Lesson 1: What the model brings, and where it slips
21 min read·13 Oct 2026
Module 2 · Lesson 1 · About 40 minutes · Needs: Module 1 (model calls, system messages, structured output, token cost)
The situation
It is Monday 13 April 2026, week 1. Priya wants to know what the model in the returns desk can be trusted with. Sam asks the sharper question: what happens when a customer argues?
This lesson answers both with one request, R-1002. Tom Becker wants to send back order 7120, a GlowLine smart bulb 4-pack, delivered 69 days before the data date: outside the 30-day window. The model must say no, and keep saying no when Tom pushes.