Three-Layer Claude Code Extension Stack
- Entity ID:
ent-20260419-a7c9e1b3d5f7 - Type:
concept - Scope:
shared - Status:
active - Aliases: Core/Delegation/Extension layers, Crosley three-layer diagram
Description
Blake Crosley's architectural diagram of the Claude Code extension system as three stacked layers: (1) Core Layer — main conversation context with built-in tools (Read/Edit/Bash/Glob/Grep/etc.), where most users operate and where context bloat accrues; (2) Delegation Layer — up to 10 parallel subagents with isolated contexts that return summaries only; (3) Extension Layer — MCP, hooks, skills, and plugins providing external tools, deterministic automation, and domain expertise. Confirmed by the leaked source. Key insight: routing exploration/review subagents to cheaper tiers while keeping Core on Opus is the primary cost-optimization lever.
Key claims
- Four extensibility mechanisms sit at distinct context-cost tiers
Relations
- Three-Layer Claude Code Extension Stack --[supports]--> Five-Layer Architecture
- Three-Layer Claude Code Extension Stack --[owns]--> Blake Crosley