How do you test AI agents in production? The unpredictability is overwhelming.[D]

I’ve been in QA for almost a decade. My mental model for quality was always: given input X, assert output Y. Now I’m on a team that’s shipping an LLM-based agent that handles multi-step tasks. I genuinely do not know how to test this in a way that feels rigorous. The thing works. But the output isn’t deterministic. The same input can produce different reasoning chains across runs. Hell even with temp=0 I see variation in tool selection and intermediate steps. My normal instincts don’t map here. I can’t write an assertion and run it a thousand times to track flakiness.