Looks like I am missing something simple - how do I know what fields to expect in responses or in the JSON delivered to an HTTP end point? I see examples but no real documentation of the return type content structure. I was really expecting a documentation which told me what fields (nested etc) will always be there, which may or may not be there and what kind of dynamism to expect in the response. Example does not really cut it.
How do I find out complete (as much as reasonable) type information of a response (or an HTTP push)?