Anthropic launches Sonnet 5.5, a faster and lower-cost AI model focused on safety and alignment

Anthropic on Monday released a new artificial intelligence model called Sonnet 5.5, the company's second launch since CEO Dario Amodei called to slow down the pace of development.

Sonnet 5.5 is a faster, lower-cost offering from Anthropic, and the company said it is better at coding, completing scoped tasks and creating polished documents, slides and spreadsheets than its predecessor. The launch comes less than one week after Anthropic introduced Opus 5.5, a more expensive model, and it said Monday that Haiku 5.5, the cheapest offering in the suite, is coming soon.

"Sonnet is really for the cost-conscious customer where they might not need as much intelligence," Theo Chu, a research product manager at Anthropic, told CNBC in an interview. "It might be routine tasks that just need execution, but don't need that judgment that Opus can bring."

Anthropic's safety and security practices, as well as those of its competitors, have been under intense scrutiny in recent weeks after a growing chorus of researchers warned about AI's potential to cause catastrophic harm. In response, Amodei stunned the tech sector and government officials earlier this month by urging AI companies to slow how quickly they improve their most advanced models.

The company said Monday that Sonnet 5.5 doesn't advance the frontier of its models' capabilities, so most of its alignment testing focused on a "targeted set of risks that apply to models of any capability level," according to a blog post. In the AI industry, an aligned model is one that behaves in accordance with human interests and values.

However, Anthropic said that Sonnet 5.5 has cybersecurity capabilities that are a "large improvement" over those of its predecessor, so it's the first Sonnet model to launch with similar fallbacks and cyber safeguards that Anthropic has developed for its most capable models.

"Focusing on alignment and safety has been a key part of our mission from the very beginning," Chu said. "This is something that we've always prioritized across our models."

Sonnet 5.5 is available at $2 per million input tokens, and $10 per million output tokens, half the price of Opus 5.5. Anthropic said Sonnet 5.5 also requires fewer tokens per task than its previous version, which makes it cheaper to run.