Mail real letters from your AI agent

Ask Claude , ChatGPT , Cursor or Meta Muse to "mail this letter to Jane Doe in Austin". Your agent checks the address with USPS, shows you a preview, and mails the letter by USPS First-Class once you say yes.

Get API Access Connect Your Agent

Server URL

https://mcp.sprintmail.io/mcp
  1. letter.pdf 2 pages

    Mail this to Jane Doe, 123 Main St, Austin TX 78701.

  2. Used Sprint Mail check_addresses

    The address checks out with USPS. Here is the preview. Nothing is sent yet.

    Letter preview
    Not sent yet
    To
    Jane Doe, Austin, TX 78701
    Letter
    2 pages, black and white
    Mail
    USPS First-Class

    Want me to mail it?

  3. Yes, mail it.

    Read

  4. Used Sprint Mail send_letters

    Done. Order ord_8f2k1c is on its way to print. Track it at tracking.sprintmail.io.

Message your agent

Built to be safe

Every send starts as a preview you can read.

  • A preview before every send.

    The server answers every send with a preview first and asks your agent to wait for your yes.

  • What you saw is what goes out.

    The preview is locked to those exact letters for 15 minutes. Change a recipient and it has to preview again. Retrying the same order never mails it twice.

  • Your key stays yours.

    The server stores nothing; each request carries your own API key.

  • Staging first.

    New partners start with a staging key. Staging orders never print, and our team can move one to production for you.

Connect your agent

MCP Server Reference

  • Claude

    Settings, then Connectors, then Add custom connector. Paste the server URL.

  • Claude Code

    Run this in your terminal:

    claude mcp add --transport http sprintmail https://mcp.sprintmail.io/mcp --header "Authorization: Bearer YOUR_KEY"

  • ChatGPT

    Settings, then Apps and Connectors, then add the server URL in developer mode.

  • Cursor, Claude Desktop

    Add the local server with SPRINTMAIL_API_KEY set:

    npx -y @sprintmail/mcp

  • Meta Muse

    Ask Muse: "Connect to the Sprint Mail MCP server at https://mcp.sprintmail.io/mcp over streamable HTTP, with my API key as a Bearer header."

Ready to mail real letters?

Get API Access

What it can do

The MCP server runs on the same API your developers can call directly.

About the Print and Mail API
  • Check up to 50 addresses with USPS
  • Price letters by page count
  • Mail PDF letters, one or many, as one order
  • Mail a saved template to a new recipient
  • List your orders and each letter's status, with tracking links

Questions

The short answers. Anything else, ask in your application and we reply within 2 business days.

Which AI agents and assistants work?

Any that supports MCP over streamable HTTP or a local command: Claude, ChatGPT, Cursor, Claude Code, Meta Muse and more.

How do I try it?

Become a partner. Approved partners start with a staging key on mcp.sprintmail.io/staging/mcp: every tool works and nothing prints. Our team can move a staging order to production for you. Then you get a production key.

Will the agent mail something without asking me?

The server answers every send with a preview and asks the agent to wait for your yes, and most agents also ask before they run a tool that sends. The preview is locked to those exact letters, so what goes out is what you saw.

Test on staging, then mail for real

Approved partners start with a staging key and move to production when they are ready. Tell us what you mail.

Get API Access