AGM-006: Nested AGENTS.md Hierarchy - AGENTS.md

Summary

• Rule ID: AGM-006
• Severity: MEDIUM
• Category: AGENTS.md
• Normative Level: BEST_PRACTICE
• Auto-Fix: No
• Verified On: 2026-02-09

Applicability

• Tool: all
• Version Range: unspecified
• Spec Revision: unspecified

Evidence Sources

• https://developers.openai.com/codex/guides/agents-md
• https://docs.cline.bot/prompting/cline-memory-bank#cline-memory-bank-custom-instructions-[copy-this]
• https://github.blog/changelog/2025-08-28-copilot-coding-agent-now-supports-agents-md-custom-instructions/

Test Coverage Metadata

• Unit tests: true
• Fixture tests: true
• E2E tests: false

Examples

The following examples demonstrate what triggers this rule and how to fix it.

Invalid

# Root AGENTS.md

Project instructions.

# src/AGENTS.md (nested, separate file)

Component-specific instructions that create hierarchy ambiguity.

Valid

# Project

Single AGENTS.md at the project root with all instructions.

## Commands

- npm test