ContextResource

I want to add something to "data-nl-expr="/context" . Note: I understand the concept of TargetData and Resource extension, but problem is , by adding anything to cusResource or .TargetData is , newly added attributes gets added as "data-nl-expr="/context/<cusResource>/<cusAttribute>" , however I wanted my "cusAttribute", to be available under "data-nl-expr="/context/<cusAttribute>", instead of "data-nl-expr="/context/<cusResource>/<cusAttribute>"