Anthropic's Claude Opus 4 outperforms OpenAI's GPT-4.1 with unprecedented seven-hour autonomous coding sessions and record-breaking 72.5% SWE-bench score, transforming AI from quick-response tool to day-long collaborator.

Claude Opus 4 is the world’s best coding model, Anthropic said. The company also released a safety report for the hybrid reasoning models.

Claude Opus is Anthropic's largest version of the model family with more power for longer, complex tasks, whereas Sonnet is generally speedier and more efficient. Claude Opus 4 is

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California-based AI company Anthropic just announced the new Claude 4 models. These are Claude Opus 4 and Claude Sonnet 4.

The company said it was taking the measures as a precaution and that the team had not yet determined if its newst model has crossed the benchmark that would require that protection.

A third-party research institute Anthropic partnered with to test Claude Opus 4 recommended against deploying an early version because it tends to "scheme."

Founded by former OpenAI engineers, Anthropic is currently concentrating its efforts on cutting-edge models that are particularly adept at generating lines of code, and used mainly by businesses and professionals.