I don't think there's any notification that someone has added you to their contact list. That is, if you have someone's phone number in your contact list, and

I don't think there's any notification that someone has added you to their contact list. That is, if you have someone's phone number in your contact list, and they sign up for amazon calling, you see their name in a list. However, if they don't have your number already, they can't see you as a contact. The only information leaking is that someone can learn that you're still using the phone number they have for you and that you're using amazon calling. Contacts in amazon calling don't appear to be two way.