migration-guide changedmodels/sonnet-5-5/migration-guide
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1216* **Output format:** use [structured outputs](https://platform.claude.com/docs/en/build-with-claude/structured-outputs), or tools with enum fields for classification.
1216* **Output format:** use [structured outputs](https://platform.claude.com/docs/en/build-with-claude/structured-outputs), or tools with enum fields for classification. On Amazon Bedrock, structured outputs aren't available for Claude Sonnet 5.5. There, describe the format in the prompt or use a tool without `strict`, and validate the output in your code.
12171217* **Preambles:** ask in the system prompt for a direct answer.
12181218* **Unwanted refusals:** clear instructions in the user message are usually enough.
12191219* **Continuations:** move them to the user message, for example "Your previous response was interrupted and ended with `[previous_response]`. Continue from where you left off."
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