The gdbus-codegen tool generates documentation from the XML introspection
description of a D-Bus interface. Currently, only DocBook is supported at
the moment, but not every modern documentation generator can handle that
format. The reStructuredText format is a bit more well-supported,
especially in documentation generators for non-C languages.
Unlike DocBook, we get to make our own structure and conventions for how
we structure the documentation when using reStructuredText.