WebChangeDetector Bot
A visual regression testing bot that takes screenshots of websites to detect visual changes. This page documents our bot’s behavior, user-agent, IP address, and purpose.
Technical Details
What does this bot do?
The WebChangeDetector Bot visits web pages to take screenshots for visual comparison. It helps website owners detect unintended visual changes after updates, deployments, or third-party modifications. The bot only visits pages that website owners have explicitly added to their monitoring account. It does not follow links, discover new pages, or recursively crawl websites. Each request visits exactly one URL, takes a screenshot, and leaves.
User-Agent
The bot identifies itself with WebchangeDetector/1.0 appended to a standard Chrome user-agent string.
Desktop: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/116.0.0.0 Safari/537.36 WebchangeDetector/1.0
Mobile: Mozilla/5.0 (Linux; Android 10; K) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/116.0.0.0 Mobile Safari/537.36 WebchangeDetector/1.0
Desktop: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/116.0.0.0 Safari/537.36 WebchangeDetector/1.0
Mobile: Mozilla/5.0 (Linux; Android 10; K) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/116.0.0.0 Mobile Safari/537.36 WebchangeDetector/1.0
IP Address
The bot optionally operates from a static proxy IP address: 34.139.186.198. When the static proxy is not used, requests originate from Google Cloud Functions IP ranges in the us-east1 region.
Data Handling
Screenshots are stored securely in Google Cloud Storage and used exclusively for visual comparison purposes. Screenshots are not shared publicly and are only accessible to the website owner’s account. The bot blocks analytics tracking to avoid polluting website statistics.
Robots.txt Compliance
The WebChangeDetector Bot does not perform full-site crawling, so robots.txt rules do not typically apply to its operation. The bot only visits specific URLs that website owners have explicitly configured for monitoring. It does not discover, index, or follow links to other pages.
Bot Verification
The WebChangeDetector Bot can be verified by the WebchangeDetector/1.0 identifier in the user-agent string. When using the static proxy, requests originate from 34.139.186.198. Otherwise, requests come from Google Cloud Functions IPs in us-east1. The bot falls under the Monitoring & Analytics category.
Contact
If you have questions about the WebChangeDetector Bot or want to request changes to how it interacts with your website, please contact us at support@webchangedetector.com or visit webchangedetector.com.