Comment-able documentation?

Greetings,

I’ve always admired how the Yii class reference allows users to comment on it, and how one need only sign up on the forums to do so. I similarly need to integrate PHP documentation for a sizable Yii project (using Yii’s documentation generator) with IP Board the way it is done on this website. My question then is: how is it done? I mainly would appreciate a general overview of how it’s all done, but in particular what I’m most curious about is the following:

  • Is the class reference an extension of IP Board, or a completely separate standalone web application?

  • How is the documentation inserted/updated, whether done through IP Board or a separate application?

  • If a separate application, how is the authorization data passed from IP Board to the application?

Thank you very much!