Other · Remote MCP server
3LT Letter Mail
Give AI assistants hands: send real USPS letters via MCP.
What the MCP Registry states
The entry as published to the official MCP Registry (read 2026-10-04), latest version.
- Registry name
com.3lgrouptechnology/3lt-letter-mail- Version
- 1.0.0
- Status
- Active
- Category
- other
- Transport
- Streamable HTTP
- Published
- 2026-10-03
- Updated
- 2026-10-03
- Publisher
- com.3lgrouptechnology
- Namespace
- Namespace verified by the MCP Registry via the domain 3lgrouptechnology.com · how
- Repository
- github.com/3LGroupTechnology/3lt-letter-mail
- Source
- Registry API entry
Remote endpoints
| Transport | URL | Headers declared |
|---|---|---|
| Streamable HTTP | https://3lgrouptechnology.com/mcp | None |
Live check
This directory connected to each remote endpoint and asked for its list of tools. The check connects and lists tools only; it doesn't run tools, sign in or test security.
- Reachable
- Yes (HTTP 200)
- Handshake
- 3l-group-technology-letter-mail 4.0.10 · protocol 2025-06-18
- Tools discovered
- 3:
draft_letter,request_send,send_status - Checked on
- 2026-10-05
How to connect 3LT Letter Mail
3LT Letter Mail is a remote MCP server: there is nothing to install. Its endpoint is https://3lgrouptechnology.com/mcp, served over Streamable HTTP. In an assistant that accepts remote MCP servers (often under a setting named connectors, integrations or tools), add a new server and give it this URL; in a client configured by file, add it as a remote (HTTP) server with the same URL.
No headers are declared in the registry entry. If the server needs you to sign in, a client that supports MCP authorization opens the service's own sign-in page when it first connects.
Derived from the registry entry; the live check above only shows whether the endpoint answered. What the server does, and on what terms, is set by its publisher; check its repository or website before giving it access to your accounts or files. How to add an MCP server to an assistant · Before you connect
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