Guardrails and evaluation

Without an evaluation set you cannot tell an improvement from a regression. Guardrails then enforce the limits your evaluation exposed.

What this lesson covers

• Build a small, honest evaluation set early
• Score changes against it before shipping
• Enforce boundaries the model must not cross

This lesson sits in Tool Calling and Agents, part of Building AI Apps with LLMs. It assumes what came before it and leads directly into the next lesson in the module.