I got claude to write me an auth layer using only python http.client and cryptography. One shot no problem, now I can get a token from the service key any time, just have to track expiration. Annoying that they don't follow industry standard though.
as there are so many variations out there the AI gets majorly confused, as a matter of fact, the google oauth part is the one thing that gemini 2.5 pro cant code
Maybe you should just read the docs and use the examples there. I have used all kinds of GCP services for many years and auth is not remotely complicated imo.