Anthropic Claude Sonnet 4.5 publicly released on: 2025-09-29 by Anthropic — production model improvements over Sonnet 4 with extended-thinking + better coding.
Subject
Anthropic Claude Sonnet 4.5
Predicate
publicly_released_on
Object
2025-09-29 by Anthropic — production model improvements over Sonnet 4 with extended-thinking + better coding