given a function commented like:

(:~
: return search results
: <hit>
: <entity>country</entity>
: <name>name</name>
: <url>...</url>
: </hit>
:)
declare
%rest:GET %rest:path("where4/api/search")
%restxq:query-param("q", "{$q}")
%output:method("json")
function search($q){

The wadl function [1] produces:
 
<wadl:resource path="/where4/api/search/">
      <wadl:method name="GET">
        <wadl:doc xmlns="http://www.w3.org/1999/xhtml">return search results
<hit xmlns="" xmlns="http://www.w3.org/1999/xhtml">
<entity xmlns="">country</entity>
<name xmlns="">name</name>
<url xmlns="">...</url>
</hit>
        </wadl:doc>
        <wadl:request>
          <wadl:param name="q" style="query"/>
        </wadl:request>
        <wadl:response>
          <wadl:representation mediaType="application/json"/>
        </wadl:response>
      </wadl:method>
    </wadl:resource>

Regards
/Andy

[1] http://docs.basex.org/wiki/RESTXQ_Module#rest:wadl