For what it looks, this is something where DCR (https://openid.net/specs/openid-connect-registration-1_0.html https://openid.net/specs/openid-connect-registrati

For what it looks, this is something where DCR (https://openid.net/specs/openid-connect-registration-1_0.html https://openid.net/specs/openid-connect-registration-1_0.htm...) could be helpful. Some auth providers like Auth0 have support for it: https://auth0.com/docs/get-started/applications/dynamic-client-registration https://auth0.com/docs/get-started/applications/dynamic-clie.... There are some caveats and security concerns when using DCR, so you should research more into that. Another option may be CIMD (https://www.ietf.org/archive/id/draft-parecki-oauth-client-id-metadata-document-00.html https://www.ietf.org/archive/id/draft-parecki-oauth-client-i...) though I'm not totally familiar with it. What you also mentioned, like using proxys, or wildcards, is also widely used, at least for what I've seen.