git clone 'https://github.com/gigamonkey/manifest.git'
Manifest is a system for semi-automatically documenting Common Lisp packages. (A manifest tells you what's in a package. Also this system makes manifest a bunch of information that is actually present in a Lisp system.) The basic premise is that every exported symbol in a package should be documented.
To check it out, after loading the system, evaluate (start) and point your browser at the URL it returns.