The action layer for AI agents.
AI agents can reason, plan, and write. What they cannot do is act in the real world, because almost every service on the internet gates access behind an email address, a verification code, and a login. Lumbox is the layer that gives an agent those hands.
What we build
Lumbox is email infrastructure built specifically for autonomous software. One API call creates a real, agent-owned inbox. Every message that arrives is parsed automatically into clean JSON, with OTP codes, verification links, magic links, and backup codes extracted for you. A long-poll endpoint blocks until the code lands, so the agent never writes a polling loop.
Around that inbox we built the rest of the action layer: a stealth browser for signups and logins, an encrypted credential vault so an agent can hold its own passwords, custom domains with full DKIM, SPF, and DMARC, realtime webhooks, IMAP and SMTP access, and 73 MCP tools for Claude Code and Cursor. One platform, one key.
Who builds it
Lumbox is built by Deepanshu Kumar, an engineer who kept hitting the same wall while building agents: the agent was ready to act, but had no inbox of its own and no way to clear a verification step. Rather than rebuild a mail server for every project, he turned the missing piece into a product.
It is built in public. You can follow the work and reach the founder directly on X (@kumard_3) and GitHub. Support questions go straight to a human at support@lumbox.co.
How it runs
The API and mail server run on dedicated hardware in Germany (Hetzner). The database is hosted on Neon, and this site sits behind Cloudflare. Sensitive data is encrypted at rest with AES-256-GCM, and the credential vault uses envelope encryption with a separate key per organization, so we cannot read what you store. We do not sell your data, and we never use your email content to train AI models.
If you would rather own the whole stack, Lumbox is self-hostable and runs on a $5 server. Full detail on how we protect data lives on the security page.
A note on the name
Lumbox started life as AgentMailr. We rebranded in March 2026 after a trademark notice, but the product, API, and inboxes are unchanged. The full story is on the rebrand page.