tl;dr: Anthropic released Claude Opus 5.5, claiming frontier-level performance on coding, agentic tasks, and knowledge work while costing 40% less than Opus 5 ($4/$20 per million input/output tokens, $0.20 cache reads). The model reportedly matches or beats GPT-6 Astra on several benchmarks at a fraction of the cost, generates output 30% faster, and communicates more concisely. It ships with stricter safeguards for biology and cybersecurity (routing sensitive tasks to Opus 4.8), preserved-thinking anti-distillation protections, and is available on AWS, Google Cloud, and Azure.