@ async function exchangeCodeForTokens(
 
 async function getUserEmail(accessToken: string): Promise<string | undefined> {
   try {
-    const response = await fetch(USERINFO_URL, {
+    const response = await fetchWithTimeout(USERINFO_URL, {
       headers: { Authorization: `Bearer ${accessToken}` },
     });
     if (response.ok) {
@@ -420,20 +464,25 @@ async function getUserEmail(accessToken: string): Promise<string | undefined> {
 
 async function discoverProject(accessToken: string): Promise<string> {
   const envProject = process.env.GOOGLE_CLOUD_PROJECT || process.env.GOOGLE_CLOUD_PROJECT_ID;
+  const platform = resolvePlatform();
+  const metadata = {
+    ideType: "ANTIGRAVITY",
+    platform,
+    pluginType: "GEMINI",
+  };
   const headers = {
     Authorization: `Bearer ${accessToken}`,
     "Content-Type": "application/json",
     "User-Agent": "google-api-nodejs-client/9.15.1",
-    "X-Goog-Api-Client": "gl-node/openclaw",
+    "X-Goog-Api-Client": `gl-node/${process.versions.node}`,
+    "Client-Metadata": JSON.stringify(metadata),
   };
 
   const loadBody = {
-    cloudaicompanionProject: envProject,
+    ...(envProject ? { cloudaicompanionProject: envProject } : {}),
     metadata: {
-      ideType: "IDE_UNSPECIFIED",
-      platform: "PLATFORM_UNSPECIFIED",
-      pluginType: "GEMINI",
-      duetProject: envProject,
+      ...metadata,
+      ...(envProject ? { duetProject: envProject } : {}),
     },
   };
 
@@ -442,29 +491,46 @@ async function discoverProject(accessToken: string): Promise<string> {
     cloudaicompanionProject?: string | { id?: string };
     allowedTiers?: Array<{ id?: string; isDefault?: boolean }>;
   } = {};
+  let activeEndpoint = CODE_ASSIST_ENDPOINT_PROD;
+  let loadError: Error | undefined;
+  for (const endpoint of LOAD_CODE_ASSIST_ENDPOINTS) {
+    try {
+      const response = await fetchWithTimeout(`${endpoint}/v1internal:loadCodeAssist`, {
+        method: "POST",
+        headers,
+        body: JSON.stringify(loadBody),
+      });
 
-  try {
-    const response = await fetch(`${CODE_ASSIST_ENDPOINT}/v1internal:loadCodeAssist`, {
-      method: "POST",
-      headers,
-      body: JSON.stringify(loadBody),
-    });
-
-    if (!response.ok) {
-      const errorPayload = await response.json().catch(() => null);
-      if (isVpcScAffected(errorPayload)) {
-        data = { currentTier: { id: TIER_STANDARD } };
-      } else {
-        throw new Error(`loadCodeAssist failed: ${response.status} ${response.statusText}`);
+      if (!response.ok) {
+        const errorPayload = await response.json().catch(() => null);
+        if (isVpcScAffected(errorPayload)) {
+          data = { currentTier: { id: TIER_STANDARD } };
+          activeEndpoint = endpoint;
+          loadError = undefined;
+          break;
+        }
+        loadError = new Error(`loadCodeAssist failed: ${response.status} ${response.statusText}`);
+        continue;
       }
-    } else {
+
       data = (await response.json()) as typeof data;
+      activeEndpoint = endpoint;
+      loadError = undefined;
+      break;
+    } catch (err) {
+      loadError = err instanceof Error ? err : new Error("loadCodeAssist failed", { cause: err });
     }
-  } catch (err) {
-    if (err instanceof Error) {
-      throw err;
+  }
+
+  const hasLoadCodeAssistData =
+    Boolean(data.currentTier) ||
+    Boolean(data.cloudaicompanionProject) ||
+    Boolean(data.allowedTiers?.length);
+  if (!hasLoadCodeAssistData && loadError) {
+    if (envProject) {
+      return envProject;
     }
-    throw new Error("loadCodeAssist failed", { cause: err });
+    throw loadError;
   }
 
   if (data.currentTier) {
@@ -494,9 +560,7 @@ async function discoverProject(accessToken: string): Promise<string> {
   const onboardBody: Record<string, unknown> = {
     tierId,
     metadata: {
-      ideType: "IDE_UNSPECIFIED",
-      platform: "PLATFORM_UNSPECIFIED",
-      pluginType: "GEMINI",
+      ...metadata,
     },
   };
   if (tierId !== TIER_FREE && envProject) {
@@ -504,7 +568,7 @@ async function discoverProject(accessToken: string): Promise<string> {
     (onboardBody.metadata as Record<string, unknown>).duetProject = envProject;
   }
 
-  const onboardResponse = await fetch(`${CODE_ASSIST_ENDPOINT}/v1internal:onboardUser`, {
+  const onboardResponse = await fetchWithTimeout(`${activeEndpoint}/v1internal:onboardUser`, {
     method: "POST",
     headers,
     body: JSON.stringify(onboardBody),
@@ -521,7 +585,7 @@ async function discoverProject(accessToken: string): Promise<string> {
   };
 
   if (!lro.done && lro.name) {
-    lro = await pollOperation(lro.name, headers);
+    lro = await pollOperation(activeEndpoint, lro.name, headers);
   }
 
   const projectId = lro.response?.cloudaicompanionProject?.id;
@@ -567,12 +631,13 @@ function getDefaultTier(
 }
 
 async function pollOperation(
+  endpoint: string,
   operationName: string,
   headers: Record<string, string>,
 ): Promise<{ done?: boolean; response?: { cloudaicompanionProject?: { id?: string } } }> {
   for (let attempt = 0; attempt < 24; attempt += 1) {
     await new Promise((resolve) => setTimeout(resolve, 5000));
-    const response = await fetch(`${CODE_ASSIST_ENDPOINT}/v1internal/${operationName}`, {
+    const response = await fetchWithTimeout(`${endpoint}/v1internal/${operationName}`, {
       headers,
     });
     if (!response.ok) {