Send Simrix Monitor alerts to Microsoft Teams

Steps

1. In Teams, add an incoming webhook connector to the channel and copy its URL.
2. Create a relay that can receive a webhook and call that URL.
3. In Simrix Monitor, open Account → Webhooks, choose Add webhook, and paste the relay's URL.
4. Pick the events and save, copying the signing secret before you leave the page.
5. In the relay, verify the signature, then POST a card to the Teams connector with the monitor name, what failed and a link to the check.

Why does this need a relay?

A Teams connector expects a card format. Simrix Monitor sends its own JSON envelope with event, timestamp, workspaceId, monitor and run, which a connector will not render.

Since each delivery is attempted once with no retry, a rejected request is a lost alert rather than a delayed one. The relay's job is to turn one shape into the other.

What does Simrix Monitor send?

A single JSON POST per event. Here is a real body for a failed check.

{
  "event": "monitor_failed",
  "timestamp": "2026-09-14T14:03:11.482Z",
  "workspaceId": "clz9a1b2c3d4e5f6g7h8i9j0",
  "monitor": {
    "id": "clz8m0n1o2p3q4r5s6t7u8v9",
    "name": "Checkout smoke test",
    "type": "page_check",
    "url": "https://shop.example.com/checkout"
  },
  "run": {
    "id": "clz7r0u1n2i3d4e5f6g7h8i9",
    "status": "failed",
    "changeDetected": false,
    "aiSummary": "We could not find “#place-order” on the page at step 3 of 6. It may have been renamed or moved, or the page may not have got that far.",
    "failureSummary": "We could not find “#place-order” on the page at step 3 of 6. It may have been renamed or moved, or the page may not have got that far.",
    "failureReasonCode": "element_not_found",
    "durationMs": 31204,
    "httpStatus": 200,
    "screenshotUrl": "/api/artifacts/clz7r0u1n2i3d4e5f6g7h8i9/screenshot.png",
    "diffScreenshotUrl": null,
    "shareUrl": "https://simrixmonitor.com/r/Zq8nT2xK9pLm4vR7wYbC1dF3hJ5kN6sQ8tU0xW2yA4E"
  }
}

Which events can fire?

What is in the body?

Which headers arrive?

How do you verify the signature?

The signature is an HMAC-SHA256 of the raw request body, keyed with your signing secret and written as lowercase hex behind a sha256= prefix.

import crypto from "node:crypto";

// Sign the RAW body. Re-serialising parsed JSON will not match.
function isFromSimrixMonitor(rawBody, header, secret) {
  const expected =
    "sha256=" + crypto.createHmac("sha256", secret).update(rawBody).digest("hex");
  const a = Buffer.from(expected);
  const b = Buffer.from(header ?? "");
  return a.length === b.length && crypto.timingSafeEqual(a, b);
}

What should your receiver expect?

• Delivery is attempted once. A non-2xx response, a connection error or a timeout is logged and dropped. There is no retry, no backoff and no dead-letter queue, so treat a missed delivery as possible and reconcile from the app when it matters.
• The timeout is 10 seconds for the whole request. Acknowledge quickly and do your own work afterwards, rather than processing before you respond.
• The signature covers the raw body only. No timestamp is included, so there is no replay protection built in. If that matters, record run.id and ignore ids you have already handled.
• Change monitors only fire change_detected. A change monitor that errors does not send monitor_failed, and change monitors never send monitor_recovered. Subscribing to monitor_failed will not tell you a change monitor is broken.
• Failure and recovery webhooks follow the email toggles. Turning off Failure alerts or Recovery alerts on the notifications page turns off the matching webhook as well.
• Only scheduled checks send anything. Running a check by hand to try something out fires no webhook and sends no email.