Claude Fable 5.1
by Anthropic
Claude Fable 5.1 improves on Claude Fable 5 across the board, with the biggest gains in agentic coding, long-running agentic workflows, and knowledge work: long code refactors, fro
Models
Claude Fable 5.1
Added 3 Sept 2026
Overview
Claude Fable 5.1 improves on Claude Fable 5 across the board, with the biggest gains in agentic coding, long-running agentic workflows, and knowledge work: long code refactors, front-end and visual...
How to use / API access
Call via OpenRouter with model id `anthropic/claude-fable-5.1`.
- openrouter ·
anthropic/claude-fable-5.1Docs
OpenRouter id: anthropic/claude-fable-5.1
Benchmarks
- Intelligence Index (artificial-analysis) : 53.4 index
- Coding Index (artificial-analysis) : 81.6 index
- Agentic Index (artificial-analysis) : 57.9 index
- Design Arena fullstack (other) : 1325 elo · #1
- Design Arena godotgamedev (other) : 1327 elo · #1
- Design Arena mobileapps (other) : 1268 elo · #4
- Design Arena python-pptxslides (other) : 1328 elo · #1
Notes
Claude Fable 5.1 is listed in the EDNA Models directory from the OpenRouter catalogue.
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