Anthropic launched Claude Opus 5, its latest AI model for coding, professional work, and complex agent-based tasks, challenging OpenAI's GPT-5.6. The model sits below Fable 5 in Anthropic's lineup but is designed as a more practical option for regular professional use, approaching Fable 5 performance on several tasks while costing half as much through the API. Anthropic claims Opus 5 provides a major performance improvement over Opus 4.8, particularly for software engineering, research, data analysis and multi-step professional tasks. On the company's Frontier-Bench evaluation, Opus 5 reportedly achieved more than twice the performance of Opus 4.8 at a lower cost per completed task. At maximum effort on CursorBench 3.2, it performed within 0.5 percent of Fable 5's highest score while costing half as much per task. The model allows developers to control computational effort with options including low, medium, high, xhigh and max. Opus 5 supports a one-million-token context window and can generate outputs containing up to 128,000 tokens. Anthropic introduced mid-conversation tool changes and automatic fallbacks in beta. Claude Opus 5 costs $5 per million input tokens and $25 per million output tokens, matching Opus 4.8.