Looking for docs on libapt

[Debian Linux User <erik@bossa.org>]

Hello,

 I am in the planning stage of (yes, another...) attempt to build a
GUI for apt. I had originally planned on simply doing system() calls
for install functions and providing my own parses for dependancy 
resolutions by parsing the various status files - however, on examining
the sources for apt and dpkg I realized that apt has a great deal more
to offer than I had thought. There appear to be a number of classes
available in the library and I was wondering if there is any (more
detailed) discussion of them anywhere. I have already seen the libapt-pkg-doc
material and while useful it is sparse. A concise reference to params
and returns and such is what I am looking for.

 Any such beast?

Regards,
Erik Winn