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Claude Opus 4.1

AnthropicProprietaryPending Human Review

Claude Opus 4.1 is an independently released update to Opus 4, focused on agentic tasks, coding, and reasoning. The release improves multi-file refactoring and precise debugging while retaining the Opus pricing tier. It was accessible through Claude, the API, and cloud partners. Its API endpoint was subsequently retired in August 2026; the page preserves this significant historical weight update.

2025-08-05
Unreleased
Undisclosed proprietary architecture
Proprietary

Specifications

Parameters
Unreleased
Architecture
Undisclosed proprietary architecture
License
Proprietary
Context Window
200,000 tokens
Max Output
32,000 tokens
Type
multimodal
Modalities
textimage

Benchmark Scores

Advanced Specifications

Model Family
Claude
API Access
Not Available
Chat Interface
Available
Multilingual Support
Yes
Variants
claude-opus-4-1

Capabilities & Limitations

Capabilities
agentic codingreasoningdebuggingvision
Known Limitations
Can make factual or coding errors; tool results and important outputs require verification.Longer reasoning and agent work increase latency and token consumption.Retired from the Claude API on August 5, 2026.
Notable Use Cases
multi-file refactoringcode reviewtechnical reasoning
Function Calling Support
Yes
Tool Use Support
Yes

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