Claude 4.5 Review: Anthropic's Agentic Generation That Broke 80% on SWE-bench

Claude 4.5 (Sonnet 4.5, Haiku 4.5, Opus 4.5) — released September–November 2025 — is Anthropic's agentic computing generation. Opus 4.5 hit 80.9% on SWE-bench Verified, the first model to break 80%. Haiku 4.5 brought extended thinking to the low-cost tier. All three feature hybrid reasoning and a programmable effort parameter.