Claude Sonnet 5

Claude Sonnet 5 Brings Opus-Class Agentic Capability to Default Deployment Tiers, Requiring Immediate Governance Reassessment

Anthropic released Claude Sonnet 5 on June 30, 2026, making it the default model for Free and Pro plans while also offering it to Max, Team, and Enterprise users. The model delivers agentic capabilities -- including autonomous browser use, terminal access, and multi-step task execution -- previously associated only with larger Opus-class models. Anthropic's safety assessments found lower rates of undesirable behaviors than its predecessor Sonnet 4.6, though the model's significantly expanded autonomous capabilities introduce new governance obligations for enterprise deployers.