Most of the documentation for this is dispersed. This discussion talks a bit about the validation of the method and the difference between sky view and sky exposure.
There’s also the component descriptions that you can read on the gitbook here.
This recent tutorial video describes some of the ray tracing methodologies but you will only be able to view it if you are logged in as a Ladybug Tools patron. You can also buy the video itself here:
If we get enough patrons, hopefully, I can make this video free for all.
-Chris