Did an AI agent drive your browser while you were away? Chromium already knows

Posted on Oct 22 • Originally published at ccdeck.dev • AI-assisted

I build ccdeck. The step-by-step version of this post, with every setting, is at ccdeck.dev/guides/browser-watch.

More of my agents can drive a browser now: through an extension or through the browser's debugging protocol. Most of the time that is exactly what I asked for. But I leave agents running when I step away, and when I came back I had no way to answer a simple question:

Did something open pages in my browser while I was not there — and which ones?

The browser's history mixes those pages in with everything I opened myself. Some automated navigations carry a flag that can help separate them.

Every visit in a Chromium history database has a transition value that says how you got there — a link, a typed address, and so on. One qualifier, FROM_API ( 0x08000000, bit 27), marks certain navigations from an external application.

The distinction is narrower than “an API was used”:

Browser Watch tests that bit rather than trying to infer intent from a URL. The classification code and its Chromium source references document the distinction. This signal covers some browser activity; it is not a complete automation detector.

So a run of FROM_API visits, in a stretch when nobody opened a page by hand in that profile, is worth showing to the person who owns the browser. That is the whole idea behind Browser Watch, a panel in ccdeck.

It has no idle timer and does not watch your keyboard. It goes by the history alone.

Click the Browser watch eye in the toolbar, or press B. A badge counts the episodes that began since you last closed the panel.

The left column shows which browser profiles are watched, and how many pages a program opened in each since the deck started. On the right, Findings lists what a program opened while nobody was browsing.

Each card is one episode: one host in one browser. Click it to list every address the program opened, in full, with its time — the part after? and the part after # included.

A page counts only when it carries the FROM_API mark and there are no unmarked visits in that profile for the Nobody browsing for time — 15 minutes by default — before and after it. Until that time has passed, the card says provisional: an unmarked visit can still withdraw it, including one made by automation that does not set the flag. Pages stay in one episode while no two in a row are 15 minutes or more apart. The deck never reports its own tabs.

A finding is not a verdict. It is usually your own agent doing what you asked. The watch tells you what a program opened; the judgement is yours. Click × on a card you have checked and it leaves the list for good.

Demo data. This deck runs on Linux, so the menu holds notify me and quit the browser.

This panel reads your browsing history, so here is the precise list.

It is on by default. The Watch browser activity switch in the panel's footer starts on.

Only flagged episodes are kept, never your own browsing. The Live activity list counts your own pages without writing them down. And nothing from your history leaves the machine. What Browser Watch can access, under the gear, repeats this list in the panel itself.

When the watch is off, the background check reads no browser at all and nothing new is kept. Opening the panel still reads live — that is you looking — and shows only what this deck has seen since it started.

npx ccdeck Enter fullscreen mode Exit fullscreen mode With a deck page open, press B to inspect Browser Watch. A finding means a marked navigation met the quiet-window rule. An empty list does not establish that no program used the browser.