MCP Test Client

Source

An MCP Server that's also an MCP Client. Useful for letting Claude develop and test MCPs without needing to reset the application.

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Overview

MCP Test Client is a middleware that acts as both a server and a client for testing MCP servers during development, allowing developers to test without needing to register servers directly with Claude.

To use the MCP Test Client, install the dependencies, build the project, and then deploy servers or run tests using the provided CLI commands.

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

Testing new MCP server implementations
Debugging issues in server functionality
Running automated tests on deployed servers

Add to your AI client

Use these steps to connect MCP Test Client in Cursor, Claude, VS Code, and other MCP-compatible apps. The same JSON appears in the Use with menu above for one-click copy.

Cursor

Add this to your .cursor/mcp.json file in your project root, then restart Cursor.

.cursor/mcp.json

{
  "mcpServers": {
    "mcp-client-server-willccbb": {
      "command": "npx",
      "args": [
        "-y",
        "@modelcontextprotocol/server-mcp-client-server-willccbb"
      ]
    }
  }
}

Claude Desktop

Add this server entry to the mcpServers object in your Claude Desktop config, then restart the app.

~/Library/Application Support/Claude/claude_desktop_config.json (macOS) or %APPDATA%\Claude\claude_desktop_config.json (Windows)

{
  "mcpServers": {
    "mcp-client-server-willccbb": {
      "command": "npx",
      "args": [
        "-y",
        "@modelcontextprotocol/server-mcp-client-server-willccbb"
      ]
    }
  }
}

Claude Code

Add this to your project's .mcp.json file. Claude Code will detect it automatically.

.mcp.json (project root)

{
  "mcpServers": {
    "mcp-client-server-willccbb": {
      "command": "npx",
      "args": [
        "-y",
        "@modelcontextprotocol/server-mcp-client-server-willccbb"
      ]
    }
  }
}

VS Code (Copilot)

Add this to your .vscode/mcp.json file. Requires the GitHub Copilot extension with MCP support enabled.

.vscode/mcp.json

{
  "servers": {
    "mcp-client-server-willccbb": {
      "type": "stdio",
      "command": "npx",
      "args": [
        "-y",
        "@modelcontextprotocol/server-mcp-client-server-willccbb"
      ]
    }
  }
}

Windsurf

Add this to your Windsurf MCP config file, then restart Windsurf.

~/.codeium/windsurf/mcp_config.json

{
  "mcpServers": {
    "mcp-client-server-willccbb": {
      "command": "npx",
      "args": [
        "-y",
        "@modelcontextprotocol/server-mcp-client-server-willccbb"
      ]
    }
  }
}

Cline

Open Cline settings, navigate to MCP Servers, and add this server configuration.

Cline MCP Settings (via UI)

{
  "mcpServers": {
    "mcp-client-server-willccbb": {
      "command": "npx",
      "args": [
        "-y",
        "@modelcontextprotocol/server-mcp-client-server-willccbb"
      ]
    }
  }
}

FAQ

Can I test multiple servers at once?

Yes! You can deploy and test multiple servers using the CLI interface.

Is there a graphical interface for testing?

Currently, the MCP Test Client provides a CLI interface, but future enhancements may include a GUI.

How do I report issues or contribute?

You can report issues or contribute by visiting the project's GitHub repository.

Developer tools