Webhook Notifications

Integration Guide

Payload Format

Every webhook delivery sends a JSON POST request:

{
  "event": "monitor_alert",
  "timestamp": "2026-05-11T14:32:00Z",
  "data": {
    "monitor_id": "mon_abc123",
    "url": "https://example.com/terms",
    "previous_score": 82,
    "current_score": 61,
    "threshold": 70,
    "changes_detected": true
  }
}

Verifying HMAC Signatures

Each request includes an X-Frisby-Signature header containing an HMAC-SHA256 hex digest of the raw body, signed with your webhook secret:

const crypto = require('crypto');
const sig = req.headers['x-frisby-signature'];
const expected = crypto
  .createHmac('sha256', YOUR_WEBHOOK_SECRET)
  .update(rawBody)
  .digest('hex');
if (sig !== expected) return res.status(401).end();

Retry Policy

• Frisby retries failed deliveries (non-2xx responses) up to 3 times.
• Retry intervals: 1 minute, 5 minutes, 30 minutes.
• After 3 consecutive failures, the webhook is automatically paused. Re-enable it from this page.