Even if this will be integrated I still think it might be a bad idea for some things because it goes into the separation of concerns principle.

A controller should not know about routes.

A model should not know about database design.

Unless you want to write a ton of transformers, your models will likely know about your database design. If only by virtue of having the same properties.

I think the parent is objecting to the fact that annotations spray this "external" information right in the middle of the controller/model. FWIW, decent tools let you put this info in separate configuration files instead of code annotations, "decoupling" it from the code.