At least you can read the code, Apple's libs are closed source. You have to resort to reverse engineering techniques to fill in the documentation gaps.
Re:On Apple's Piss-Poor Documentation
by EdwardDiego on Monday November 16, 2020 @10:22PM
(#25119960)
That's a very good point. Reminds me of the bad old days of .NET (pre 2.0) where the documentation was a bit shit, and you ended up relying on Reflector to figure out wtf was going on.
If you're lucky you're getting an example or two in the README.md. The rest of the time, you're reading code to figure out the intricacies.