The Cargo web site documentation has a page for each container (see http://cargo.codehaus.org/Containers). It's very hard to keep the information on those pages accurate as the code evolves. Thus generate them automatically using Cargo's introspection API.
The first version can simply generate the Confluence markup language. Future solutions could be implementing a Confluence plugin or improving on the generated confluence markup language by automated the publication to Confluence using the Confluence XMLRPC API for example.