Schemathesis

Schemathesis is a property-based API testing tool that automatically generates test cases from OpenAPI and GraphQL schemas to find bugs and specification violations. It uses the Hypothesis property-based testing framework to generate diverse, edge-case-covering test inputs from schema constraints, detecting server crashes, response schema violations, validation bypasses, and stateful bugs in multi-step workflows. Used by Netflix, SAP, Red Hat, IBM, and JetBrains.

Schemathesis publishes 1 API on the APIs.io network. Tagged areas include API Testing, Contract Testing, Fuzzing, OpenAPI, and Property-Based Testing.

The Schemathesis catalog on APIs.io includes 1 JSON-LD context and 1 Spectral governance ruleset.

Schemathesis’ developer surface includes documentation, engineering blog, code examples, and 9 more developer resources.

🌐 Visit website 📡 Source on GitHub

22.2/100 emerging ▬ flat Agent 4/100 human only Full breakdown ↓
scored 2026-08-25 · rubric v0.14.0

AccessFreemium

1 APIs

API Testing Contract TestingFuzzingOpenAPIProperty-Based TestingSchemathesis

Kin Score

Kin Score How this is scored →
scored 2026-08-25 · rubric v0.14.0

Composite quality — 22.2/100 · emerging

Contract Quality 6.3 / 25

Developer Ergonomics 2.4 / 20

Access Clarity 3.2 / 20

Operational Transparency 1.4 / 13

Contract Governance 3.0 / 12

Discoverability 5.9 / 10

Agent readiness — 4/100 · human only

Machine-Readable Contract 0 / 18

Agentic Access Contract 0 / 10

Documented Reversibility 0 / 6

MCP Server 0 / 12

Machine-Readable Auth 0 / 10

Idempotency 0 / 9

Stable Error Semantics 0 / 8

Request/Response Examples 7 / 7

Rate-Limit Signaling 7 / 7

Typed Event Surface 0 / 6

Agent Skills 0 / 5

Well-Known Catalog 0 / 4

Consent & Bot Identity 0 / 3

A2A Agent Card 0 / 8

Dry-Run / Simulate Mode 0 / 4

Delegated User Identity 0 / 6

Protected Resource Metadata 0 / 5

Registration Without a Human 0 / 6

Agentic Commerce Surface 0 / 5

Improve this rating by publishing the missing artifacts — every area above can be raised, and the full rubric is at apis.io/rating/. This rating is computed from github.com/api-evangelist/schemathesis: open an issue to ask a question, or submit a pull request to add artifacts. Want it done for you? Prioritized profiling — $2,500 →

APIs 1

Individual APIs this provider publishes, each with its own machine-readable definition.

Schemathesis

Schemathesis is a property-based API testing tool that automatically generates test cases from OpenAPI and GraphQL schemas to find bugs and spec violations. It detects server cr...

GraphQL 1

GraphQL schemas published by this provider.

Rate Limits 1

Documented rate limits and quota policies.

Schemathesis Rate Limits

5 limits

RATE LIMITS

FinOps 1

Cost, billing, and metering signals for API financial operations.

JSON Schema 1

Standalone JSON Schema definitions for this provider's data models.

Examples 1

Example request and response payloads for these APIs.

Documentation 1

Reference material describing how the API behaves

Documentation

Documentation

Design & Contract 1

Pagination, idempotency, versioning, errors, and events

Vocabulary

Vocabulary

Build 3

SDKs, sample code, and the tooling you integrate with

GitHubOrganization

GitHubOrganization

PyPI Package

PyPI Package

Examples

Examples

Access & Security 1

Authentication, authorization, and security posture

DomainSecurity

DomainSecurity

Commercial 1

Pricing, plans, and the legal terms of use

License

License

Company 3

The organization behind the API

LinkedIn

Website

Website

Blog

Blog

Other 2

Properties that don't map to a standard resource type

Docker Image

Docker Image

Research

Research

Source (apis.yml)

aid: schemathesis
name: Schemathesis
description: Schemathesis is a property-based API testing tool that automatically generates test cases from OpenAPI and GraphQL
  schemas to find bugs and specification violations. It uses the Hypothesis property-based testing framework to generate diverse,
  edge-case-covering test inputs from schema constraints, detecting server crashes, response schema violations, validation
  bypasses, and stateful bugs in multi-step workflows. Used by Netflix, SAP, Red Hat, IBM, and JetBrains.
type: Index
accessModel:
  pricing: freemium
  onboarding: unknown
  trial: false
  try_now: false
  public: false
  label: Freemium
  confidence: medium
  source:
  - plans
  generated: '2026-07-22'
  method: derived
image: https://kinlane-images.s3.amazonaws.com/shared/apis-json/icons/schemathesis.png
tags:
- API Testing
- Contract Testing
- Fuzzing
- OpenAPI
- Property-Based Testing
- Schemathesis
url: https://raw.githubusercontent.com/api-evangelist/schemathesis/refs/heads/main/apis.yml
created: '2026-03-25'
modified: '2026-05-02'
specificationVersion: '0.23'
apis:
- aid: schemathesis:schemathesis
  name: Schemathesis
  description: Schemathesis is a property-based API testing tool that automatically generates test cases from OpenAPI and
    GraphQL schemas to find bugs and spec violations. It detects server crashes, schema violations, validation bypasses, and
    integration failures with minimal maintenance overhead—tests adapt automatically as schemas evolve.
  humanURL: https://schemathesis.io
  tags:
  - API Testing
  - Contract Testing
  - Fuzzing
  - GraphQL
  - Hypothesis
  - OpenAPI
  - Property-Based Testing
  - Python
  properties:
  - type: Documentation
    url: https://schemathesis.readthedocs.io
  - type: GitHubRepository
    url: https://github.com/schemathesis/schemathesis
  - type: PyPI Package
    url: https://pypi.org/project/schemathesis/
  - type: GettingStarted
    url: https://schemathesis.readthedocs.io/en/stable/getting-started.html
  - type: Docker Image
    url: https://hub.docker.com/r/schemathesis/schemathesis
  - type: GitHub Action
    url: https://github.com/schemathesis/action
  - type: ChangeLog
    url: https://github.com/schemathesis/schemathesis/releases
  - type: JSONSchema
    url: https://raw.githubusercontent.com/api-evangelist/schemathesis/refs/heads/main/json-schema/schemathesis-config-schema.json
  - type: JSONStructure
    url: https://raw.githubusercontent.com/api-evangelist/schemathesis/refs/heads/main/json-structure/schemathesis-config-structure.json
  - type: JSONLD
    url: https://raw.githubusercontent.com/api-evangelist/schemathesis/refs/heads/main/json-ld/schemathesis-context.jsonld
  - url: graphql/schemathesis-graphql.md
    type: GraphQL
common:
- type: License
  name: MIT
  url: https://github.com/schemathesis/schemathesis/blob/master/LICENSE
- type: DomainSecurity
  url: security/schemathesis-domain-security.yml
- type: LinkedIn
  url: https://www.linkedin.com/company/schemathesis-io
- type: Website
  url: https://schemathesis.io
- type: Documentation
  url: https://schemathesis.readthedocs.io
- type: GitHubOrganization
  url: https://github.com/schemathesis
- type: PyPI Package
  url: https://pypi.org/project/schemathesis/
- type: Docker Image
  url: https://hub.docker.com/r/schemathesis/schemathesis
- type: Blog
  url: https://schemathesis.io/blog
- type: Research
  url: https://dl.acm.org/doi/10.1145/3510003.3510097
- type: Vocabulary
  url: https://raw.githubusercontent.com/api-evangelist/schemathesis/refs/heads/main/vocabulary/schemathesis-vocabulary.yml
- type: Examples
  url: https://raw.githubusercontent.com/api-evangelist/schemathesis/refs/heads/main/examples/schemathesis-cli-test-example.json
maintainers:
- FN: Kin Lane
  email: kin@apievangelist.com

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Schemathesis

Kin Score

APIs 1

Schemathesis

GraphQL 1

Schemathesis GraphQL API

Pricing Plans 1

Schemathesis Plans Pricing

Rate Limits 1

Schemathesis Rate Limits

FinOps 1

Schemathesis Finops

Semantic Vocabularies 1

Schemathesis Context

Spectral Rules 1

Schemathesis API Rules

JSON Schema 1

Schemathesis Configuration

JSON Structure 1

Schemathesis Config Structure

Examples 1

Schemathesis Cli Test Example

Security Posture 1

Schemathesis Domain Security

Resources

Documentation 1

Design & Contract 1

Build 3

Access & Security 1

Commercial 1

Company 3

Other 2

Source (apis.yml)

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