Claude Opus 4.1 is Anthropic’s flagship model, offering improved performance in coding, reasoning, and agentic tasks. It achieves high scores on SWE-bench Verified and excels in multi-file code refactoring, debugging precision, and detail-oriented reasoning. The model supports extended thinking up to 64K tokens and is optimized for research, data analysis, and tool-assisted workflows.
Retired on Oct 1, 2026: requests to this model ID now return an error. These models are live and work with the same API key.
Claude Opus 4.1 is Anthropic’s flagship model, offering improved performance in coding, reasoning, and agentic tasks. It achieves high scores on SWE-bench Verified and excels in multi-file code refactoring, debugging precision, and detail-oriented reasoning.
No. Claude Opus 4 was retired on NagaAI on Oct 1, 2026, and requests to it now return an error. Live models you can use instead with the same API key: Claude Haiku 5.5, Claude Sonnet 5.5 and Claude Opus 5.5.
It takes text, images and files as input and returns text.
