"Asterisk-Acc-Code", The account name of detail records
"Asterisk-CidName",
"Asterisk-CidNum",
"Asterisk-Cidani",
"Asterisk-Cidrdnis",
"Asterisk-Ciddnid",
"Asterisk-Exten",
"Asterisk-Context", The destination context
"Asterisk-Channame", The channel name
"Asterisk-Appname", Last application run on the channel
"Asterisk-App-Data", Argument to the last channel
"Asterisk-Event-Time",
"Asterisk-Event-Type",
"Asterisk-AMA-Flags", DOCUMENTATION, BILL, IGNORE etc, specified on
a per channel basis like accountcode.
"Asterisk-Unique-ID", Unique call identifier
"Asterisk-User-Field" User field set via SetCELUserField
"Asterisk-Peer" Name of the Peer for 2-channel events (like bridge)