+1 just call them class annotations. "annotation" itself already means "meta-information"
What are class properties ?
How do annotations relate to Magritte? I'm guessing Magritte descriptions are a specific kind of annotation already, right?
About #declaredInstances: you could do MySpecialAnnotation new in a playground��� but that instance would not be attached to any class. I think the point of that query is to return the annotation instances that do come from an actual class with an actual method with the <classAnnotation> pragma.
BTW, what if the method with <classAnnotation> returns a different result each time?