Writing tool definitions and schemas

Devin Osei · DEC 09, 2025 · 7 minutes
STREAM: TUTORIAL.MP4
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A good tool definition is half the battle. This guide shows how to write input and output schemas that validate cleanly, document themselves, and stay friendly to the model calling them.

We cover naming, required vs optional fields, and the small structural choices that make a tool obvious to use instead of a guessing game.

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