Tool Schema Compatibility Checker
Compare one tool input schema across OpenAI strict functions, Anthropic strict tools, Gemini functions, and MCP 2026-07-28.
Tool or input schema
Paste one JSON or YAML tool definition or raw Draft 2020-12 schema. Analysis runs in your browser.
Contract inputAnalysis results
Ready to analyze
Load an example or paste one tool definition, then choose Analyze locally.
Rules checked against
OpenAI strict function · rule pack 1.0.0 · last verified 2026-10-07
What this checks
The matrix reports documented errors and uncertainty separately. A valid Draft 2020-12 schema can still fail a provider mode. Use MCP Toolset Analyzer for whole tools/list responses.
Base schema and provider rules
Base JSON Schema Draft 2020-12 validity, wrapper validity, and provider compatibility are separate results. Undeclared schemas are explicitly treated as Draft 2020-12. External references are not fetched.
Repairs, conversion, and privacy
Only selected deterministic changes are previewed. Closing objects changes accepted values. Optional-to-required changes are never automatic. Conversion preserves the original until you choose Apply. Input and previews remain in this browser session; no provider APIs, keys, server validation, or automatic persistence are used.
Sources and limits
The selected mode displays its official documentation, rule pack version, and verification date in the results. A missing or undocumented provider rule stays uncertain. Each input is limited to 256 KiB; analysis stops after ten seconds.