How to define cli-completion-actionpoint for the list without key

Here is a fragment of yang data model (from ietf-routing.yang):

   container routing{
       container ribs {
         list rib {
           key "name";
           leaf name {
             type string;
           }
           container routes {
             config false;
             list route {
               leaf route-preference {
                 type route-preference;
               }
               container next-hop {
                 uses next-hop-state-content;
               }
               uses route-metadata;
             }
           }
. . . 

As you can see list route does not have a key.
I want to display in CLI a list of available routes when user presses TAB after “show routing ribs ribName routes route”. However tailf:cli-completion-actionpoint requires path to actual element not to the list. So, how do I specify it?

tailf:annotate "/rt:routing/rt:ribs/rt:routes/rt:route/?????" {
   tailf:cli-completion-actionpoint  my_actpoint;
}

key-less list by definition does not have keys / key values, so imho you cannot work around and show completion…

imho, philosophically speaking - as there are no keys, there is also no way how to use them explicitly, thus no need to show them to user…