The Digester
technology

Anthropic accidentally publishes Claude Code source, exposing unreleased features and models

A debug file accidentally included in an npm package revealed the full Claude Code source and unreleased features, exposed internal model names, and may have distributed a remote access trojan to users who updated during the incident.

Mar 31st 2026 · United States

Insights

  • A debug file in the official npm package exposed the full Claude Code source, about 1,900 files and more than 512,000 lines of code.
  • Thousands of developers downloaded and began analyzing the leaked repository within hours.
  • The code reveals a 46,000-line conversation engine, roughly 40 action types and about 85 internal commands.
  • Unannounced features found in the code include BUDDY, a Tamagotchi-like virtual pet planned for May, and KAIROS, an always-on background assistant that logs observations and consolidates context.
  • The leak lists internal model names Capybara, Fennec and Numbat for upcoming or testing models.
  • Users who updated Claude Code via npm between 00:21 and 03:29 UTC may have installed a remote access trojan, and Anthropic advised checking affected dependency versions and migrating to the native installer with automatic updates.

Sources