On Demand Build Agents: Determine if build agent has been idle for over an hour using a program.

I know that you can look at each agent statistics and see when they were idle and when they run, but is this information available via a program?

What the higher up wants to do is to see if an agent has been idle for an hour and if it has, shut it down in AWS until it is needed again.  Of course one it is shutdown, I got to figure out how to "turn it back on" when it is needed for a build.

So basically we are wanting "on demand build agents".  Can this be done via Powershell or anything else to query this information and shutdown/startup the agents when needed?  If this can be done via REST API, can you give examples please (or links)?  I have never used REST API before.

Thank you very much.