fix: align antigravity model discovery request headers

src/server/services/modelService.discovery.test.ts

@@ -548,8 +548,14 @@ describe('refreshModelsForAccount credential discovery', () => {
       method: 'POST',
       headers: expect.objectContaining({
         Authorization: 'Bearer antigravity-access-token',
+        Accept: 'application/json',
+        'Content-Type': 'application/json',
+        'User-Agent': 'antigravity/1.19.6 darwin/arm64',
       }),
     });
+    const discoveryHeaders = undiciFetchMock.mock.calls[0]?.[1]?.headers as Record<string, string>;
+    expect(discoveryHeaders).not.toHaveProperty('X-Goog-Api-Client');
+    expect(discoveryHeaders).not.toHaveProperty('Client-Metadata');
     expect(JSON.parse(String(undiciFetchMock.mock.calls[0]?.[1]?.body || '{}'))).toEqual({
       project: 'project-demo',
     });

src/server/services/modelService.ts

@@ -23,12 +23,10 @@ import { getCodexOauthInfoFromExtraConfig, isCodexPlatform } from './oauth/codex
 import { buildOauthInfo, getOauthInfoFromExtraConfig } from './oauth/oauthAccount.js';
 import { CLAUDE_DEFAULT_ANTHROPIC_VERSION } from './oauth/claudeProvider.js';
 import {
-  ANTIGRAVITY_CLIENT_METADATA,
   ANTIGRAVITY_DAILY_UPSTREAM_BASE_URL,
-  ANTIGRAVITY_GOOGLE_API_CLIENT,
+  ANTIGRAVITY_MODELS_USER_AGENT,
   ANTIGRAVITY_SANDBOX_DAILY_UPSTREAM_BASE_URL,
   ANTIGRAVITY_UPSTREAM_BASE_URL,
-  ANTIGRAVITY_USER_AGENT,
 } from './oauth/antigravityProvider.js';
 import {
   GEMINI_CLI_GOOGLE_API_CLIENT,
@@ -367,9 +365,7 @@ async function discoverAntigravityModelsFromCloud(input: {
           Authorization: `Bearer ${accessToken}`,
           Accept: 'application/json',
           'Content-Type': 'application/json',
-          'User-Agent': ANTIGRAVITY_USER_AGENT,
-          'X-Goog-Api-Client': ANTIGRAVITY_GOOGLE_API_CLIENT,
-          'Client-Metadata': ANTIGRAVITY_CLIENT_METADATA,
+          'User-Agent': ANTIGRAVITY_MODELS_USER_AGENT,
         },
         body: JSON.stringify(requestBody),
       }),

src/server/services/oauth/antigravityProvider.ts

@@ -15,6 +15,7 @@ export const ANTIGRAVITY_DAILY_UPSTREAM_BASE_URL = 'https://daily-cloudcode-pa.g
 export const ANTIGRAVITY_SANDBOX_DAILY_UPSTREAM_BASE_URL = 'https://daily-cloudcode-pa.sandbox.googleapis.com';
 export const ANTIGRAVITY_GOOGLE_API_CLIENT = 'google-cloud-sdk vscode_cloudshelleditor/0.1';
 export const ANTIGRAVITY_USER_AGENT = 'google-api-nodejs-client/9.15.1';
+export const ANTIGRAVITY_MODELS_USER_AGENT = 'antigravity/1.19.6 darwin/arm64';
 export const ANTIGRAVITY_CLIENT_METADATA = '{"ideType":"IDE_UNSPECIFIED","platform":"PLATFORM_UNSPECIFIED","pluginType":"GEMINI"}';
 export const ANTIGRAVITY_INTERNAL_API_VERSION = 'v1internal';
 export const ANTIGRAVITY_ONBOARD_POLL_INTERVAL_MS = 2_000;