no, there is no description node, AFAIK the only place you can put a modle description is like the following:
<folders>
<folder>
<name>Blog</name>
<friendlyname>Blog</friendlyname>
<foldername>Blog</foldername>
<modulename>Blog</modulename>
<description>Blog Module for DNN 3.X and 4.x</description>
....
</folders>
I agree that reverse engineering isn't a great way to work these things out, but the other option was to hold up the release until all the documentation was in place. Whilst this would be ideal for dev's such as yourself, it hinders those who simply want the updated version. The documentation will be done in time, but the relevant resources are focussed on the 5.0.1/4.9.2 builds which resolve some issues that are causing users problems.
I answered the wiki question in another post of yours Geoffrey, but in simple terms, we tried the core module and found that it wasn't approriate at this time to be used, either as a wiki that the core updated but the community could view or else as a more classic wiki, hence why i'm looking into other wiki projects. Sadly, resourcing is again an issue, but we're working on it.
BTW, I believe the dnn 5 book that's coming out is written by a number of community members and does not involve any core team members or corporation staff, theres definately no aim to profit by withholding information,
Cathal