"for": ["tests", "agents"]

Mail in.{JSON} out.

Programmable inboxes for your tests and your agents. Create any address on the fly, wait for the email, get the code or link back as JSON. For CI pipelines and AI agents.

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From: Acme <[email protected]>

To: [email protected]

Subject: Your Acme code

Content-Type: text/plain

Hi there,

Use 847291 to verify your email,

or open acme.com/verify?t=9c1e…

Thanks,

The Acme team

email.received

{

"email": {

"subject": "Your Acme code",

"links": ["https://acme.com/verify?t=9c1e…"]

"otp": { "code": "847291", "source": "body" }

}

{"to":"signup-01-[email protected]","code":"847291"}{"to":"reset-42-[email protected]","link":"/reset?t=9c1e…"}{"to":"agent-task-118-[email protected]","code":"306142"}{"to":"invite-qa-[email protected]","link":"/accept?i=7Hq2…"}{"to":"login-run-2291-[email protected]","code":"552018"}{"to":"magic-link-07-[email protected]","link":"/auth?m=Kd83…"}{"to":"otp-ci-5531-[email protected]","code":"719904"}{"to":"signup-01-[email protected]","code":"847291"}{"to":"reset-42-[email protected]","link":"/reset?t=9c1e…"}{"to":"agent-task-118-[email protected]","code":"306142"}{"to":"invite-qa-[email protected]","link":"/accept?i=7Hq2…"}{"to":"login-run-2291-[email protected]","code":"552018"}{"to":"magic-link-07-[email protected]","link":"/auth?m=Kd83…"}{"to":"otp-ci-5531-[email protected]","code":"719904"}

"how": [

An inbox of its own, in three calls.

01
Add the MCP server
One command in Claude Code, or a few lines of JSON in any MCP client. Your project API key is the only setting.
02
The agent calls create_inbox
It gets a fresh address of its own, plus the timestamp to wait from, and types the address into the sign-up form.
03
It waits for the code
wait_for_email holds until the message lands and returns the code and links as JSON. No inbox scraping, no regex.

acme.com/signup

Create your account

[email protected]

We’ll email you a 6-digit code

Verification code

6-digit code

Create accountVerifying emailAccount verified

Agent

create_inboxreceiver

[email protected]

wait_for_emailreceiver

847291

claude mcp add receiver \
  -e RECEIVER_API_KEY=recv_live_... \
  -- npx -y @receiverdotemail/mcp

]

"answers": [

Three types of answer, all typed.

Ask for what you need and get it back as JSON, already extracted. No HTML scraping, no regex.

"code": "847291"

The code

Four, six or eight digits, found in the subject or the body, and we tell you which.

"links": ["https://…"]

The links

Magic links, resets and confirmations, pulled out of every message, ready to open.

"email": { subject, text }

The message

Sender, subject and body as text or HTML, with attachments when you need them.

]

"features": {

Everything an inbox needs to be programmable.

No SMTP server, no DNS, no mailbox to log in to. Mail lands, gets parsed, and waits for you as JSON.

Signed webhooks. Every email posted to your endpoint as email.received, signed and retried.

POSTci.northwind.dev/hooks/mail Delivering

HMAC-SHA256 verified84 ms · attempt 1 of 3

Mail usually lands within2sLong-polling returns the moment it arrives, so tests wait for mail instead of sleeping.

Unlimited addresses. Every prefix under your suffix is an inbox. Nothing to register first.

"reset-42"

Isolated projects. Each with its own addresses, mail and API keys. One per test suite, agent or team.

Checkout suite"*[email protected]"recv_live_k7m2…

Four ways in. REST API, TypeScript and Python SDKs, an MCP server for agents and a CLI. Same answers from each.

RESTGET /emails/waitTSwaitForOtp()MCPcreate_inboxCLIreceiver otpPYwait_for_otp()RESTPOST /inboxes

MCPwait_for_emailPYpip install receiverdotemailCLIreceiver watchRESTGET /emails/streamTSinboxes.create()

CLIreceiver inbox newTSnpm i @receiverdotemail/sdkMCPget_emailRESTGET /emails/otpPYemails.wait_for()

}

"readers": [

One inbox, two kinds of reader.

The same inboxes serve a test suite in CI and an agent working on its own.

"tests"

End-to-end tests

Sign-up, password reset, magic links and receipts, asserted in CI. A fresh address per test means parallel runs never read each other’s mail.

✓TypeScript and Python SDKs
✓waitForOtp() instead of sleep()
✓Works in any CI

Testing with Receiver "agents"

AI agents

Agents that sign up for tools, verify accounts or read a confirmation get an inbox of their own through MCP, with the code handed back as JSON.

✓MCP server with four tools
✓One API key, no OAuth
✓CLI for scripted agents

Agents with Receiver

Also used for shared team inboxes to check flows by hand, and monitoring production email.

"stack": [

Drop it into the tests you already have.

More in the guides: CI/CD, Jest / Vitest, Pytest and agents.

password-reset.test.tsJest / Vitest

1import { ReceiverClient } from "@receiverdotemail/sdk";2 3const receiver = new ReceiverClient({4  apiKey: process.env.RECEIVER_API_KEY,5});6 7it("sends a reset email with a working link", async () => {8  const inbox = await receiver.inboxes.create({ prefix: "reset" });9  await app.requestPasswordReset(inbox.address);10 11  const email = await receiver.emails.waitFor({12    recipient: inbox.address,13    since: inbox.createdAt,14    timeout: 30,15  });16 17  expect(email.subject).toContain("Reset");18  expect(email.links.some((l) => l.includes("/reset"))).toBe(true);19});

test_login.pyPytest

1import os, pytest2from receiverdotemail import ReceiverClient3 4@pytest.fixture5async def receiver():6    async with ReceiverClient(7        api_key=os.environ["RECEIVER_API_KEY"]8    ) as client:9        yield client10 11async def test_login_code(receiver, app):12    inbox = await receiver.inboxes.create(prefix="login")13    await app.send_login_code(inbox.address)14 15    otp = await receiver.emails.wait_for_otp(16        recipient=inbox.address,17        since=inbox.created_at,18        timeout=30,19    )20    assert len(otp.code) == 6