Disclaimer: I’ve only worked on this for a short amount of time today.
I forked IntelliDocs to Intellitip which makes use of the new tooltip API to display function documentation under the cursor.
It’s probably full of memory leaks, the tooltip is redrawn every time you move the cursor and it doesn’t use any scopes, so comments and strings will display a tooltip too if you use a word.
There are a bunch of open issues for ways to improve it.
I’d love to rewrite it from scratch, threaded, using some kind of documentation API, nice extensibility, highlight active param etc.