Yes, there is seemingly a lot of documentation, each part of which describing about 80% of what you need to know. They've put a lot of effort into it, I think, yet it needs more effort. Since I haven't contributed to that effort, I can't complain. My advice: just read the source code. I wish you could just read the docs and understand the semantics of every api, but I finally realized that, if I cannot google the answer to my question in 15 seconds, just open the source code, which is excellently documented (internally), and very consistent in using patterns.