Claude Sonnet 5

Anthropic has released Claude Sonnet 5, a new model designed for autonomous agent tasks that matches the performance of the more expensive Opus 4.8 model while costing significantly less at $2 per million input tokens and $10 per million output tokens. The model shows substantial improvements over its predecessor Sonnet 4.6 in reasoning, tool use, coding, and planning capabilities, while maintaining improved safety profiles. Claude Sonnet 5 is now available across all plans as the default model for Free and Pro users.