Boris Cherny highlights that Claude Opus 5 is the most resistant to prompt injection among Anthropic's models. This assessment is based on evaluations and red teaming results detailed in the model's system card.

  • Claude Opus 5 demonstrates high resistance to successful prompt injection attacks.
  • The finding is documented in the Claude Opus 5 System Card, specifically on page 73.
  • This security improvement is noted as more significant than standard evaluation scores.