DX NetOps

We are monitoring multiple wireless environments and we want to alert on the amount of access points offline.

I thought this would be a general feature, but I can only find a way to monitor the maximum amount of access points but not the minimum amount of access points.

If have done a vnmsh attributes list of a WLC, but can't find the setting.

Does anyone else build anything like this in spectrum?

So if I understand correctly, there is no option to monitor the amount of online access points? 

Does someone at least know how to retrieve the amount of online access points from spectrum? Because in that case I can build something around it that monitors the amount.

Nick