schema

Code rolled back and the database did not. The old version is now running against a schema it has never seen, and that is a worse incident than the one you were trying to end.

Asking nicely in the prompt gets you most of the way and fails on the tail, which is where the automation breaks. Constrained decoding can guarantee the shape of completed output for supported schemas. Interrupted generations still need a failure path, and compilation has a latency cost.