Claude Opus 5

Claude Opus 5 is Anthropic's flagship reasoning model with a 1 million token context window, released in July 2026.

Strengths

Excels at complex reasoning, long-context analysis, and autonomous agent work across reasoning tasks, vision, and memory-dependent workflows.

Best for

Multi-step reasoning problems, extended document analysis, and agentic applications that benefit from a large context window.

Limitations

Superseded by Claude Opus 5.5 (released September 2026) for general reasoning workloads; consider the newer variant for current projects unless batch-mode processing is required.