Is there no way to read relationships cross-definition? For for instance;

book:1#reader@role:1#member
movie:1#reader@role:1#member

Providing

role:1#member

, I'd like to get a list,

book:1#reader, movie:1#reader

There is the

ReadRelationships

method, but that forces me to provide a resource type. The workaround is to make a ReadRelationships RPC for each resource type, but it'd be great to be able to omit that and just get a full list