Function Calling

Give your agent tools to interact with the world

🔑 Key Concepts

How it works — The model outputs structured JSON describing which function to call. Your code executes it and returns the result.
Tool schemas — Name, description (when to use it, not just what it does), parameter schema with types. Bad descriptions = wrong calls.
Error handling — Feed tool errors back to the model: 'The API returned 404'. Let the agent adapt and retry.
Safety — Sandbox code execution, read-only for databases, human approval for destructive actions.

💡 Practice: Try implementing each concept yourself before moving on. Reading about RAG and building RAG are very different things.