Google AI Mode now offers Gemini 4 Argon to subscribers

Google calls Argon "just the beginning" of the Gemini 4 family. The announcement makes it available to developers and businesses through the paid tier of the Gemini API, to Ultra subscribers in Google's Antigravity coding tool, and to Pro and Ultra subscribers in the Gemini app and AI Mode. It does not say Argon replaces any model, and it does not mention AI Overviews.

Search Engine Roundtable reported that Google's Nick Fox and Robby Stein announced the AI Mode rollout on X, and, citing a user's post there, that Argon's answers in AI Mode include links to their sources. Links matter to a brand because they are how a cited page earns the visit.

Argon joins a menu rather than replacing what everyone sees. Google's AI Mode help page says subscribers can choose "Pro" from the menu in the Ask anything bar to use Gemini 3 Pro, while the "Fast" model "will continue to be helpful for fast, all-around assistance on most questions". In the UK the Pro option is offered in English to Google AI Plus, Pro and Ultra subscribers aged 18 and over, with daily usage limits.

The same thing happened in September. Gemini 3.8 Flash went into AI Mode on 2 September as an option Pro and Ultra subscribers pick from the plus icon, Search Engine Journal reported, and neither Google's launch post nor Robby Stein's post on X said whether it would become the default.

For your brand, that means two people asking AI Mode the same buying question can be answered by different models: one using the default, another a subscriber who picked Argon. You cannot see which model a customer used, and Google does not publish how often subscribers switch.

Discoverable's UK AI Shortlist Study put 1,000 buying questions to six consumer AI services on 6 and 7 September, Google AI Mode and Gemini among them. AI Mode did not name the business ranked first on Google in 61.7% of eligible answers (1,005 of 1,630). Gemini did not name it in 72.0% (1,171 of 1,627).

The study could not see which model answered most of its questions, so these are readings of the services as customers met them in early September, before Argon existed in either. Whether Argon names Google's leaders more or less often is unknown until the same kind of questions are put to it.

If you check AI Mode or Gemini without a Pro or Ultra subscription, carry on: Argon is not answering those checks. If you check while signed in to one of those plans, write down which model each answer came from, and mark 13 October in your notes so a shift in who gets named is not blamed on a page you or a competitor published.

If your buyers are the kind of people who pay for Google's AI plans, ask your most important buying questions in AI Mode twice, once with the default and once with Argon selected. Compare which businesses each answer names, what it says about yours and which pages it links to. A business named by one and not the other has learned something about the sources each model leans on.

For a quick reading of who AI names in your category today, the free AI visibility check asks buyer questions about your business on Claude with live web search, with no login, and shows who it names instead of you and the sources it cites. Our Google AI Mode tracker page explains how Discoverable reads AI Mode answers.