$hook
$hook : string
Action's hook.
Class ActionScheduler_NullAction
$hook : string
Action's hook.
$args : array<string,mixed>
Action's args.
$schedule : \ActionScheduler_Schedule
Action's schedule.
$group : string
Action's group.
$priority : int
Priorities are conceptually similar to those used for regular WordPress actions.
Like those, a lower priority takes precedence over a higher priority and the default is 10.
Unlike regular WordPress actions, the priority of a scheduled action is strictly an integer and should be kept within the bounds 0-255 (anything outside the bounds will be brought back into the acceptable range).