Gemini API Shifts from Standard to Authorization Keys

Google is transitioning Gemini API authentication from standard keys (billing-only, no caller identity) to authorization (auth) keys bound to a Cloud service account. Auth keys enable granular access control and fast leaked-key enforcement limited to the Generative Language API. All new keys created in Google AI Studio are now auth keys by default. Developers with Standard keys should create a new auth key, update GEMINI_API_KEY or GOOGLE_API_KEY in their apps, test, then revoke the old key before September 2026.