disqualifying
Annotation descriptors that mark a member as something other than a plain addition.
The injector half is ASKED of Mixin, not listed: InjectionInfo holds the registry every injector registers itself into. That covers MixinExtras' whole surface, and injector annotations a single mod declares for itself — which no list written here could have known about.
CORE_NOT_ADDED is the rest: Mixin's own vocabulary for what a member IS, which is the language of mixins rather than of injectors and does not grow with third parties.
Throws rather than degrades if the registry cannot be read — derive turns that into "no overlay", which is the safe answer: a member wrongly declared here compiles and then fails at runtime, while a missing one only costs a cast.