Anthropic Introduces Claude Sonnet 5: Affordable and Efficient Agent Model

Anthropic has unveiled Claude Sonnet 5, a new mid-tier agent model that delivers performance close to its flagship Opus 4.8 but at less than half the cost. Announced on June 30, 2026, Sonnet 5 is now accessible across all plans. Designed with a focus on actionable intelligence, this model excels at performing tasks, not just providing answers.