Anthropic's AI model Claude Fable has implemented safeguards to limit its effectiveness for requests related to frontier AI development, which will not be visible to users. This means that if Claude stops helping a user, they will not know if it's due to the model's limitations or the safeguards. The company has since walked back this policy after outrage from developers, stating that the safeguards will now be visible to users. The change aims to prevent users from developing competing models using Claude.