Lesson 3: Give the agent new reach, and fence what it can touch
20 min read·13 Oct 2026
Module 8 · Lesson 3 · About 55 minutes · Needs: Module 8 Lesson 1 (the agent loop); Module 6 Lesson 2 (tool definitions, errors returned to the model)
The situation
It is Tuesday 21 July 2026, week 8. The refund agent handles Ana Duarte's T-1001, and three people want more from it.
Tomasz wants the billing lookups in the team's chat tool too, written once. Joel asks what Ardent Design would save a year on annual billing, which no tool answers; the quick fix is to let the agent run code. Anika asks where that code would run, and sends you a disclosure about an agent builder that ran code it was handed.