Instruction / Rule

Components

Instruction / Rule

Instructions are known to be the global rules an agent must respect when acting, whether it be practices to apply, how to develop, naming conventions, etc.

But it’s not just that: to avoid flooding the context with all instructions specific to languages or file types (markdown, java, go, etc.), specific instruction files can be created.

By doing that, the agent runtime only loads the frontmatter content into its context at the beginning of a session, and loads specific instructions only when working with the concerned files.

To avoid duplicating instructions between agent runtimes or files, @filepath references can be used within instructions to load specific files (e.g. @README.md, @AGENTS.md).

Important

Neutral standard from the Agentic AI Foundation.

Format: AGENTS.md
Read by: Codex, Copilot, Cursor, Mistral Vibe, Devin, Antigravity

repository/
└── AGENTS.md

Format: Claude Code

repository/
├── CLAUDE.md
└── .claude/
    └── rules/
        └── code-style.md

---
paths: ["src/api/**/*.ts"]
---

List of rules to respect for TypeScript API files

Format: Copilot

repository/
├── AGENTS.md
├── CLAUDE.md
├── GEMINI.md
└── .github/
    ├── copilot-instructions.md
    └── instructions/
        └── ruby-models.instructions.md

---
applyTo: "app/models/**/*.rb"
excludeAgent: code-review
---

Handle Ruby model files matching this pattern with the project's ActiveRecord conventions.

Format: Cursor

repository/
├── AGENTS.md
└── .cursor/
    └── rules/
        └── code-style.mdc

---
description: Rules for TypeScript API files
globs: src/api/**/*.ts
alwaysApply: false
---

List of rules to respect for TypeScript API files

Format: Hermes Agent

repository/
├── .hermes.md
├── AGENTS.override.md
├── AGENTS.md
├── CLAUDE.md
├── .cursorrules
└── src/
    └── api/
        └── AGENTS.md
~/.hermes/
└── SOUL.md

Precedence: .hermes.md > AGENTS.override.md > AGENTS.md > CLAUDE.md > .cursorrules.