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OpenAI Structured Outputs Schema Validator

Check strict JSON Schema for OpenAI Structured Outputs. Find missing required fields, invalid root types and unsupported keywords.

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JSON Schema

Paste a schema or its Structured Outputs wrapper.

Schema findings

Paths and suggested fixes will appear here.

Check a schema before calling OpenAI

Start with an object at the root. Set additionalProperties to false on every object, and list each property in required. Use a union with null for optional values.

If properties contains title but required is empty, add title to required.

Limitations

Checks a documented subset locally. Model-specific rules and limits can require additional validation.