Web Monitor
Track web pages for changes. Stores snapshots, computes diffs, supports CSS selectors.
Triggers
Activate this skill when the user wants to:
- Watch a website for content changes
- Track price changes, new posts, or updated content on a page
- Set up page change alerts or notifications
- Check if a site has been updated since last visit
- Monitor a specific section of a page (with CSS selector)
NOT For
- Real-time alerting on dynamic topics — use the
topic-monitorskill for news/topic monitoring with importance scoring - Full page archival — this tracks diffs, not full crawl archives
- JavaScript-heavy SPAs — the monitor fetches raw HTML; dynamic content rendered by JS may not be captured accurately
- Monitoring APIs or webhooks — use cron + exec for structured data endpoints
Quick Start
# Add a URL to watch
uv run --with beautifulsoup4 python scripts/monitor.py add "https://example.com" --name "Example"
# Add with CSS selector (monitor specific section)
uv run --with beautifulsoup4 python scripts/monitor.py add "https://example.com/pricing" -n "Pricing" -s ".pricing-table"
# Check all watched URLs for changes
uv run --with beautifulsoup4 python scripts/monitor.py check
# Check one specific URL
uv run --with beautifulsoup4 python scripts/monitor.py check "Example"
# List watched URLs
uv run --with beautifulsoup4 python scripts/monitor.py list
# View last diff
uv run --with beautifulsoup4 python scripts/monitor.py diff "Example"
# View current snapshot
uv run --with beautifulsoup4 python scripts/monitor.py snapshot "Example" --lines 50
# Remove
uv run --with beautifulsoup4 python scripts/monitor.py remove "Example"
Commands
| Command | Args | Description |
|---|---|---|
add | <url> [-n name] [-s selector] | Add URL to watch, take initial snapshot |
remove | <url-or-name> | Stop watching a URL |
list | [-f json] | List all watched URLs with stats |
check | [url-or-name] [-f json] | Check for changes (all or one) |
diff | <url-or-name> | Show last recorded diff |
snapshot | <url-or-name> [-l lines] | Show current snapshot |
Output Symbols
- 🔔 CHANGED — page content changed (shows diff preview)
- ✅ No changes
- 📸 Initial snapshot taken
- ❌ Error fetching
Data
Stored in ~/.web-monitor/ (override with WEB_MONITOR_DIR env var).
For OpenClaw workspace integration, set WEB_MONITOR_DIR=$WORKSPACE/data/web-monitor (where $WORKSPACE is your agent workspace path).
watches.json— watch list configsnapshots/— stored page content + diffs
Tips
- Use
--selectorto monitor specific elements (prices, article lists, etc.) - Use
--format jsonfor programmatic checking (heartbeat integration) - CSS selectors require beautifulsoup4 (included via
--withflag) - Text is normalized to reduce noise from timestamps, whitespace, ads