Yeah, this is what happens when there's nothing between "the agent decided to do this" and "it happened." The agent followed the state file logically. It wasn't wrong. It just wasn't checked.

His post-mortem is solid but I think he's overcorrecting. If he does this as part of a CICD pipeline and he manually reviews every time, he will pretty quickly get "verification fatigue". The vast majority of cases are fine, so he'll build the habit of automatically approving it. Sure, he'll deeply review the first ones, but over time it becomes less because he'll almost always find nothing. Then he'll pay less attention. This is how humans work.

He could automate the "easy" ones, though. TF plans are parseable, so maybe his time would be better spent only reviewing destructive changes. I've been running autonomous agents on production code for a while and this is the pattern that keeps working: start by reviewing everything, notice you're rubber-stamping most of it, then encode the safe cases so you only see the ones that matter.