The problem is that in the event an exception is the failure case being checked, and the output itself is not important (since any output that isn’t an exceptio

The problem is that in the event an exception is the failure case being checked, and the output itself is not important (since any output that isn’t an exception is ‘success’), that is a perfectly acceptable use case. It’s why this is a fundamentally hard problem. Some heuristics might catch 80% of the cases, but the rest? How do you even know what the real situation is, if the agent/employee/whatever you send to find out is as likely to cheat as not? It’s the classic owner/agent problem.