Here is a overview of the other information you can get listed from prism.

listcommands A list of all commands supported by DQL
listdocuments A list of all documents found in prism. Return format is {"result" :"ok", "documents" : [{docdef},{docdef2}...]}. Each docdef contains "Current Mode", Description, "File Name", "Object Name", "Style Name" and a calulated type that tell if this is Form, Menu etc. This is information about the old style DataEase application as it is stored in "Application Objects"
listfunctions A list of all functions found in prism. Return format is {"result" :"ok", "functions" : ["name1","name2"...]}
listinternals Do all listed here except for documents
listoperators A list of all operators supported by prism. Return format is {"result" :"ok", "operators" : ["<","<="...]}
listrelated A list of all relations found for a table or relation name. Format is /definition/listrelated/relname. Return format is {"result" :"ok", "relationnames" : ["name1","name2"...]}
listtables A list of all tables found in prism. Return format is {"result" :"ok", "tables" : ["name1","name2"...]}. You can add hidden tables by showhidden=1 in query