This event is fired when a user performs an attended transfer
Has the value “attended_transfer” for this event
Call ID of the call that transferee is transferred to
Parent Call ID of the call that transferee is transferred to, if any
The username of the user transferee is being transferred to, if applicable.
Either extension assigned transferTarget_user, or the E164 phone number being transferred to.
Call ID of the call that issues the transfer.
Parent Call ID in case transferer_call_id is a child call.
The username of the transferer.
The extension assigned to transferer, if any.
Call ID of the call that is being transferred.
If the call being transferred is a child call, this is the ID of the parent call it belongs to.
The username of the user being transferred, if any.
Extension assigned to transferee_user, or E164 phone number.