An eval suite you run once is worthless; one that runs on every change is a safety net. Enforce means wiring your evals into the development loop so every change gets measured against them automatically, and you can see a specific failure rate go up or down after a change.

This is regression testing for non-deterministic systems: it is how you ship changes with confidence instead of hoping. Observability tooling closes the loop by tracing production behaviour back into your eval set.