Anthropic launches Claude Opus 5.5 with lower Opus pricing and Fable-level performance claims

Anthropic introduced Claude Opus 5.5 on September 22, positioning the new flagship model as a cheaper, faster Opus-line release for long-running agentic coding and knowledge work. The company says the model performs at the level of Claude Fable 5.1 on most work while costing 40% less to run than Claude Opus 5 on typical workloads, with lower per-token prices and fewer tokens used per task.