MCP Test Client

What is MCP Test Client?

MCP Test Client is a middleware tool that acts as both an MCP server (to Claude) and an MCP client (to servers under test), enabling developers to test MCP servers during development without registering them directly with Claude.

How to use MCP Test Client?

Install dependencies with npm install, build with npm run build, then either register the server with Claude via the claude-mcp-local script and use its exposed tools, or run the CLI interface with npm run test for an interactive testing menu.

Key features of MCP Test Client

• Deploy MCP servers to test environments
• Call individual tools with custom arguments
• Run automated test suites
• View server logs
• Test servers before formal registration with Claude

Use cases of MCP Test Client

• Develop and debug an MCP server in isolation before registration
• Deploy a server to a staging environment and call its tools
• Run end-to-end test suites against deployed servers
• Inspect server logs during development to fix issues
• Iterate on server code and redeploy quickly without affecting production

FAQ from MCP Test Client

What is MCP Test Client used for?

It is used to test MCP servers during development by acting as a bridge between Claude and the server under test.

How do I install the MCP Test Client?

Run npm install to install dependencies and npm run build to compile the TypeScript project.

How do I register the MCP Test Client with Claude?

The server is registered with Claude via the claude-mcp-local script (details are in the project’s usage instructions).

What transport does MCP Test Client use?

It implements a custom transport for stdio communication with the servers being tested.

What are the main tools provided by MCP Test Client?

The tools include mcp_test_deploy_server, mcp_test_call_tool, mcp_test_run_tests, mcp_test_get_logs, mcp_test_list_servers, and mcp_test_stop_server.