Send Letters via MCP

Letter IRL is an MCP server that lets you send real, physical letters from any AI assistant that supports the Model Context Protocol.

How It Works

🔐

OAuth Authentication

Secure login via browser - no tokens to manage

🎫

Token Authentication

Personal Access Tokens for clients without OAuth support

💰

Same Pricing

Identical letter pricing as ChatGPT - no separate fees

Quick Start Guide

1

Create a Letter IRL Account

Sign up for Letter IRL to buy Letter Packs for sending. You'll use the same account to authenticate from your MCP client.

Sign Up / Sign In
2

Add MCP Server Configuration

Add the Letter IRL server to your MCP client's configuration file. The location varies by client—check your client's documentation.

Windows configuration:

{
  "mcpServers": {
    "letter-irl": {
      "command": "npx.cmd",
      "args": [
        "-y",
        "mcp-remote",
        "https://api.letterirl.com/mcp"
      ]
    }
  }
}

macOS / Linux configuration:

{
  "mcpServers": {
    "letter-irl": {
      "command": "npx",
      "args": [
        "-y",
        "mcp-remote",
        "https://api.letterirl.com/mcp"
      ]
    }
  }
}
3

Restart & Authenticate

Fully restart your MCP client (check the system tray on Windows). On first use, a browser window will open asking you to log in to Letter IRL. Complete the authentication to connect.

💡Look for the MCP server indicator (hammer icon) in the bottom-right of the chat input. This confirms the connection is active.
4

Start Sending Letters!

You're all set. Try asking your AI assistant to send a letter:

"Send a thank you letter to John at 123 Main St, New York, NY 10001"
Other MCP Clients (API Token)

For MCP clients that don't support OAuth authentication, you can use a Personal Access Token instead. Generate a token in your dashboard and include it in your configuration.

Manage API Tokens

Pricing

Same letter pricing as ChatGPT. No separate pricing for MCP usage.

View Letter Packs

Troubleshooting

OAuth login window doesn't appear?

Check that your browser isn't blocking pop-ups. Try fully restarting your MCP client (check the system tray on Windows).

'Invalid authorization code' error?

Clear the auth cache and restart. On Windows: Remove-Item -Recurse -Force "$env:USERPROFILE\.mcp-auth" in PowerShell. On macOS/Linux: rm -rf ~/.mcp-auth

Windows path errors ('C:\Program' not recognized)?

Make sure you're using "npx.cmd" (not "npx") in your config on Windows.

Configuration errors?

Ensure the JSON is valid (no trailing commas). Verify the config file path for your OS.

Connection issues?

Check your internet connection. The MCP server is at api.letterirl.com

Ready to Get Started?

Create an account and start sending letters from your MCP client in minutes.

Sign Up / Sign InBuy Letters