MailStream is a Model Context Protocol (MCP) server: The first MCP server for physical mail: send postcards and letters, manage lists and campaigns. As an MCP server it plugs straight into AI assistants, exposing its functionality as tools the model can invoke on your behalf.
It's a hosted (remote) server — point your client at https://my.mailstream.app/mcp and you're connected, with nothing to install locally. The current release is v1.0.0.
You'll find MailStream in the Marketing category here on mcp.site; it connects to Claude Desktop, Claude Code, Cursor, VS Code, Windsurf, Zed, and any other MCP client — see the install snippets below. If you maintain MailStream for mailstream.app, claim this listing to verify ownership, earn the Verified badge, and keep the details current.