Intent Layer Hierarchical AGENTS.md infrastructure so agents navigate codebases like senior engineers. Core Principle Only ONE root context file. CLAUDE.md and AGENTS.md should NOT coexist at project root. Child AGENTS.md in subdirectories are encouraged for complex subsystems. Workflow When to Create Child Nodes | Signal | Action | |--------|--------| | 20k tokens in directory | Create AGENTS.md | | Responsibility shift | Create AGENTS.md | | Hidden contracts/invariants | Document in nearest ancestor | | Cross-cutting concern | Place at LCA | Do NOT create for: every directory, simple utilit…