Creating Monitors

Monitors are the core resource in DiffHook. Each monitor watches one URL and fires events when content changes.

Required fields

Field	Type	Description
url	string	The URL to monitor
webhookUrl	string	Where to send change events
intervalMinutes	integer	How often to check

Valid intervals: 5, 15, 30, 60, 360, 1440 (minutes).

Optional fields

label — A human-readable name shown in the dashboard. Defaults to the URL.

cssSelector — Scope the diff to a specific DOM element. Reduces noise from nav bars, cookie banners, and other boilerplate.

{
  "cssSelector": "#pricing-table"
}

jsRendering — Use a headless Chromium browser to render the page before taking a snapshot. Required for React/Vue/Angular apps that render content client-side. Slower and costs 3× credits.

Example: monitoring a pricing page

curl -X POST https://www.diffhook.com/api/monitors \
  -H "Authorization: Bearer dh_live_yourkey" \
  -H "Content-Type: application/json" \
  -d '{
    "url": "https://competitor.com/pricing",
    "webhookUrl": "https://n8n.example.com/webhook/abc",
    "intervalMinutes": 60,
    "label": "Competitor pricing",
    "cssSelector": "#pricing-table"
  }'

Example: monitoring an RSS feed

RSS feeds are plain XML, so no JS rendering needed. Short intervals work well:

curl -X POST https://www.diffhook.com/api/monitors \
  -H "Authorization: Bearer dh_live_yourkey" \
  -H "Content-Type: application/json" \
  -d '{
    "url": "https://sec.gov/cgi-bin/browse-edgar?action=getcompany&company=acme",
    "webhookUrl": "https://hooks.zapier.com/hooks/catch/abc",
    "intervalMinutes": 15,
    "label": "SEC EDGAR filings"
  }'

Updating a monitor

You can update any mutable field with a PUT request. Only provided fields change:

curl -X PUT https://www.diffhook.com/api/monitors/mon_abc123 \
  -H "Authorization: Bearer dh_live_yourkey" \
  -H "Content-Type: application/json" \
  -d '{
    "intervalMinutes": 360,
    "webhookUrl": "https://new-endpoint.example.com/hook"
  }'

Pausing and resuming

Pausing a monitor stops polling and credit consumption. Useful for maintenance windows:

# Pause
curl -X POST https://www.diffhook.com/api/monitors/mon_abc123/pause \
  -H "Authorization: Bearer dh_live_yourkey"

# Resume
curl -X POST https://www.diffhook.com/api/monitors/mon_abc123/resume \
  -H "Authorization: Bearer dh_live_yourkey"