I noticed that when doAutoCompleteXXXXX methods have optional parameters (using @QueryParameter and optionaly @RelativePath, no checkDependsOn attributes (or an equivalent for auto-complete) are generated in the HTML.

Of course on the client side, there is currently no code supporting this as well, the ac.generateRequest function will have to be updated to fetch the values of the dependencies and append them to the url, like the check behavior does (see the registerValidator function).