Documentation for ament_cmake_auto

I like that ament_cmake_auto can potentially eliminate a lot of boilerplate. However, I've not been able to find any documentation for it besides three examples at the bottom of this article: https://design.ros2.org/articles/ament.html. I found it not to be self-explanatory in all cases, and those examples are already five years old. Is ament_cmake_auto documented somewhere, and if not, will it be at some point in the future?