A recent commit (vehicle-lang/vehicle@3e199f8#diff-2260b9349eaa4e694258b188e82035a03b89a6597b0cecb52aa66c827390f2e6) updated the BNFC grammar to move resource keywords out of the declaration and into their own annotations, and also added a @property annotation. See MNIST example for full list of examples.
I've tried fiddling with the TM grammar myself, but don't understand what the ?x means and everything I do seems to break it 😄