I've been building AI agents for the past year, and I kept running into the same problem: my agent couldn't sign up for anything.

  It needed to create accounts, which means receiving verification
  codes. It needed to send reports. It needed to check inboxes. Every
  time, I'd hack something together. Resend for sending (but it can't
  receive). Gmail API with its OAuth setup that takes half an hour. Or
   just... doing it by hand.

  So I built mails-agent. The idea is simple. Give your agent a real
  email address, the same way you'd give it a tool or an API key.

    npm install -g mails-agent
    mails claim myagent
    mails code --to myagent@mails0.com --timeout 60

  That last command waits for a verification code to arrive and prints
   it. Your agent can now sign up for things on its own.

  I've spent years building products for people. This is the first
  time I'm building something for agents, and honestly it's the most
  fun I've had in a long time. It's a completely different mindset.
  You're not thinking about UI or attention spans. You're thinking
  about reliability, programmability, zero friction. Everything is an
  API call. It just needs to work.

  A couple of things I'm happy with:

  1. It runs entirely on Cloudflare's free tier (Workers + D1 + R2 +
  Email Routing). I wanted this to cost $0. Charging per mailbox felt
  wrong for something agents need as a basic capability.

  2. It works as an MCP server, so Claude Desktop and Cursor can use
  it directly: npx mails-agent-mcp

  MIT licensed. Self-hostable. Deploy to your own Cloudflare account
  with your own domain, or claim a free @mails0.com mailbox to try it.

  I'd love to hear what you'd use this for. I built it for the signup
  and verify use case, but I think there are agent email patterns I
  haven't thought of yet.

  Demo: https://mails0.com