Anthropic has long been warning about these risks—so much so that in 2023, the company pledged to not release certain models until it had developed safety measures capable of constraining them. Now this system,

Claude 4 Sonnet is a leaner model, with improvements built on Anthropic's Claude 3.7 Sonnet model. The 3.7 model often had problems with overeagerness and sometimes did more than the person asked it to do, Amodei said. While it's a less resource-intensive model, it still performs well, he said.

Faced with the news it was set to be replaced, the AI tool threatened to blackmail the engineer in charge by revealing their extramarital affair.