Lesson 6: Shipping model, prompt and config changes safely

Module 10 · Lesson 6 · About 50 minutes · Needs: Module 2 lesson 2 (the quality bar and evals/quality_gate.py) and Module 7 lesson 4 (testing an upgrade). No key and no model calls

The situation

Week 10. On 29 September the Ask prompt changed from v7 to v8 for every user at once, and nobody linked it to the cost rise until Ana asked. Helen wants a pipeline that would have caught it. Funmi asks how to undo a prompt without redeploying. Gareth asks what a staging test proves about production.

The running example is that release, cut as a bundle: prompt ask-v8 (700 system tokens) and config cfg-12 (12 chunks, not 8), on the unchanged model groq:openai/gpt-oss-20b.