AI 101

Tool use

Sketch: the engine sends a tool request to the wheels; then the harness runs the tool and the result returns.

Tool use is when an AI model asks the app to do an action, like searching the web or running code, then reads the result.

Think of it like this: Tools are the wheels: how the car touches the world. The engine sends a request, the harness turns the wheels, and the result comes back.

Source:

https://platform.claude.com/docs/en/agents-and-tools/tool-use/overview (checked Oct 15, 2026)
https://developers.openai.com/api/docs/guides/function-calling (checked Oct 15, 2026)

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