Schemathesis website screenshot

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 8 more developer resources.

🌐 Visit website 📡 Source on GitHub
34.7/100 thin ▼ -5.2 Agent 5/100 human only Full breakdown ↓
scored 2026-07-28 · rubric v0.6
AccessFreemium
1 APIs
API TestingContract TestingFuzzingOpenAPIProperty-Based TestingSchemathesis

Kin Score

Kin Score Kin Score How this is scored →
scored 2026-07-28 · rubric v0.6
Composite quality — 34.7/100 · thin
Contract Quality 5.7 / 25
Developer Ergonomics 2.2 / 20
Commercial Clarity 7.9 / 20
Operational Transparency 4.8 / 13
Governance 8.3 / 12
Discoverability 5.9 / 10
Agent readiness — 5/100 · human only
Machine-Readable Contract 0 / 18
Agentic Access Contract 0 / 10
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
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.

Schemathesis GraphQL API

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

Pricing Plans 1

Published pricing tiers and plan structures.

Schemathesis Plans Pricing

3 plans

PLANS

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.

Schemathesis Finops

FINOPS

Semantic Vocabularies 1

JSON-LD contexts and semantic vocabularies used across these APIs.

Schemathesis Context

23 classes · 2 properties

JSON-LD

Spectral Rules 1

Spectral governance rulesets for linting and validating these APIs.

Schemathesis API Rules

5 rules · 4 warnings 1 info

SPECTRAL

JSON Schema 1

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

Schemathesis Configuration

14 properties

JSON SCHEMA

JSON Structure 1

JSON Structure definitions describing this provider's data shapes.

Schemathesis Config Structure

0 properties

JSON STRUCTURE

Examples 1

Example request and response payloads for these APIs.

Schemathesis Cli Test Example

7 fields

EXAMPLE

Security Posture 1

Authentication, domain security, vulnerability disclosure, and trust-center signals.

Schemathesis Domain Security

TLSv1.3 · DMARC

SECURITY

Resources

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

Company 3

The organization behind the API

LinkedIn
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)

apis.yml Raw ↑ 
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: '0.19'
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: 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