Calc MCP

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Installation ​

Calc MCP works with any MCP-compatible client. Below are setup guides for popular AI assistants.

Claude Code ​

The fastest way to add Calc MCP to Claude Code:

bash
claude mcp add -s user calc-mcp -- npx --prefix /tmp -y @coo-quack/calc-mcp@latest

This adds the server to your user-level MCP configuration.

To verify it's working:

bash
claude mcp list

You should see calc-mcp in the list.

Claude Desktop ​

Add to your Claude Desktop config file:

macOS:

bash
~/Library/Application Support/Claude/claude_desktop_config.json

Windows:

bash
%APPDATA%\Claude\claude_desktop_config.json

Config:

json
{
  "mcpServers": {
    "calc-mcp": {
      "command": "npx",
      "args": ["--prefix", "/tmp", "-y", "@coo-quack/calc-mcp@latest"]
    }
  }
}

After editing, restart Claude Desktop. You should see "MCP" in the bottom-right corner with the 21 tools available.

Cursor ​

Add to ~/.cursor/mcp.json:

json
{
  "mcpServers": {
    "calc-mcp": {
      "command": "npx",
      "args": ["--prefix", "/tmp", "-y", "@coo-quack/calc-mcp@latest"]
    }
  }
}

Restart Cursor after adding the config.

Windsurf ​

Add to ~/.codeium/windsurf/mcp_config.json:

json
{
  "mcpServers": {
    "calc-mcp": {
      "command": "npx",
      "args": ["--prefix", "/tmp", "-y", "@coo-quack/calc-mcp@latest"]
    }
  }
}

Restart Windsurf after adding the config.

VS Code (GitHub Copilot) ​

For workspace-specific setup, add .vscode/mcp.json in your project:

json
{
  "servers": {
    "calc-mcp": {
      "command": "npx",
      "args": ["--prefix", "/tmp", "-y", "@coo-quack/calc-mcp@latest"]
    }
  }
}

Reload VS Code after creating the file.

Other MCP Clients ​

Calc MCP works with any MCP-compatible client that supports stdio transport. To integrate with a client not listed above, configure it to run:

bash
npx --prefix /tmp -y @coo-quack/calc-mcp@latest

The server communicates over stdio using the standard Model Context Protocol. Most clients accept a command + args configuration similar to the examples above.

Direct Usage ​

You can also run the server directly for testing:

bash
npx --prefix /tmp -y @coo-quack/calc-mcp@latest

Or install globally:

bash
npm install -g @coo-quack/calc-mcp@latest
calc-mcp

Troubleshooting ​

"npx: command not found" ​

Make sure Node.js (v18+) is installed:

bash
node --version
npm --version

Install from nodejs.org if needed.

Tools not showing up ​

  1. Restart the app after editing the config file
  2. Check the config path — make sure you edited the right file
  3. Validate JSON — use a JSON validator to check for syntax errors
  4. Check logs — Claude Desktop and other apps may have logs showing connection errors

"calc-mcp: command not found" inside a Node.js project ​

If you run npx inside a directory that contains node_modules, npx may fail with:

sh: calc-mcp: command not found

This happens because npx resolves the scoped package locally but fails to link the binary correctly. All the examples on this page already include the fix (--prefix /tmp), which forces npx to use a separate directory for package resolution:

bash
npx --prefix /tmp -y @coo-quack/calc-mcp@latest

Version info ​

To check the installed version:

bash
npx --prefix /tmp @coo-quack/calc-mcp@latest --version

Next Steps ​

Released under the MIT License.

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