Ideas for devices generating a lot of alerts

I think LM's solution would be to sell you Dexda, although I haven't used it myself and is limited to ServiceNow integration last I checked.

For us, all alerts all go into a ticketing system, so in general we would run reports thru the ticketing system looking for that kinda thing, but that is more of a manual process.

Regarding an issue with using API to query alert history. That sounds doable to me but I would implement something like that as an EventSource rather then as a DataSource. EventSources automatically clear themselves after a set time you set.