tl;dr: Anthropic released Claude Sonnet 5, an agentic model that approaches Opus 4.8 performance at lower cost, with improved reasoning, tool use, and coding, plus longer autonomous task execution. Pricing starts at $2/M input and $10/M output tokens (introductory, through Aug 2026), rising to $3/$15 after; it's the default for Free/Pro plans and available via the Claude API. Safety evaluations show lower rates of misaligned behavior than Sonnet 4.6, and cyber safeguards are enabled by default despite the model being unable to develop full working exploits in testing.