Structured Output Schema Builder
Generate OpenAI, Anthropic, MCP, or plain JSON Schema wrappers from sample output
Outputs the `text.format` JSON Schema object for OpenAI Structured Outputs, with `strict: true` and object schemas locked down.
Sample JSON
Generated Output
The schema is generated entirely in your browser from the sample you paste here. No provider APIs or server-side processing are involved.
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Frequently Asked Questions
It turns a sample JSON document into either a plain JSON Schema or a provider-ready wrapper for OpenAI Structured Outputs, Anthropic tool input_schema, or MCP inputSchema definitions.
No. The builder runs entirely in your browser. It never calls OpenAI, Anthropic, or any other API.
OpenAI Structured Outputs require object schemas to explicitly disallow undeclared keys when you want strict schema enforcement. The builder applies that automatically in the OpenAI preset.
Yes. The generated output is just JSON. Copy it into your codebase or another editor and tighten enums, descriptions, optional fields, or nested constraints as needed.