Hello,
  I understand that one way to run a rest based XQuery with parameters is to use the following ...
  http://localhost:8984/rest/DB/mult.xq?a=21&b=2

  This is possible if the query is in the BaseX database.

   I need to use REST, but the query file (.xq) and .xqm, .xsl files need to be located on the server but not in the database.

  Can someone give me a pointer about how to do that?

Thanks,
Anupam