Tool schema converter

Convert a JSON Schema into an Anthropic tool or OpenAI function definition, and back.

AIFreeRuns in your browser

The editor opens full screen. Your files stay in your browser.

Open tool schema converter

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How it works

01
Paste a JSON Schema, an Anthropic tool or an OpenAI function.
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Pick the format you need. The tool detects what you pasted.
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Copy the converted definition and fix anything the checks flag.

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FAQ⁽³⁾

Which formats are supported?: Plain JSON Schema, Anthropic tools, OpenAI Chat Completions functions and OpenAI Responses functions.
What does strict mode do?: For OpenAI it lists every property as required and forbids extra properties, which strict function calling needs.
Is my schema uploaded?: No. The conversion runs in your browser.

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