MCP Failure Lab

Claude Code

1. Run this in a terminal, in your project folder:

claude mcp add --transport stdio mcp-failure-lab -- npx -y mcp-failure-lab

2. Start Claude Code and type /mcp. mcp-failure-lab should show as connected.

Add --scope user to make it available in every project.

Claude Desktop

1. Open Settings → Developer → Edit Config. It opens claude_desktop_config.json. Add:

{
  "mcpServers": {
    "mcp-failure-lab": {
      "command": "npx",
      "args": [
        "-y",
        "mcp-failure-lab"
      ]
    }
  }
}

2. Save the file and restart Claude Desktop.

Needs Node.js on your computer. The file lives in ~/Library/Application Support/Claude/ on macOS and %APPDATA%\Claude\ on Windows.

Cursor

Add to Cursor (opens in a new tab)

Or add it by hand to ~/.cursor/mcp.json (all projects) or .cursor/mcp.json (this project):

{
  "mcpServers": {
    "mcp-failure-lab": {
      "command": "npx",
      "args": [
        "-y",
        "mcp-failure-lab"
      ]
    }
  }
}

Needs Node.js on your computer.

VS Code

Install in VS Code (opens in a new tab)

Or from a terminal:

code --add-mcp '{"name":"mcp-failure-lab","type":"stdio","command":"npx","args":["-y","mcp-failure-lab"]}'

Or commit it to the repo in .vscode/mcp.json:

{
  "servers": {
    "mcp-failure-lab": {
      "type": "stdio",
      "command": "npx",
      "args": [
        "-y",
        "mcp-failure-lab"
      ]
    }
  }
}

Needs Node.js on your computer.

Devin Desktop

1. Add it to ~/.config/devin/mcp_config.json (macOS and Linux) or %APPDATA%\devin\mcp_config.json (Windows):

{
  "mcpServers": {
    "mcp-failure-lab": {
      "command": "npx",
      "args": [
        "-y",
        "mcp-failure-lab"
      ]
    }
  }
}

2. Refresh the MCP server list in Cascade.

Devin Desktop is the new name for Windsurf.

Codex

codex mcp add mcp-failure-lab -- npx -y mcp-failure-lab

Or edit ~/.codex/config.toml directly:

[mcp_servers.mcp-failure-lab]
command = "npx"
args = ["-y", "mcp-failure-lab"]

Needs Node.js on your computer.

Gemini CLI

gemini mcp add mcp-failure-lab npx -- -y mcp-failure-lab

This adds it to the current project. Add -s user to use it everywhere.

Any client

Most clients that start local servers accept this shape:

{
  "mcpServers": {
    "mcp-failure-lab": {
      "command": "npx",
      "args": [
        "-y",
        "mcp-failure-lab"
      ]
    }
  }
}

Zed puts servers under context_servers in its settings, with the same command, args and env fields.

Needs Node.js on your computer.

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Website card

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iframe

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JSON

The listing as data for your own pages and tools: name, tagline, install command, tools and the “Add to” links. Any site can read it (CORS is open).

https://mcp.tc/i/mcp-failure-lab.json

What each field means