fix: improve error message when OAuth succeeds but project ID is required (#21070)

packages/cli/src/ui/auth/useAuth.ts

@@ -12,6 +12,7 @@ import {
   loadApiKey,
   debugLogger,
   isAccountSuspendedError,
+  ProjectIdRequiredError,
 } from '@google/gemini-cli-core';
 import { getErrorMessage } from '@google/gemini-cli-core';
 import { AuthState } from '../types.js';
@@ -143,6 +144,10 @@ export const useAuthCommand = (
             appealUrl: suspendedError.appealUrl,
             appealLinkText: suspendedError.appealLinkText,
           });
+        } else if (e instanceof ProjectIdRequiredError) {
+          // OAuth succeeded but account setup requires project ID
+          // Show the error message directly without "Failed to login" prefix
+          onAuthError(getErrorMessage(e));
         } else {
           onAuthError(`Failed to login. Message: ${getErrorMessage(e)}`);
         }