The endterm attribute is mainly useful when the toolchain does not support
automatic link target text generation for a particular situation.  In  the
past, this was required by the man page tools for all reference page links,
but that is no longer the case, and it now actually gets in the way of
proper automatic link text generation.  The only remaining use cases are
currently xrefs to refsects.

This doesn't do any remote or external things yet, but it gives modules
like plproxy and dblink a standardized and future-proof system for
managing their connection information.

Martin Pihlak and Peter Eisentraut