```
@Target(allowedTargets = {AnnotationTarget.CONSTRUCTOR, AnnotationTarget.ANNOTATION_CLASS}) 
public @interface OnlyForUseByGeneratedProtoCode

                    
```
Opt-in annotation to make it difficult to accidentally use APIs only intended for use by proto generated code. See https://kotlinlang.org/docs/reference/opt-in-requirements.html for details on how this API works.

Annotation OnlyForUseByGeneratedProtoCode