Every email event, pushed to you

Replies, inbound mail, deliveries and bounces arrive at your endpoint as they happen: signed, retried, and replayable.

Events

React to email
the moment it moves

Pick the events you want. Each one arrives as JSON, with the same envelope the API and the event stream use.

{
  "id": "evt_01K…",
  "type": "reply.received",
  "created_at": "2026-10-05T10:42:07.000Z",
  "agent_id": "agt_01K…",
  "thread_id": "thrd_01K…",
  "injection_score": 0.02,
  "sender_reputation": 0.85,
  "data": {
    "from": { "address": "dana@example.com", "name": "Dana" },
    "subject": "Re: Your October invoice",
    "extracted_text": "Paid it this morning, thanks!"
  }
}

Dashboard

See every event
as it happens

The Events page streams every send, delivery, reply and bounce live, with the scores each inbound message carried.

The Events page of the dashboard: a live list of events, each with its status, the message it is about and its time

We check the signature and dedupe on the event id. Retries cover the rest.

Imani BrooksBackend Engineer at Tinderbeak

Webhook docs

Delivery

Built to outlast
a bad deploy

Every delivery is signed with HMAC-SHA256 in one X-Mails-Signature header, so your handler can check it came from us. Rotate the secret and the old one signs beside it for 24 hours.

Retried for you
If your endpoint is down or answers with an error, we try again after 30 seconds, then after 2 more minutes. Any 2xx answer counts as delivered.
Learn more
Replays on demand
A delivery that fails all three attempts is kept, not dropped. Replay it from the dashboard or the API once your handler is fixed.
Learn more

Set up

From endpoint
to first event

Two steps from an endpoint to events in your app.

Step 1
Add your endpoint
Add an HTTPS address and the events you want. You get a signing secret back.

Step 2

Check it, then act

Check the signature against your secret, then act. Answer with any 2xx.

// verify(): the helper in /docs/webhooks
import { verify } from "./verify";

export async function POST(req: Request) {
  const { headers } = req;
  const body = await req.text();
  const ok = verify(
    body,
    headers.get("x-mails-signature") ?? "",
    process.env.MAILS_WEBHOOK_SECRET!,
  );
  if (!ok) {
    return new Response("Bad signature", {
      status: 400,
    });
  }

  const event = JSON.parse(body);
  // act on event.type
  return new Response();
}

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Every email event, pushed to you

React to email the moment it moves

See every event as it happens

Built to outlast a bad deploy

Retried for you

Replays on demand

From endpoint to first event