NEW in v1.0.13

HTTP Transport Support

Test MCP servers over HTTP streaming and Server-Sent Events (SSE) connections, in addition to the default stdio transport.

Available Transports

stdio

Default transport. Starts and communicates with your server via stdin/stdout.

streamable-http

HTTP streaming transport for servers that expose an HTTP endpoint.

sse

Server-Sent Events transport for real-time streaming connections.

CLI Usage

Testing stdio servers (default)

mcp-jest node ./server.js --tools search,email

Testing HTTP streaming servers

mcp-jest --transport streamable-http --url http://localhost:3000 --tools search

Testing SSE servers

mcp-jest --transport sse --url http://api.example.com/sse --tools search,email

Configuration File

For complex setups, use a JSON configuration file:

{
  "server": {
    "transport": "streamable-http",
    "url": "http://localhost:3000/mcp"
  },
  "tests": {
    "tools": ["search", "calculate"],
    "timeout": 60000
  }
}

Then run with:

mcp-jest --config mcp-jest.json

Use Cases

  • Remote servers: Test MCP servers deployed in the cloud
  • Microservices: Test servers that are part of a larger HTTP-based architecture
  • Development: Test against a running dev server without restarting
  • Production monitoring: Run health checks against live endpoints

💡 Pro Tip

HTTP transports are backward compatible - existing stdio tests continue to work without any changes.

Next: Test Filtering