The Xdoc plugin is the primary mechanism used to produce the Maven-generated documentation as well as any user supplied "xdocs". An xdoc is an XML document conforming to a small and simple set of tags. Maven uses this format extensively. All Maven-generated reports are first generated as an xdoc, which is then transformed to HTML via this plugin.
The documentation is mainly in Anakia format. More information along with samples, can be found at: