Claude Fable 5.1 cuts agreement openers 58% and em dashes 32%, Arena analysis finds
rohanpaul_ai · x · 2026-09-10
An analysis of tens of thousands of high-reasoning Text Arena outputs shows notable style shifts from Fable 5 to Fable 5.1:
- Agreement openers like "yes" and "exactly" fell 58%, from 2.35% to 0.99% of responses
- Honesty wording like "honestly" and "frankly" dropped 45% per 1,000 words
- Em dashes fell 32% per 1,000 words; praise dropped from 3.17% to 1.98%
- Semicolons rose 63% per 1,000 words, and answers have grown longer
Overall, Anthropic appears to be deliberately scrubbing the trademark "AI-isms" users have long complained about.
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