Claude Code leak explained: What Anthropic accidentally revealed

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Within hours, the massive 512,000-line TypeScript codebase was copied across GitHub and studied by thousands of developers.

For Anthropic, this is not just a small mistake. With a reported $19 billion annualized revenue run-rate as of March 2026, the leak is seen as a major loss of valuable intellectual property.

Developers found a three-layer memory system described as a "Self-Healing Memory" system.

The system also treats its own memory as a "hint," meaning it verifies information instead of blindly trusting it.

Also Read: Pentagon official sees little chance to revive Anthropic AI deal

The leak also revealed a feature called KAIROS which allows Claude Code to run as a background agent. Through a process called autoDream, the system improves and organizes its memory while the user is inactive and making it more efficient when work resumes.

Internal model details were also exposed, including codenames like Capybara, Fennec and Numbat. The data shows that even advanced models still face challenges with some versions having a higher false claims rate than earlier ones.

Another feature, "Undercover Mode," suggests the AI can contribute to public projects without revealing its identity. The system includes instructions such as, "You are operating UNDERCOVER... Your commit messages... MUST NOT contain ANY Anthropic-internal information. Do not blow your cover."