This is the BrainML-X protocols subschema describing interactions with analysis servers. Included are a means to query an analysis server for algorithms matching certain criteria. Note: canonical location of the 'xml' schema is "http://www.w3.org/2001/xml.xsd", however sometimes this server is down or slow, so we use a local copy. Needed for 'conditions' and 'return' definitions. Query for available algorithms in server. Algorithm response.