The Claude Code Source Leak: Fake Tools, Frustration Regexes, and Undercover Mode When developers reverse-engineered Claude Code’s compiled JavaScript bundle, they didn’t just find a system prompt. They found a window into how Anthropic thinks about AI behavior at the most granular level: placeholder tools that exist to shape cognition rather than perform actions, regex patterns monitoring your emotional state, and an identity-concealment layer built for whitelabel deployments. This is what Anthropic didn’t put in the docs. ...