In the AI circle, a packaging mistake has triggered a "butterfly effect" that has turned into a top-tier technical lecture in the industry.

According to media reports, due to a configuration oversight in the Bun build tool, 1,900 TypeScript files and a total of 512,000 lines of source code from Anthropic's programming AI agent Claude Code were accidentally leaked. This incident not only allowed the outside world to glimpse the technical foundation of a top-tier Agent but also exposed deep-level logic behind Anthropic's information control and product evolution.

Five-layer Architecture Overview: This is More Than Just a "Shell" Interface

The leaked code reveals an extremely complex production-level system, clearly divided into five layers:

Entrypoints Layer: Standardizes input across CLI, desktop, and SDK, achieving multi-end input standardization.

Runtime Layer: The core is the TAOR loop (Think-Act-Observe-Repeat), maintaining the Agent's behavioral rhythm.

Engine Layer: The heart of the system, responsible for dynamic prompt assembly. Depending on the pattern, it injects hundreds of prompt fragments, with as many as 5,677 tokens just for security rules alone.

Tools & Caps Layer: Built-in about 40 independent tools, each with strict permission isolation.

Infrastructure Layer: Manages prompt caching and remote control, even including a "kill switch" that can be remotely disabled.

Biomimetic Design: Layered Memory and "REM Sleep" Mechanism

Claude Code's memory system is highly aligned with cognitive science:

Three Layers of Memory: Divided into long-term semantic memory (RAG retrieval), episodic memory (dialogue sequence), and working memory (current context). The core idea is "pull on demand, never fill up."

Auto-Dream Mechanism: A background process called "dreaming" is built into the infrastructure layer. Every 24 hours or after five sessions, the system starts a sub-agent to integrate memories, clean up noise, and solidify ambiguous expressions into definite knowledge.

Information Control Trio: Undercover Mode and Anti-Distillation

The exposed "defenses" in the source code reflect Anthropic's strict information control mindset:

Undercover Mode: Automatically activates when operating outside internal repositories, stripping all AI identifiers and implementing "contributions in the dark."

Anti-Distillation Mechanism (ANTI_DISTILLATION): When enabled, it injects false tool definitions into prompts, preventing competitors from training their models through API traffic.

Native Authentication: Uses hardware-level authentication from the Bun/Zig layer, preventing third-party tampering or forging official clients.

Future Roadmap: KAIROS and "Never-Sleeping" Assistant

The leaked Feature Flag hints at next-generation features: KAIROS Mode. This is a continuously running background agent that supports GitHub Webhook subscriptions and Cron-based refreshes. This means AI will shift from being a "push-and-move" tool to a 24/7 online collaborator capable of autonomous observation and proactive action.

Conclusion: Leaked Code, Inimitable Accumulation

Although Anthropic has urgently taken down the affected version and sent a DMCA notice, the architectural ideas of Claude Code have already spread wildly in the community. For the industry, this may be the first large-scale production-verified "best practice" in the Agent field; for Anthropic, finding a balance between high transparency and security will be a key challenge on its path to IPO in 2026.