Anthropic has revealed a 31.5% hijack rate for its Claude Opus 4.8 AI browser agent before safeguards are applied. This figure, detailed in the company's 244-page system card released on May 28, highlights the vulnerability of the model to prompt injection attacks when no defensive measures are active. The disclosure underscores the transparency gap among AI labs, as Anthropic is one of the few to provide such detailed security metrics. Post-safeguard testing on a related model, Opus 4.5, showed a significant reduction in attack success rates to approximately 1%, demonstrating the effectiveness of Anthropic's layered defenses. This data is particularly relevant for the crypto industry, where AI agents are increasingly integrated into trading bots and DeFi platforms. The pre-safeguard hijack rate serves as a caution for developers and investors in AI-adjacent crypto projects, emphasizing the need for robust security measures in real-world applications.