In the interest of moving it forward, I merged DM-35939 before fixing all the "Unknown" parameter/return type fields that the Doxygen->numpdoc converter made. There's not a lot of them, but figuring out the right types can be slow. It would be worthwhile to try to identify and fill in empty types, too (I caught a few in Returns statements): those might be harder to just search for though.

This might be a good pair coding exercise, especially paring two developers with more and less experience, to help someone gain familiarity with our types.