(Bloomberg) -- As Alphabet Inc.'s Google prepares for the coming launch of Gemini 4, it's grappling with internal skepticism over how well the flagship artificial intelligence model performs in key areas, such as coding.

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While Gemini 4 has performed well on benchmarks the industry uses to gauge model efficacy, it does less well when employees actually put it to work, according to people with direct access to the effort. The model struggles to handle certain coding tasks, said the people, who requested anonymity to discuss an internal matter.

Google has labored recently to develop models that can compete with OpenAI and Anthropic PBC. The company had planned to release a different version in June, dubbed Gemini 3.5 Pro, but abandoned the effort, the people said.

Google said it would be inaccurate to say that Gemini 4 is underperforming in areas such as coding. The company referred Bloomberg back to comments made last week by Koray Kavukcuoglu, the head of Google DeepMind who said he was encouraged by the model's performance.

"I have the utmost trust in the team," Kavukcuoglu said at a conference hosted by tech news site The Information. "In my mind, it's a certainty that we are always gonna be at the frontier."

There is a spectrum of opinion inside Google. Some employees believe Anthropic's Fable and OpenAI's Astra models are improving at a faster rate than Gemini. These people believe that Gemini 4 — even at its best — will still lag behind those models in some areas. Other employees believe the coming version has caught up with the leading AI labs.

A Google employee familiar with model development said there is "large consensus" internally at the company that Gemini 4 is at the frontier. This person said the company had conducted rigorous tests of the models and denied that they struggle with messy, real-world coding tasks.

Google badly needs Gemini 4 to succeed. Versions of the model underpin nearly every product the company sells, from the AI answers atop Search, Google's main profit engine, to Maps, Gmail and Chrome. Each of those products has more than a billion users, a distribution advantage some of the company's rivals lack.

But OpenAI and Anthropic are increasingly moving beyond selling models to building products of their own, including coding agents. Failing to deliver a cutting-edge model could give Google's competitors more time to convince consumers, developers and businesses that the future of search and software should run on their platforms instead.