Subject: AQ. API key returning 401 ACCESS_TOKEN_TYPE_UNSUPPORTED on Generative Language API

Gemini API
1

Hi Google AI Team,

I generated an API key via Google AI Studio using the default project setup, and it was issued with the new AQ. prefix. When sending requests via @googlegoogle/genai SDK or cURL, the gateway fails with a 401 UNAUTHENTICATED error.

Project Details:
• Project Name / ID: 6458005016..
• Credential Type: Authorization Key (AQ.)

Request Details:
• Endpoint: POST https://generativelanguage.googleapis.com/v1beta/models/gemini-2.5-flash:generateContent
• Transport Header: x-goog-api-key

Exact Error:
HTTP 401 UNAUTHENTICATED
Reason: ACCESS_TOKEN_TYPE_UNSUPPORTED
“Request had invalid authentication credentials. Expected OAuth 2 access token, login cookie or other valid authentication credential.”

Could an engineer please check my project and sync the gateway so that AQ. authorization keys authenticate properly?

Thank you!

2

Hi @Krishna_Karale, this 401 ACCESS_TOKEN_TYPE_UNSUPPORTED error occurs because older client tools or extensions do not yet support the updated “AQ.” API key format. Please update your Kilo Code extension to the latest version supporting standard AQ API key header passing, or configure custom HTTP headers (x-goog-api-key). If you are still facing this issue after updating, please let us know.