Unverified50% confidenceReleaseExact time
preserved thinking was released alongside Claude Fable 5.1 and Claude Opus 5.5.
1
Sources
50%
Confidence
Medium-term (~90 days)
Relevance
10/13/2026
First Seen
Valid until: 1/11/2027
Sources
Related Entities
Related Claims
UnverifiedOpus 5.5 is not Anthropic's flagship model; the true flagship is Claude Fable 5.1.73% similarUnverifiedOpus 5 is the flagship model of Anthropic's Claude series, known for its longer context window (capable of handling codebases of hundreds of thousands of tokens) and more cautious output style.69% similarUnverifiedClaude Fable 5 was released only 11 days after the previous generation Opus 4.8.68% similarUnverifiedExisting prompts written for Opus 5 run on Opus 5.5 without modification.68% similarUnverifiedFable 5 and Opus 5 are variants within the Claude model family with different positioning: the former tends toward efficient and concise responses, while the latter pursues depth and comprehensiveness.68% similar
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