[Freeswitch-users] mod_callcenter record template

In mod callcenter.conf.xml there is: <param name="record-template" value="$${base_dir}/recordings/sales/${strftime(%Y-%m-%d-%H-%M-%S)}.${destination_number}.${caller_id_number}.${uuid}.wav"/> This names the file with callers number and callcenter's assigned number. Bit how to include in the file name the agent's number, which responded? Which variable to use?