This add-on sends browser history from the user's machine to a single
endpoint at https://cosmos.polarity-lab.com, the user's own cosmos
graph. The user opts in by minting a personal MCP key on the cosmos
website and pasting it into the add-on's Options page.

What gets sent. Per page that survives the client-side noise filter,
the add-on transmits the URL, the page title, the hostname, the
last-visit timestamp (ISO 8601), the visit count reported by the
browser, and the literal string "web" as a source label. Nothing else.

What does not get sent. Page bodies, cookies, form data, request
headers, IP address, browser fingerprint, user agent details beyond
what is implicit in any HTTPS request, search queries, tab content,
bookmarks, passwords, or any synced browser data.

Where the key lives. The cosmos MCP key is stored in the extension's
own chrome.storage.local namespace. It is transmitted only as the
X-MCP-Key HTTP header on the POST to cosmos.polarity-lab.com. It is
never written to chrome.storage.sync, never copied to remote storage,
and never shared with third parties. Clicking "clear" in the Options
page deletes the key and the watermark from local storage.

What gets filtered before any network call. Navigational noise
(inbox pages, social-feed root URLs, search result pages, untitled
tabs, OAuth callback URLs), the user's own deployed sites, and any
page whose title is shorter than 12 characters. The full noise list
is in shared/filter-rules.json in the source code.

Third parties. None. The add-on contacts no domain other than
cosmos.polarity-lab.com. There are no analytics SDKs, telemetry
beacons, error reporters, or advertising libraries.

Data retention on the server. Pages are stored in the user's cosmos
graph indefinitely until the user removes them or revokes the MCP
key. Revoking the key stops further ingestion. Deletion of past
ingested pages is performed by the user from the cosmos web app.

Contact. team@polarity-lab.com