AI agents

Give your AI agents a real mailbox

Let agents send and receive email over a clean, predictable HTTP API — ideal for automated workflows, tool use, and human-in-the-loop email.

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Programmable mailbox

Agents read, send, and reply to email like any other tool call.

Machine-readable discovery

OpenAPI 3.1, interactive docs, llms.txt, and an installable agent skill ship with every deployment.

Per-agent keys

Give each agent a personal key narrowed to a domain or selected mailboxes.

Send, read, reply

Full inbound + outbound, so agents can hold real conversations.

example.ts

// Receive, then let your agent reply — all over plain HTTP.
const MARKRELAY_API_URL = process.env.MARKRELAY_API_URL; // https://mail.yourdomain.com/openapi/v1
const MARKRELAY_API_KEY = process.env.MARKRELAY_API_KEY;

const inbox = await fetch(
  `${MARKRELAY_API_URL}/emails?mailbox=agent@yourdomain.com&folder=inbox&read=false`,
  { headers: { Authorization: `Bearer ${MARKRELAY_API_KEY}` } },
).then((r) => r.json());

await fetch(`${MARKRELAY_API_URL}/emails/${inbox.items[0].id}/reply`, {
  method: "POST",
  headers: { Authorization: `Bearer ${MARKRELAY_API_KEY}`, "Content-Type": "application/json" },
  body: JSON.stringify({ text: agentReply }),
});

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Multi-Domain Mailboxes

Own your email stack today

Buy MarkRelay once and run it in your Cloudflare account. MarkRelay adds no per-message or per-seat charge; Cloudflare usage and service limits remain separate.

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