kumomta/docs/reference/message/num_attempts.md

message:num_attempts()

{{since('dev')}}

This method returns the number of delivery attempts that have been made for this message.

Each time a delivery attempt is made for a message, an internal attempt counter is incremented by one.

!!! note The number of attempts is not persistently spooled with the message, in order to reduce the IOPS impact of a large number of transient delivery attempts. The counter is stored in memory instead. If you restart kumod then an approximation of the number of attempts will be inferred when the message is spooled in, based on its age and the delivery parameters of the corresponding scheduled queue.