version 1 .

Packet = Turn / Error / Extension .

Extension = <<rec> @label any @fields [any ...]> .

Error = <error @message string @detail any>.

Assertion = any .
Handle    = int .
Event     = Assert / Retract / Message / Sync .
Oid       = int .
Turn      = [TurnEvent ...].
TurnEvent = [@oid Oid @event Event].

Assert  = <A @assertion Assertion @handle Handle>.
Retract = <R @handle Handle>.
Message = <M @body Assertion>.
Sync    = <S @peer #:#t>.