MCP Jest

What is mcp-jest?

mcp-jest is a testing framework for Model Context Protocol (MCP) servers – like Jest, but for MCP. It provides automated testing, instant feedback, and CI/CD integration for MCP servers built in any language.

How to use mcp-jest?

Install via npm install mcp-jest (or globally with npm install -g mcp-jest), then either call the mcpTest function from your code or use the mcp-jest CLI command with a server command and list of tools to test. For example: mcp-jest node ./server.js --tools search,email.

Key features of mcp-jest

• Dead simple API – one function call tests your entire server.
• Declarative testing – describe what to test, not how.
• Comprehensive coverage – connection, capability discovery, functional, and validation.
• CI/CD ready – works with GitHub Actions, Jenkins, and more.
• Fast execution – complete suites in under 500ms.
• Zero dependencies beyond the official MCP SDK.
• Flexible usage – library, CLI, config files, TypeScript support.

Use cases of mcp-jest

• Development: test changes instantly during development.
• CI/CD: automated testing in build pipelines.
• Deployment: verify servers work before going live.
• Monitoring: regular health checks in production.
• Documentation: ensure examples actually work.