What AlienMcp touches, and where it stays.

Last updated: September 7, 2026

The short version

AlienMcp collects nothing, transmits nothing, and stores nothing about you. It has no backend. Its only network destination is a WebSocket on ws://localhost:7888 to 7899, which is the MCP server you started on your own machine. The extension manifest pins connect-src to localhost, so reaching anywhere else is not a policy we promise to keep, it is something the browser will not permit.

What it can read, and when

Only while your own MCP client issues a tool call, and only for a tab you put in the AlienMcp tab group:

tab titles and URLs, so the assistant knows which page it is looking at
page content: DOM, visible text, screenshots, PDF exports
cookies for that site, when you ask whether you are still signed in
localStorage and sessionStorage for that site
network requests and console messages, while monitoring is on

All of it is returned over the loopback socket to the client on your machine, and nothing is written to disk by the extension.

Permissions

Permission	Why
tabs	List, open, activate and close tabs, and read a tab title and URL
scripting	Run the extension bundled functions in a page to click, fill, read or scroll
debugger	Chrome DevTools Protocol: screenshots, PDF export, console capture, network inspection, trusted keyboard and mouse input
cookies	Read or clear a cookie when you ask whether you are still signed in to a site
storage	The extension own connection state: the generated instance id that lets the local MCP server tell two Chrome profiles apart
alarms	Keepalive so the Manifest V3 service worker does not drop the local connection
tabGroups	Scope every tool to a tab group you create, so tabs outside it are invisible
<all_urls>	Operate on whichever site you point your assistant at

The extension declares no content scripts, so it injects nothing into pages you are merely browsing. Code runs in a tab only when a tool call names that tab.

As of version 1.2.0 the activeTab, webRequest and offscreen permissions were removed: they were declared but never used.

Retention

Nothing is persisted. Captured network requests and console messages are held in memory and cleared when the extension reloads or Chrome restarts.

Third parties

None. No analytics, no error reporting, no update server of ours, no bundled SDK. The source is MIT and readable, with no obfuscation and no minified vendor blobs.

Changes and contact

Changes to this policy are noted here and in the repository changelog. Questions go to an issue on GitHub.