Email API for Developers

Give your AI agents a production-ready inbox. Send, receive, and thread email programmatically — dedicated identity, real-time delivery, managed deliverability.

Why existing email APIs fall short for agents

SendGrid / Postmark

Built for outbound transactional email only. No receiving, no threading, no identity. Your agent can send a receipt but can't hold a conversation.

Google Workspace

$7–22/month per inbox, not built for programmatic use. New accounts land in spam fast without warmup, and there's no structured inbound event API.

Roll your own

Postfix + DKIM + SPF + ingestion pipeline + attachment parsing + bounce management. Weeks of work before your agent sends a single email — and ongoing maintenance that has nothing to do with what your agent is supposed to do.

What the OpenMail API gives you

Inbox provisioning

One API call creates a live inbox on your domain and returns the address immediately. No manual DNS steps, no waiting.

Send

Full SMTP-backed sending with pre-warmed reputation. Under 2 seconds at p95. Your agent's emails reach the primary inbox.

Receive

Inbound emails delivered as structured JSON via webhook or WebSocket in under 500ms. No polling, no ingestion pipeline to build.

Thread history

Full conversation context available as structured JSON via the history endpoint. Feed it directly into your agent's context window.

Attachment parsing

PDF, CSV, and DOCX files automatically extracted to plain text. Your agent gets the content of a document without handling MIME types.

Deliverability

SPF, DKIM, and DMARC configured automatically on provisioning. Continuous reputation monitoring. Primary inbox from day one.

Up and running in two commands

npm install -g @openmail/cli
openmail setup

One inbox, one domain, live in under a minute. Scale to thousands programmatically.

What developers are building with it

Personal AI assistants

Branded inboxes for AI assistants that manage schedules, draft replies, and communicate on behalf of clients from a real address.

Autonomous support agents

Agents that receive tickets, read full thread history, draft a response, and send it — no human in the loop, no separate ticketing system required.

Ops agents

Agents that sit on invoices@company.com, receive vendor emails, parse PDF attachments into structured data, and extract line items automatically.

Sales agents

Outbound sequences sent from a real domain with pre-warmed reputation. Replies land in the agent's inbox in full thread context.

Browser agents

Agents that complete signup flows autonomously — entering an email, receiving OTP codes and verification links, confirming accounts without human involvement.

Frequently asked questions

Every AI agent deserves its own inbox.