Schemathesis: Catch API bugs before your users do

Schemathesis automatically generates thousands of test cases from your OpenAPI or GraphQL schema and finds edge cases that break your API.

• 💥 500 errors that crash your API on edge case inputs
• 📋 Schema violations where your API returns different data than documented
• 🚪 Validation bypasses where invalid data gets accepted
• 🔗 Integration failures when responses don't match client expectations

$ uvx schemathesis run http://example.schemathesis.io/openapi.json

Run Schemathesis tests in CI/CD pipelines:

- uses: schemathesis/action@v3
 with:
 schema: 'https://example.schemathesis.io/openapi.json'