In a nutshell, the resource server is your own backend API. Except for the tokens generated and maintained by SSOfy, there is no storage for user information or other data (Client, Scopes, etc.) in SSOfy and all data is queried and verified in your own server as needed.
In other words, you have to provide endpoints and configure your application in SSOfy to point to your urls.
You should provide endpoints for the following resources:
You MUST generate a signature for your response and include it in the response headers.