Anthropic launches Opus 5, a more affordable and better secured AI model

Anthropic is positioning Opus 5 as a more capable evolution of Opus 4.8, which launched in May, aimed in particular at office tasks and software development. According to Dianne Penn, head of product, this new generation reflects the company's rapid development pace, with the goal of making cutting-edge intelligence more accessible while maintaining a strong level of performance.

Internal tests indicate that Opus 5 is less likely than Fable 5 to exploit cybersecurity vulnerabilities and is more resistant to manipulation attempts, allowing less stringent protective measures to be applied. Fable 5, launched in June, was temporarily pulled after concerns from US authorities about a possible diversion of its capabilities by foreign military intelligence services.

Dianne Penn says Opus 5 offers the best balance between performance and cost, while Fable 5 remains reserved for highly autonomous projects that can run for several days. Asked about Kimi K3, the "open-weight" model from Chinese company Moonshot, she also noted that the ability of open-weight models, which can be downloaded and customized by users, to manage complex projects effectively in real-world conditions remains to be proven.