Anthropic: Claude Opus 4.1

anthropic/claude-opus-4.1

Modalities: text+image+file->text
In / out price: $15 / $75
Context: 200K
Released: Aug 5, 2025
Knowledge cutoff: 2025-01-31

Claude Opus 4.1 is an updated version of Anthropic’s flagship model, offering improved performance in coding, reasoning, and agentic tasks. It achieves 74.5% on SWE-bench Verified and shows notable gains...

VisionToolsReasoningLong context

Supported parameters

include_reasoning
Include reasoning
Include a reasoning summary in the response.
max_tokens
Max tokens
Upper bound on generated tokens. Output stops at the limit.
reasoning
Reasoning
Enable or configure reasoning. The fields differ by model.
stop
Stop
Stop when these strings are produced. A string or an array of strings.
temperature
Temperature
Sampling temperature. Lower is steadier, higher is more varied. Often 0 to 2.
tool_choice
Tool choice
Whether to call a tool: auto, none, or a named function.
tools
Tools
Function definitions the model may call via tool_calls.
top_k
Top-K
Sample only from the K most likely tokens.
top_p
Top-p
Sample only from tokens whose cumulative probability reaches top_p.