loose source route

Of course
there are details of a query language (how to ask questions) and

...and so its never been done? Or do you know of such
a client-server? (URL please) I think this is the way to
go myself, but don't want to re-invent.

  BTW, my experience has been that planned/scheduled outages
are the exception. The usual case being a congestion,
vendor bug, routing problem, etc. Of course there will
always be some NSP's that would never implement such a server
for business purposes.