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Simon Willison

Claude's new system prompt really doesn't want to reproduce song lyrics

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Anthropic has released the system prompts for its Claude consumer applications, including historic changes and an index structure that allows easy diffing of prompts. The latest update, seen in Fable 5.1, adds a comprehensive rule that Claude will not reproduce song lyrics, poems, or copyrighted passages, and will refuse any reworded requests thereafter, offering analysis instead. The prompts are accessible in Markdown via the platform.claude.com/docs site, facilitating transparent tracking of policy changes.

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