Not sure I understand? I would say that GitHub is quite social. It's pretty much the Facebook of code hosting.

No way to hold discussions though. How social is that? How do I ask a question (which is not a bug or a feature request)? Go to some completely different site?

In general, I'd say file a bug asking for further documentation. Github supports wikis for documenting projects, which works well enough for this. For a lot of smaller projects/tools a good README.md is enough though.