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日本語(JA) クロード・フェーブル 5.1: 「ブロックは別の会話にバインドされています」の解決

Anthropic's Claude Fable 5.1 adds "preserved thinking" to block distillation

By PulseAugur Editorial · [1 sources] ·

Anthropic has introduced a new security measure in its Claude Fable 5.1 model to prevent "distillation," a technique where models are trained on the outputs of other models. This new feature, called "preserved thinking," ensures that the conversation history used to generate a thinking block remains consistent. If the history is modified between requests, the model will reject the block, preventing unauthorized training on its outputs. This change primarily affects new accounts using the Claude API, Amazon Bedrock, Google Cloud, and Microsoft Foundry, though older accounts can opt-in. AI

IMPACT This change may impact developers building custom agent loops or chat backends that modify conversation history, requiring adjustments to maintain functionality.

RANK_REASON New model release with a novel security feature from a frontier lab. [lever_c_demoted from frontier_release: ic=1 ai=1.0]

Read on dev.to — LLM tag →

AI-generated summary · Google Gemini · from 1 sources. How we write summaries →

Anthropic's Claude Fable 5.1 adds "preserved thinking" to block distillation

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New model release with a novel security feature from a frontier lab. [lever_c_demoted from frontier_release: ic=1 ai=1.0]
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COVERAGE [1]

  1. dev.to — LLM tag TIER_1 日本語(JA) · Akira ·

    Claude Febr 5.1: Resolving "Block is bound to another conversation"

    <p>エージェントハーネスをClaude Fable 5.1に移行した後、思考ブロックが「別の会話にバインドされている」という400エラーを返すようになった場合、リクエスト間で会話履歴を編集している可能性があります。Fable 5.1は、この問題を検出して拒否する最初のClaudeモデルです。本稿では、チェックの仕組み、対象アカウント、発生条件、緊急回避策、そしてプロンプトキャッシュを維持する追記専用パターンを解説します。</p> <p><a class="crayons-btn crayons-btn--primary" href="https://a…

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