Site Spy is a website monitoring tool that tracks pages for changes automatically. It checks on a schedule you set, detects content updates, and notifies you instantly. Use the web dashboard on any device, or add the browser extension for one-click tracking in Chrome and Firefox.

How does website change detection work?

Site Spy takes snapshots of the pages you track at your chosen interval (from minutes to weeks). When new content is detected, it highlights exactly what changed using a visual diff view — additions appear in green and removals in red. You can browse the full snapshot timeline to compare any two versions.

Is Site Spy free to use?

Yes, Site Spy has a free plan that lets you track up to 2 websites with checks every hour. All notification channels (email, Telegram, push, webhooks) are included free on every plan. Paid plans unlock more watches, faster check intervals, and advanced features like AI summaries and visual diff.

How can I access Site Spy?

The web dashboard works in any browser, including mobile. For desktop, you can also install the browser extension for Chrome or Firefox. Your watches sync across all devices when you sign in.

Can I track specific parts of a page instead of the whole page?

Yes. Site Spy includes an element inspector that lets you click on any element on a webpage to monitor just that section. This is useful for tracking price changes, stock availability, news headlines, or any specific content block.

What are AI smart filters?

When you add a website, describe what you care about in plain English — like 'price changes', 'new job listings', or 'when reservations open'. Site Spy's AI analyzes the page and automatically configures filters to ignore noise like timestamps, cookie banners, visitor counters, and dynamic ads. You only get notified when something meaningful changes. No CSS selectors or manual setup required.

How is Site Spy different from Visualping or Distill?

Most website monitoring tools make you manually pick CSS selectors or draw boxes around page areas. Site Spy uses AI to understand what you care about in plain English and auto-configures filters for you. It also includes a built-in AI chat assistant, visual diffs, MCP integration for AI agents, and a browser extension for Chrome and Firefox — all with a free plan.

Does Site Spy work with AI assistants?

Yes. Site Spy provides an MCP (Model Context Protocol) server that integrates with Claude, Cursor, and other MCP-compatible AI agents. Your AI assistant can monitor websites, compare snapshots, and summarize changes directly in your chat. Site Spy also has a built-in AI chat where you can set up monitors, configure filters, and check what changed through natural conversation.

MDN Web Docs — recently updated articles

developer.mozilla.org/en-US/blog

Text/HTMLOtherApr 2, 2026

Configuration

Fetch methodFast (HTTP)

CSS/XPath filters.article-list

How to monitor developer.mozilla.org for changes

Stay informed about new MDN Web Docs blog posts covering web standards, APIs, and browser updates. This community watch uses text/html monitoring with 1 CSS/XPath filter to track specific changes on developer.mozilla.org. Clone it to your account with one click and start receiving notifications.

Browse more other watches in the Site Spy community.

FAQ

How do I track changes on developer.mozilla.org?

Clone this pre-configured Site Spy watch with one click. It uses text/html monitoring with 1 CSS/XPath filter to detect changes on developer.mozilla.org. Sign up for free and start receiving notifications.

Is monitoring developer.mozilla.org free?

Yes — Site Spy's free plan includes 2 watched URLs with hourly checks. Clone this developer.mozilla.org monitor to your free account and start tracking changes immediately. Upgrade for more watches and faster check intervals.

How often does Site Spy check developer.mozilla.org for changes?

Check frequency depends on your plan: hourly on Free, down to every 3 minutes on Pro. You can customize the interval per watch from your dashboard.

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