How do you document a REST API?

Question

How do you document a REST API? Not just the documentation of what the resources are, but really what is the data that gets sent in the request and what the data is that gets se

Answer 1

I've experience using Enunciate which is great but I don't really like the clients that you can generate with it. On the other hand, I've been using swagger on my last projects and it seems to fit my needs, it's really cool you should give a try!

UPDATE 03/08/2016: Looks like you can use Enunciate to build swagger docs.
See this.