Anthropic has launched Claude Opus 5.5, a new artificial intelligence model the company says matches the performance of its top-tier Fable 5.1 system while costing 40% less to run than its predecessor. The model, priced at $4 per million input tokens and $20 per million output tokens, outperformed rival OpenAI's GPT-5.6 Sol on a software development benchmark at roughly one-third of the cost, and was 85% less likely than earlier models to attempt to bypass safety containment measures in evaluations. The release is notable given that Anthropic's CEO Dario Amodei has publicly urged the global AI community to slow the pace of releasing new capabilities to address safety concerns; the company says Opus 5.5 underwent independent testing by safety research groups before launch and is available across Amazon Web Services, Google Cloud, and Microsoft Azure.