It would be incredibly useful to be able to programmatically reset a triggered alarm back to green. Not for all alarms of a certain type or across all entities, but a single alarm triggered against a single individual entity.
Perhaps something like:
Set-AlarmStatus -Entity [Host/Datastore/VM/etc ID] -Alarm [AlarmID] -NewStatus "green"
or even in keeping with the current alarm manager:
$triggeredAlarmSpec = New-Object VMware.Vim.TriggeredAlarmSpec
$triggeredAlarmSpec.Entity = [EntityId]
$triggeredAlarmSpec.Alarm = [AlarmId]
$alarmMgr.ResetAlarm($triggeredAlarmSpec,[newStatus])