About Schema Preflight

Schema Preflight is a browser-local checker for developers preparing JSON Schemas for OpenAI Structured Outputs. It looks for common strict-mode blockers such as missing required fields, missing additionalProperties: false, root shape problems, deep nesting, and risky schema keywords.

It does not call the OpenAI API, upload pasted schemas, or guarantee model behavior. This independent tool is not affiliated with OpenAI; treat the result as a preflight checklist before testing with the official API.