Api Contract Validator

What it does

The API Contract Validator ensures your API implementation stays perfectly in sync with its OpenAPI/Swagger specification. It acts as a guardrail for your API ecosystem, catching schema mismatches, linting errors, and accidental breaking changes before they disrupt your frontend or mobile consumers.

Why use this skill

Manually checking that every endpoint, request body, and status code matches a YAML file is error-prone and tedious. This skill automates that process by:

• Linting: Validating that your spec follows industry standards using Spectral or Redocly.
• Runtime Checks: Verifying real server responses against the spec using Dredd or language-specific middleware.
• Diffing: Analyzing changes between spec versions to flag breaking changes like removed fields or changed types.
• CI/CD Integration: Providing ready-to-use configurations for GitHub Actions and GitLab CI.

Supported Tools & Frameworks

It supports the most popular ecosystems out of the box, including Spectral, Redocly, oasdiff, and Dredd. For implementation-specific validation, it provides guidance for Express (Node.js), FastAPI/Flask (Python), and Go. The skill produces actionable reports, JUnit XML for CI pipelines, and markdown diffs that clearly highlight exactly what changed in your API contract.