Another pattern, though, is that a top level tool uses pkg_resources and entry_points to move its core functionality out to verb plugins— in that case the help is actually the worst case scenario because not only do we have to scan the filesystem looking for what plugins are available, they all have to be imported in order to ask each for its help strings.

An extreme version of this is the colcon build tool for ROS 2 workspaces:

https://github.com/colcon/colcon-core/blob/master/setup.cfg#...

Unsurprisingly, startup time for this is not great.