schemathesis/schemathesis

Health v2 · maintenance only

Adoption not part of the score

3564 stars · 223 forks observed · 2026-08-28

What it is AI-extracted, prompt v1, taxonomy v1, 2026-08-29, confidence not recorded

Schemathesis is a Python-based API testing tool that automatically generates test cases from OpenAPI and GraphQL schemas using property-based testing. It runs as a CLI or integrates with pytest to find server errors, schema violations, and stateful bugs before users do.

Use cases

• fuzz my REST API for 500 errors
• test that API responses match the OpenAPI schema
• find edge case inputs that crash my API
• run automated API tests in CI from an OpenAPI spec
• stateful API workflow testing like create then delete
• test a GraphQL API automatically
• detect validation bypasses in my API

When to choose

• you have an OpenAPI or GraphQL schema and want automated bug discovery without writing test cases
• you want property-based API testing integrated with pytest or CI/CD

When to avoid

• you need to test APIs without any schema definition
• you need manual, scripted end-to-end UI tests

Facets

cli-tool · maturity active

testing fuzzing e2e-testing cli http-client testing apis developer-tools python cli cross-platform openapi graphql property-based-testing api-testing hypothesis pytest swagger stateful-testing automation

Member repositories

For agents

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