> ## Documentation Index
> Fetch the complete documentation index at: https://docs.sitespy.app/llms.txt
> Use this file to discover all available pages before exploring further.

# Acknowledgements

> Open source projects that Site Spy is built on

Site Spy's detection engine is built on top of [changedetection.io](https://github.com/dgtlmoon/changedetection.io), an excellent open source website change detection tool. The core functionality — page fetching, diffing, and change detection — comes from their project.

What Site Spy adds on top:

* Browser extension with a visual element picker
* Browser-first workflow (install, connect, click what you want to watch)
* Hosted multi-user infrastructure with per-user API keys
* Billing and plan management
* MCP server for AI agent integrations
* Extended notification system (email, Telegram, browser push)

changedetection.io is actively maintained and free to self-host. If you prefer running your own instance, check out their project directly.