[oXygen-user] An example of xd documentation in xquery?

I'm doing a bit of xquery work and I want to take advantage of the excellent xd documentation facilities but I don't see an example of how to add the content to an xquery document. In a new XSLT document I know I need to add the namespace, then I can go and add <xd:doc> elements, but in XQuery I don't know how to do the equivalent. Can someone share an example xquery file with embedded doc? Thanks, Steve