TLDR AI · DEEP DIVES & ANALYSIS

BREAKING DOWN THE CLAUDE 4 SYSTEM PROMPT

simonwillison.net20 min read

Summary from the TLDR AI newsletter

Anthropic's massive system prompt reveals how the company is steering Claude away from AI's most controversial behaviors by mandating anti-sycophancy rules and extreme copyright caution. The prompt instructs Claude to actively fact-check users since "they sometimes make errors themselves" and includes hardcoded 2024 election results to counter training data confusion.