modelsconfirmedimportance 4/5

Claude Sonnet 5 narrows the agentic capability and cost gap

Anthropic launched Sonnet 5 with stronger tool use, coding, reasoning, and configurable effort at a lower tier than Opus.

Occurred 2026-06-30Published 2026-06-30Verified 2026-07-17current
Why it matters

Agent architects can trade effort and token cost within one model family, but must remeasure tokenization and workflow economics.