Retool Portals - get auth token

Hi! I am using Retool Portals and I would like to know if it is possible to get any auth token generated by Retool (be it from a email/password login or Google SSO), so that I can send such token to my API and authenticate the user without adding add additional steps for them.

Is it possible? And if so, how to verify that such token is indeed valid in my backend?