Claude's new system prompt really doesn't want to reproduce song lyrics
Anthropic publish the system prompts for their Claude consumer applications ( Claude.ai and the Claude mobile apps - sadly not for Claude Cowork or Claude Code). I love that they do this, and that they share not just the current prompts but historic changes to their prompts as well. They used to keep all of…
Opening of the original on Simon Willison
Summary
Anthropic now publishes Claude's system prompts, allowing users to track changes. Simon Willison highlights that the latest prompts explicitly instruct Claude not to reproduce song lyrics. This transparency extends to historical prompt data, accessible via Markdown, making it easy to compare versions. The company also shares guidelines on answering style and cutoff dates.
Why it matters
Why it matters: Anthropic's commitment to publishing system prompts offers unprecedented transparency for consumer AI. This move allows users and researchers to directly observe how safety and output policies evolve. Competitors like Google Gemini and OpenAI do not offer this level of detail on their core model instructions. The explicit instruction against reproducing song lyrics suggests a focus on copyright and potentially reducing the generation of derivative content. This transparency benefits developers and users by clarifying model behavior and limitations.
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Rated low: routine. Worth knowing, not worth rearranging your day for.
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Questions people ask
- What new restriction does Claude's system prompt have?
- The latest system prompt for Claude explicitly instructs the AI not to reproduce song lyrics.
- Where can I find Claude's system prompts?
- Anthropic publishes system prompts for their Claude consumer applications on their platform.claude.com/docs site, including historical versions.
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Page generated Sep 3, 2026. Summaries are Subvolts' own; the story belongs to Simon Willison.