AT&T MERLIN Attendant System Manager's Manual page 15

Overview
Supervised Transfer
During a supervised transfer, calls are monitored by the MERLIN
Attendant until the call is completed or the caller hangs up (see Figure
1-2). When a caller enters a route or extension number, the Hold
announcement plays informing the caller to hold while the transfer is
being completed.
If the route or extension number dialed is available, the Connect
announcement informs the person at the extension dialed that a call is
being transferred. If the route or extension is unavailable, the Transfer
Fail announcement plays to inform the caller that the call could not be
completed. Sample messages are shown as follows:
1-6 Key Features
Blind Transfer Process
Figure 1-1