Claude Code Harness Architecture

Skill by ara.so — Claude Code Skills collection.

This skill provides deep architectural knowledge from the 420,000-word book "Decoding Agent Harness" (御舆:解码 Agent Harness), a comprehensive analysis of Claude Code's internal architecture. Use this to design, build, and debug production-grade AI Agent systems.

What This Covers

The book analyzes the complete Agent Harness architecture through 15 chapters:

• Conversation Loop: Async generator-based dialog control
• Tool System: 45+ tools, concurrent execution, safety protocols
• Permission Pipeline: 4-stage access control with speculative classification
• Context Management: 4-level progressive compression with circuit breakers
• Memory System: 4 types of closed-form memory, fork inheritance
• Hook System: 26 lifecycle events, 5 hook types
• Sub-Agents: Fork mode with byte-level context inheritance
• MCP Integration: 8 transport protocols, bridge architecture
• Skills & Plugins: 11 core skills, frontmatter-based loading
• Streaming Architecture: Performance optimization patterns