Add 'invitee' field

content/client-server-api/modules/voip_events.md

@@ -69,6 +69,19 @@ track.
 A client may send other streams and tracks but the behaviour of the other party
 with respect to presenting such streams and tracks is undefined.
 
+##### Invitees
+The `invitee` field should be added whenever the call is intended for one
+specific user , and should be set to the Matrix user ID of that user. Invites
+without an `invitee` field are defined to be intended for any member of the
+room other than the sender of the event.
+
+Clients should consider an incoming call if they see a non-expired invite event where the `invitee` field is either
+absent or equal to their user's Matrix ID, however they should evaluate whether or not to ring based on their
+user's trust relationship with the callers and/or where the call was placed. As a starting point, it is
+suggested that clients ignore call invites from users in public rooms. It is strongly recommended that
+when clients do not ring for an incoming call invite, they still display the call invite in the room and
+annotate that it was ignored.
+
 ##### Glare
 
 "Glare" is a problem which occurs when two users call each other at

data/event-schemas/schema/m.call.invite.yaml

@@ -36,6 +36,10 @@
                 "lifetime": {
                     "type": "integer",
                     "description": "The time in milliseconds that the invite is valid for. Once the invite age exceeds this value, clients should discard it. They should also no longer show the call as awaiting an answer in the UI."
+                },
+                "invitee": {
+                    "type": "string",
+                    "description": "The ID of the user being called.",
                 }
             },
             "required": ["call_id", "offer", "version", "lifetime"]