Manifest is a documentation tool for semi-automatically documenting Common Lisp packages as a set of web pages. It was written by Peter Seibel and can be installed via Quicklisp.

From the README: (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.

You can see it in action in this Video.