i would not worry too much about the space the doc takes. i think putting your double thing there sounds ok to me. the one really big benefit i see from proper annotation is that tools like phpstorm can really highlight you any place you could run into fatal errors because no such method and such things. without the annotations, everything is marked as unknown (yellow in phpstorm) and you don't see the actual issues. i fixed quite a few bugs in the last months because of such hints by phpstorm.