The xsd documentation for pathSpecType says:

The path name, which can be a literal path name or it may include the special wildcards "", "*", and "?".

But this isn't enough information to really understand the rules around paths. For example, someone intuitively might create a path "foo/*" thinking it would match all resources under foo, but actually it matches subdirectories under foo, but not individual resources.

Ideally the semantics of ModuleXmlParser.parsePath would be documented in the pathSpecType documentation.