Claude Opus 4 — Introduced

Anthropic introduced Claude Opus 4 on May 22, 2025, as part of the new Claude 4 generation. It was designed as Anthropic’s most capable model at the time, with a strong focus on advanced reasoning, coding, research, and complex multi-step tasks. Claude Opus 4 was particularly notable for its long-running reasoning and coding abilities. It could work through complicated software engineering problems, maintain context across extended tasks, and perform multiple steps toward a larger goal. Anthropic positioned Claude Opus 4 as a model for demanding professional and technical workloads, including advanced programming, research, analysis, and AI agent applications. Its release marked a major step forward in Anthropic’s development of highly capable AI systems.