OpenAI Function / Tool Schema Builder

Build OpenAI function-calling (tool-use) JSON schemas visually. Add parameters with types, descriptions, required flags, enum constraints. Output is ready to pass to chat.completions.create({tools: [...]}). Compatible with strict mode (strict: true) — emits the required additionalProperties: false.

How to use the OpenAI Function / Tool Schema Builder

Name the function, write a description, add parameters one at a time. For each parameter set type, description, whether required, optional enum constraints. The generated schema follows OpenAI's function-calling spec and works with both legacy function_call and modern tools array.