How to verify Facebook access token?

Question

There\'s only thing that server has to do; just check any access token\'s validity.

Clients send to the server user id and access token obtained by FB.getLogin

Answer 1

Just wanted to let you know that up until today I was first obtaining an app access token (via GET request to Facebook), and then using the received token as the app-token-or-admin-token in:

GET graph.facebook.com/debug_token?
    input_token={token-to-inspect}
    &access_token={app-token-or-admin-token}

However, I just realized a better way of doing this (with the added benefit of requiring one less GET request):

GET graph.facebook.com/debug_token?
    input_token={token-to-inspect}
    &access_token={app_id}|{app_secret}

As described in Facebook's documentation for Access Tokens here.