/
Published on 17.02.2026
TLDR: Anthropic shipped Sonnet 4.6 instead of the rumored Sonnet 5, and honestly, the version number is the least interesting part. This model closes the gap with Opus 4.6 on benchmarks like SWE-bench Verified while introducing granular thinking controls and a one-million-token context window in beta.
Link: No, It's Not Sonnet 5 (And That's a Good Thing): Meet Sonnet 4.6