Tool Calling

Giving LLMs the ability to interact with the world through tools.

Slides

View slides in full screen

Outline

• (30m) Tool calling
  • Demo _demos/15_demo_manual-tools: a human relays tool calls between the LLM and the functions
  • Demo _demos/16_demo_tools: the same tools, registered with ellmer or chatlas
  • Your Turn _exercises/17_quiz-game-2: register a play_sound tool (beepr in R, playsound in Python) in the Quiz Show app
  • Your Turn _exercises/18_quiz-game-3: add tool annotations to give the tool a title and an icon. The exercise points to ContentToolResult if you want richer tool displays.

Further reading

Hadley Wickham’s “What is an agent?” series on Substack explains tools, harnesses, and agents from first principles with ellmer examples:

• What is an agent? — conversations, turns, rounds, tools, and a precise definition of an agent.
• Your LLM can’t math (and that’s ok) — how tool calls actually work, and why web chats can do things a bare LLM can’t.