// bot reference

VitalSentinel Bots

Information about our monitoring bots, how to identify them, and what they do when visiting your website.

Why am I seeing VitalSentinel in my logs?

If you're seeing VitalSentinel requests in your server logs, it means your website is being monitored by one of our users. Our bots are designed to be lightweight and respectful of your server resources. If you have concerns, please contact us.

match the user agent in your logs
VitalSentinel Uptime Bot/1.0Uptime and SSL checks
VitalSentinel Synthetic Monitoring Bot/1.0.0Lighthouse performance audits
VitalSentinel Sitemap Scanner/1.0Sitemap discovery
VitalSentinel Bot/1.0Robots.txt monitoring

VitalSentinel Uptime Bot

HTTP/HTTPS uptime and availability monitoring

This bot performs periodic HTTP GET requests to check if your website is online and responding correctly. It monitors response times, SSL certificate validity, and HTTP status codes.

User Agent

VitalSentinel Uptime Bot/1.0 (+https://www.vitalsentinel.com/uptime-bot)

Request Frequency

Configurable by the website owner (1 minute or 5 minutes)

Behavior

  • Makes GET requests to configured URLs
  • Follows redirects (up to 10 hops)
  • Default timeout of 10 seconds per request
  • Verifies SSL certificate validity and expiration (hourly)
  • Records response time, DNS lookup time, connect time, and TLS handshake time
  • Does not execute JavaScript or load external resources
  • Does not store or cache page content

VitalSentinel Synthetic Monitoring Bot

Lighthouse performance audits and Core Web Vitals measurement

This bot runs Lighthouse audits from VitalSentinel's own infrastructure using headless Chromium. Tests run in a clean, controlled environment, so results stay consistent and comparable from one run to the next.

User Agent

mobile

Mozilla/5.0 (Linux; Android 11; moto g power (2022)) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/119.0.0.0 Mobile Safari/537.36 VitalSentinel Synthetic Monitoring Bot/1.0.0 (https://www.vitalsentinel.com/bot)

desktop

Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/119.0.0.0 Safari/537.36 VitalSentinel Synthetic Monitoring Bot/1.0.0 (https://www.vitalsentinel.com/bot)

Request Frequency

Configurable by the website owner (hourly, every 4/8/12/24 hours)

Behavior

  • Runs Lighthouse in headless Chromium
  • Runs tests from VitalSentinel's own servers
  • Full Lighthouse audits (Performance, Accessibility, Best Practices, SEO)
  • Tests both mobile and desktop viewports with realistic throttling
  • Mobile: 2x CPU slowdown, 100ms RTT, 5 Mbps down / 2.5 Mbps up
  • Desktop: No CPU slowdown, 20ms RTT, 25 Mbps down / 10 Mbps up
  • Measures Core Web Vitals and lab metrics (LCP, CLS, FCP, TBT, TTI, Speed Index)
  • Captures screenshots and filmstrip frames
  • Default timeout of 120 seconds per test

About RUM & Analytics Scripts

VitalSentinel also offers Real User Monitoring (RUM) and Web Analytics services. Both use JavaScript snippets that website owners install on their pages to collect performance metrics from real visitors. These scripts run in the visitor's browser and do not use a separate bot or crawler. They only collect data from actual page visits.

Other VitalSentinel Bots

We use additional bots for specific monitoring tasks:

Sitemap Scanner

VitalSentinel Sitemap Scanner/1.0 (+https://www.vitalsentinel.com/sitemap-bot)

Robots.txt Monitor

VitalSentinel Bot/1.0 (+https://www.vitalsentinel.com/bot)

How to Block Our Bots

If you wish to block VitalSentinel bots from accessing your website, you can add the following to your robots.txt file:

User-agent: VitalSentinel Uptime Bot
Disallow: /

User-agent: VitalSentinel Synthetic Monitoring Bot
Disallow: /

User-agent: VitalSentinel Sitemap Scanner
Disallow: /

User-agent: VitalSentinel Bot
Disallow: /

Note: If you block our bots, anyone who monitors your website with VitalSentinel will stop receiving results.

Questions or Concerns?

If you have any questions about our bots or believe our monitoring is causing issues with your website, please don't hesitate to contact us. We're happy to help.

This is what watching a site looks like

These bots run for someone else's website right now. The same checks can run for yours – uptime, Core Web Vitals, search, and analytics in one place.

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