AI Agents: The Definitive Guide

Chapter 4. Models Behind the Agents: Capabilities and Optimization

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By now you have already done the hard work to understand how to design AI agents and make them better. This is the right moment for me to ask you to step back, look behind the scenes, and think more deeply about the models that make them intelligent. You might ask yourself why I didn’t introduce the models at the beginning. There is a reason. Let me tell you.

For this chapter it’s crucial to understand what you can do with your AI agents, because it completes the narrative arc of how I want you to think about them. I want you to think about your agents as if you were hiring team members. To do that well, you need the bigger picture: how your team interacts, how you structure it, and how you coach it to improve and collaborate. All of this was covered in the previous chapters.

This is my own mental model for designing AI agents. I think of agents as dynamic, collaborative systems rather than isolated components. Every model size ...