Entity actions unclear

The annotation to the EntityAction class doesn't specify if a referenced Entity (entityRef) must be previously listed in the Entities node in case we use the AddEntityAction or not. Does the new added Entity appear on the specified Position beyond the scenario scope? Or, should we list and specify beforehand all Entities, which are to be added with this action.

Also the Annotation of the class "EntityAction" is incomplete ("Defines an action that adds").
Furthermore the property descriptions need to be corrected. It's "referenced entity"