Last updated: 5 July 2026
The Acrux — claude.ai companion browser extension does not collect, store, transmit, or sell any personal information or browsing content. There are no analytics, no tracking, and no remote servers operated by the developer.
The extension runs only on claude.ai. There it observes the timing of
response streaming — not the content of your conversations — to determine whether Claude is
currently generating a response or waiting on you.
When that state changes, the extension sends a single on/off signal to the Acrux desktop
application running on your own computer, over local loopback
(127.0.0.1). This request is authenticated by a pairing code you copy from the
desktop app. Your conversations, prompts, and responses are never read, stored, or transmitted.
No data is sent to the developer or to any third party.
host_permissions: https://claude.ai/* — run the detection script on claude.ai.host_permissions: http://127.0.0.1/* — deliver the on/off state to the local
desktop app's loopback server on your machine.storage — store your pairing code (port + token) locally on your machine.alarms — a watchdog timer so a missed end-of-stream can't leave the companion
stuck.The only data the extension stores is your local pairing code, kept in the browser's extension storage on your device. It never leaves your machine and is removed when you uninstall the extension.
Questions about this policy can be directed to the Acrux project maintainers at github.com/tekunlabs/acrux.