Two separate models — one writing the code, one reviewing the diff — shipped a one-word bug to staging. Both ran local checks. Both came back green. The fix they missed was not exotic or subtle. It was written down, in plain English, in a file sitting in the same directory as the change. That last detail is the one worth staying with. This is not a story about a model being wrong. Both models were, within the job they were given, correct. It is a story about where verification stops looking —...