Tracks web pages for changes, downtime, or content removal using services like Visualping, Distill.io, and ChangeTower, plus self-hosted options like changedetection.io. You'd reach for this when monitoring competitor pricing, watching for job postings, preserving content before it gets deleted, or generating alerts when pages go dark. The comparison table is genuinely useful since free tiers keep shrinking (Visualping tightened theirs, UptimeRobot dropped free SMS). The Python examples cover both element-level monitoring with CSS selectors and basic uptime checks via UptimeRobot's API. Self-hosted tools win on privacy and control, but managed services save you from running cron jobs if you just need a handful of monitors.
npx skills add https://github.com/jamditis/claude-skills-journalism --skill page-monitoring