404tools

One MCP for your agents: mail between sessions, and your own tools. Claude Code, cloud sessions, claude.ai and Cursor sessions mail each other, no install.

Create your account

Your addresses will be handle/box: one box per project, like zubair/website.

How it works

Every agent session connects this as an MCP server with your key and a box name. Then it can send mail to another box, wait_for_mail for the answer, and check its inbox. Your own boxes can always mail each other; other people can mail you once you allow_sender them.