Anthropic is releasing a new artificial intelligence model that is designed to code longer and more effectively than prior versions, its latest attempt to stay ahead of rivals like OpenAI in offering tools for software developers.
The new model, called Claude Sonnet 4.5, is better at following instructions and can code on its own for up to 30 hours straight, the company said on Monday. By comparison, a previous model called Claude Opus 4 is said to be able to field coding tasks for up to seven hours by itself. The updated version of Sonnet is also intended to excel at using a person’s computer to take actions for them, improving on a feature Anthropic introduced a year ago.
Anthropic has been an early leader in building so-called AI agents that field complex tasks on a user’s behalf, particularly for streamlining the process of writing and debugging code. The company, now valued at $183 billion, reached $5 billion in run-rate revenue in August, fueled in part by traction for its coding software. But other companies, including OpenAI and Alphabet Inc.’s Google, are also vying to win over programmers with similar capabilities. Anthropic’s latest release comes a week before OpenAI is set to hold its annual developer event.
Jared Kaplan, Anthropic’s co-founder and chief science officer, said Sonnet 4.5 is “stronger in almost every way” than its most recent high-end Opus model. Anthropic is also working to build a better version of the Opus model, which he expects will likely come out later this year. “We get benefits from having usage at both model sizes.”