Lesson 2: Debugging a run: replay it, find the step, name the fault
31 min read·13 Oct 2026
Module 14 · Lesson 2 · About 75 minutes · Needs: Module 5, Lesson 1 (the loop and ScriptedModel) and Module 13 (the careful plans)The situation
It is Tuesday 23 June 2026, week 11. This morning a prompt change shipped without the eval gate. Within hours the agent was handing far more requests to people, Priya noticed, and Dev rolled back to the previous version. Now three people want answers. Priya asks why it happened and how she would know sooner. Marta asks whether money moved. Aisha Rahman has written in: she asked about returning her kettle (R-1003, order 5730, $39.00), which has not arrived yet, and was told a person would contact her. The agent could have answered her itself.
You will trace Aisha's run all lesson. Every run and number below is simulated, from scripted models.