How to know a user is authenticated from different site

I have second site that needs (auth0) authentication info from the first site.
I already created an API on the first site with this response:

    authenticated: boolean,
    user_data: Object | null

When the second site fetch the endpoint the authenticated is false while this is fine on the first site, authenticated is true and I got the user data.
Is this because session related stuff?
Any workaround on this?

Hi @handikadwi7

I am not sure what you are trying to do, but I don’t think that is the right approach.

Instead, use SSO (Single Sign-On).
Your second site will use SSO to automatically log the user in, if they have already authenticated to the first site.