Tool/Function-Calling Schema Builder — Free & Secure | werkzeuge

Define a function-calling tool once and export it simultaneously for OpenAI, Anthropic and Gemini — with live validation and import of any of the three formats. 100% in your browser; nothing is transmitted.

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Define a function-calling tool once — name, description and typed parameters (incl. enums, arrays and nested objects) — and export it simultaneously for OpenAI, Anthropic and Gemini. Existing definitions can be imported and normalised.

Tool / function name Description

Strict mode (OpenAI + Anthropic) OpenAI Responses format (flat)

Sets "strict: true" for OpenAI and Anthropic. OpenAI additionally requires every property to be in "required" — so optional fields are encoded as nullable-and-required (a type union with "null"). Anthropic keeps genuine optional fields. Gemini has no strict mode and is always a best-effort projection.

Parameters

No parameters yet — add one.

Dropped/adjusted for Gemini:

Import normalisation notes:

Building agents and tool calling for production? The vAudience nexus platform orchestrates tools across OpenAI, Anthropic and Gemini.

Agent tools: MCP Config Generator · AGENTS.md Generator

Import a tool definition

Paste an OpenAI, Anthropic or Gemini tool definition. The format is detected automatically.

⚠ This will replace your current definition.

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