Messaging error code.
Human-readable error description.
Messaging user id of the user that initiated the event.
MessengerAction which is the reason the event was triggered.
Messenger request UUID. There's no requestUuid only in EventHandlers.RetransmittedEvent and in EventHandlers.ErrorEvent when the actual request has not been made due to an invalid payload.
UNIX timestamp (seconds) that specifies the time the event was dispatched by the cloud.