All fields of this step support metadata injection. You can use this step with ETL metadata injection to pass metadata to your transformation at runtime.
When using metadata injection with the Annotate Stream step, you can reuse shared annotation groups which already exist, but you cannot create a new shared annotation group. If you inject a shared annotation group by providing a value for SHARED_ANNOTATION_GROUP, then it is assumed that you are re-using an existing shared annotation group. As a result, any annotations defined in the ETL Metadata Injection step are ignored.