MCP Test Servers

What it does

MCP Test Servers provides a comprehensive collection of MCP server implementations for testing and validating MCP client behavior. It includes interactive app servers (ui, graphing) that render inline UI components, along with dozens of test servers covering tools, resources, prompts, elicitation, OAuth flows, and protocol edge cases. Ideal for MCP client developers and integrators who need to verify their implementations against known test patterns.

Key features

• Interactive UI apps — ui server renders a button that calls the get-time tool and displays the result inline; graphing server renders Chart.js charts inline
• Elicitation testing — Dedicated server for testing MCP's structured form elicitation feature (name, age, contact, preferences)
• OAuth flow validation — Multiple OAuth test servers covering discovery, callbacks, and edge-case scenarios across different ports
• Protocol stress testing — Servers for broken tools, crash-on-startup, duplicate names, missing types, and malformed schemas to validate error handling
• Comprehensive feature coverage — everything server tests all MCP features: tools with/without params, resources, prompts, elicitation, dynamic tools, roots, and environment variables

Installation

Cursor:

{
  "mcpServers": {
    "mcp-test-servers": {
      "command": "npx",
      "args": ["-y", "@msfeldstein/mcp-test-servers", "ui"]
    }
  }
}

Claude Desktop:

{
  "mcpServers": {
    "mcp-test-servers": {
      "command": "npx",
      "args": ["-y", "@msfeldstein/mcp-test-servers", "everything"]
    }
  }
}

VS Code Copilot:

{
  "servers": {
    "mcp-test-servers": {
      "type": "stdio",
      "command": "npx",
      "args": ["-y", "@msfeldstein/mcp-test-servers", "ui"]
    }
  }
}

Supported hosts

Cursor, Claude Desktop, VS Code Copilot