How does Claude Sonnet 5's prompting guidance differ from Claude Sonnet 4.6's for verbosity?

Claude Sonnet 5's response length is calibrated to the perceived complexity of the task rather than defaulting to a fixed verbosity level regardless of how simple or complex the request actually is.

This is a more adaptive framing than treating verbosity as a single constant setting, and it means testing Sonnet 5's output length across a range of task complexities is more informative than testing it on one type of request and assuming the result generalizes.

Anthropic's own guidance notes that Sonnet 5 performs well out of the box on existing Sonnet 4.6 prompts, so this shift in verbosity behavior is framed as an underlying model characteristic to be aware of during testing, not necessarily something that requires immediate prompt rewrites unless a specific product's output length expectations are being missed.

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