Shift-left API Integration
Auto-fix integration drift before integration
Specmatic turns API specifications into executable contracts, continuously verifying that every change made by AI coding agents and engineers stays true to the desired behaviour.
Ship AI-ready APIs 10x faster, from intent to implementation, with Spec-Driven API Development.
Get started with SpecmaticOne specification, every stage of the API lifecycle
Design, build, test and govern high-quality, AI-ready APIs at scale. Drive every stage of the API lifecycle from the same API specifications, turning OpenAPI/Swagger, Arazzo, AsyncAPI, GraphQL, gRPC and WSDL into executable contracts.
Agree on the desired behaviour in a specification. Use it to test your implementation and mock its dependencies while teams build independently. Verify changes locally and in CI so integration drift is caught and corrected before services come together.
Learn how executable contracts work · Explore supported specifications and protocols
Choose your starting point
Genie — Design from intent
Your AI-native API designer. Go from an idea to AI-ready API specifications with Genie. Start with the behaviour you want your API to deliver and make the specification the foundation for implementation, testing and mocking.
Explore Genie Open GenieSkeptic — Validate your specifications
Your API linter. Validate API specifications and examples before they shape your implementation. Skeptic checks OpenAPI specifications for structural and semantic issues, with built-in and custom rules you can run locally and in CI.
Explore Skeptic Lint your first specificationStudio — Test and mock visually
Your visual workspace for spec-driven contract testing and mocking. Use Studio to configure and run contract tests and work with mocks from your API specifications. Verify that implementations honour the contract while consumers develop against the same intended behaviour.
Start the Studio tutorial Open StudioInsights — Govern continuously
Your continuous governance control plane for optimising your API ecosystem. Understand how APIs are implemented, tested, consumed and connected. Insights brings contract adoption, coverage and dependencies into a shared view so teams can identify gaps and guide improvements across services.
Explore Insights Open InsightsBring executable contracts into your development workflow
Work locally and in CI
Run contract tests and start mock servers from the command line. Use the same specifications during development and in your CI pipeline to check every change against the agreed behaviour.
CLI quick start · Contract testing · Service virtualization · CI integration
Give AI coding agents contract feedback
Connect your coding agent to Specmatic through its MCP server to run contract tests, manage mocks and check backward compatibility from an agent session. Use that feedback to correct implementation drift against the specification.
Verify your MCP servers
Check MCP servers against their declared input and output schemas to catch mismatches that can break agent integrations.