How we built Claude Code auto mode: a safer way to skip permissions

What this post added

Introduced 'Claude Code auto mode' as a new safety mechanism for AI agents. This mode uses model-based classifiers to automatically approve tool executions, reducing user fatigue from manual approvals while mitigating risks. It employs a two-layer defense: an input-layer prompt-injection probe and an output-layer transcript classifier. The classifier uses a fast single-token filter followed by chain-of-thought reasoning for flagged actions, focusing on detecting overeager behavior, honest mistakes, prompt injection, and misaligned models. The system defines trust boundaries and includes default block rules for destructive, security-degrading, cross-trust-boundary, and review-bypassing actions, with customizable allow exceptions.