Hi @gerardo.zenobi,
If you want to add some data to a user’s auth0 profile on first login, and have it happens regardless of connection type (social vs db vs enterprise), you will have to do so in a rule. Typically customers will check for a first login flag, or some data that you would’ve added on first login, and add it then.
This thread details the difference between using a rule vs a hook.
There is a caveat when using rules vs hooks; if you create a user with the signup endpoint or through the dashboard/management API, they will not get the data until their first login. If this is an issue there are strategies to cover that case too. Let me know and we can discuss them.
Thanks,
Dan