You can only read user metadata from the client app that you have configured on the App Services application.
You can configure the :ref:`user metadata <user-metadata>` you request from an authentication provider. You do this directly on the authentication provider's configuration. For more details on which metadata fields you can use, see the provider details:
- OAuth 2.0 (:ref:`Facebook <facebook-authentication>` & :ref:`Google <google-authentication>`)
- :ref:`Custom JWT <custom-jwt-authentication>`
You can change which metadata fields you have configured by :ref:`editing the provider's configuration <configure-user-metadata-on-the-backend>`.