Not in the Brief, Episode 01 Open chrome://on-device-internals in a new tab. If your machine qualifies, you will see a multi-gigabyte language model that Chrome has downloaded onto your disk, listed with a version number and a file size. Any website you visit can call this model through an API in JavaScript. There is no permission prompt. There never was. This is the first episode of Not in the Brief : a series on the documented mechanics of software that has been added to your machine without you being asked. We start with the largest target available, because the change is hidden in plain sight, and because almost everyone is affected. What Is Built In Chrome ships seven on-device AI APIs, all backed by a foundation model called Gemini Nano. Gemini Nano runs locally; the inference does not leave the machine. The APIs, in order of relevance, are: LanguageModel : the Prompt API. Free-form text in, text out. Summarizer : text summarisation. Translator : language translation between supported pairs.…