For those curious, here are the relevant specified fields along with the relevant standards (both IETF, OIDC, etc)

JWT: https://www.iana.org/assignments/jwt/jwt.xhtml

JOSE: https://www.iana.org/assignments/jwt/jwt.xhtml

This is actually really funny because I recently had this problem having to authenticate an internal repo with an OIDC but the script had to run so early in the bootstrap processes that the python google sdk is not yet installed so I had to manually install the SDK before apt is available by pulling it down manually to bootstrap the chicken or the egg problem. My initial implementation was using curl but folks insisted (rightly) on using the official SDK. I'm sure it's a lot more than 30kb though not during runtime per say.