The Claude Code Source Leak: fake tools, frustration regexes, undercover mode, and more (10 minute read)

2026-04-01

This post analyzes the full source code of Anthropic's Claude Code, which was leaked via an npm package source map and revealed internal features like anti-distillation methods and a strategic product roadmap. While the leak exposed unreleased agent modes and client attestation plans, the real value lies in the revealed competitive intelligence rather than the code itself.