Skills, MCP, and Deterministic Computation

This chapter covers three related ways to extend an agent without bloating its context or trusting it to do things it is bad at: skills (packaged expertise loaded on demand), MCP (a standard protocol for plugging in external tools), and deterministic computation (the discipline of pushing exact work into code instead of the model's head). They share a theme: keep the model focused on reasoning, and let well-structured external pieces handle the rest.