1.

- "Gone" - "AttendedTransfer" => A call is warm transferred. The original call is gone

- "Gone" - "Supervising" => A supervising call leg is established

- "Gone" - "Conference" => A call is merged to a 3-way conference call. The original 2-way call is gone.

I am not aware of the "Gone" - "Pickup" and "Undefined" though.

2. A 3-way conference call made by the RC app is a bridge call. It has the origin type

 "origin": {

        "type": "Conference"

 }

And it has the sessionId=0. The conference (bridge) call has the telephonySessionId and it is referenced in the peerId object.

"peerId": {

    "telephonySessionId": "s-a0dd888305b18z18c590772c3z13204cb0000",

    "sessionId": "0",

    "partyId": "p-a0dd888305b18z18c590772c3z13204cb0000-2"

},

Phong,

thank you so very much for your prompt reply! Two follow up questions. When you say the original call is gone, we can still construct the original call using the previous events in the session, correct? For example, a call takes place as normal however, event 8 of the session is Gone (Attended Transfer), we can still construct the original call with events 1-7, correct? When we detect a transfer, how can we tell the new numbers involved in the call? For example, if 404-809-6345 calls 104 and then gets transfered to 106, how can we tell from the event the new number involved in the call? I see on a transfer, the peerId object has a new session id, will that new session be sent to us via webhook with the next leg of the call? Hopefully that makes sense.