AGENTS.md Format

AGENTS.md is a standardized markdown file that serves as a "README for AI coding agents" - providing dedicated, predictable context to help AI coding agents work effectively on a project.

Purpose

Unlike README.md (designed for humans), AGENTS.md contains:

• Build and test commands
• Code style guidelines
• Testing instructions
• Security considerations
• Any context a new teammate would need

Key principle: Give agents a clear, predictable place for instructions while keeping READMEs concise for human contributors.

Basic Structure

AGENTS.md is standard Markdown with no required fields:

# AGENTS.md

## Setup commands
- Install deps: `pnpm install`
- Start dev server: `pnpm dev`
- Run tests: `pnpm test`

## Code style
- TypeScript strict mode
- Single quotes, no semicolons
- Use functional patterns where possible

Simple First Approach

Default: Create one compact, lean AGENTS.md file. This satisfies most projects.

References folder (optional): Only create docs/agents/ when:

• Project has complex, project-specific patterns that need detailed explanation
• User explicitly wants separate reference files
• Content exceeds ~100 lines and cannot be condensed

Commands use AskUserQuestion to ask about references folder when appropriate.

Progressive Disclosure Pattern

Key Principle: Keep AGENTS.md lean by referencing detailed documentation instead of duplicating content inline.

Keep in AGENTS.md (inline):

• Essential commands (install, test, build)
• Critical conventions (quotes, semicolons, etc.)
• Security requirements (brief reminders)
• Brief project overview (1-2 sentences)

Move to references (only if needed, default: docs/agents/):

• Detailed architecture explanations
• Extensive code examples (>5 lines)
• Long-form documentation (>10 lines per section)
• Project-specific patterns and conventions

Example reference format:

## Testing instructions
- Unit tests: `pnpm test`
- E2E tests: `pnpm test:e2e`
See docs/agents/testing.md for detailed guidelines.

Cross-skill references: Use skill names instead of duplicating content from other domains:

## PR instructions
- Use Conventional Commits (see agd:conventional-commits skill)

Relative Path References for Subprojects

Use relative paths when referencing files within the same repository. This makes references portable and works from any subdirectory.

Syntax: Use paths relative to the file's location (e.g., ./relative/path/to/file.md)

Examples:

# In packages/api/AGENTS.md

## Architecture
See ../shared/architecture.md for shared patterns.

## Testing
See ../../docs/agents/testing.md for test guidelines.

Best practices:

• Use ./ for files in the same directory
• Use ../ to go up one directory level
• Use ../../ to go up two directory levels
• Keep paths short and intuitive

Cross-subproject references:

# In packages/web/AGENTS.md

## API Integration
See ../api/AGENTS.md for API conventions and patterns.

## Shared Components
See ../../packages/shared/components/ for shared UI components.

When to use:

• Documenting shared patterns between subprojects
• Referencing common utilities or libraries
• Linking to centralized documentation
• Avoiding duplication across monorepo structure

Implementation checklist:

• AGENTS.md under 100 lines (ideally 50-80)
• References folder only created if needed
• Essential commands remain inline

Recommended Sections

1. Project Overview: Brief description (1-2 sentences)
2. Dev Environment Setup: Essential commands
3. Testing Instructions: How to run and write tests
4. Code Style Guidelines: Conventions and patterns
5. PR/Commit Guidelines: Reference agd:conventional-commits skill
6. Security Considerations: Critical security reminders

See examples/basic-agents-md.md for a complete example.

Lifecycle Management

Commands

Command	Purpose	When to Use
/agd:init-agents-md	Create new from scratch	New project, no existing docs
/agd:migrate-agents-md	Convert from other format	Have AGENT.md, .cursorrules, etc.
/agd:update-agents-md	Update existing AGENTS.md	File exists but outdated

Decision Tree

No AGENTS.md exists? → Use init-agents-md
AGENT.md or other format exists? → Use migrate-agents-md
AGENTS.md exists but outdated? → Use update-agents-md

References Folder Decision

Commands use AskUserQuestion to ask about creating the references folder:

Ask when:

• Project has complex, project-specific patterns
• Content would benefit from detailed documentation
• User wants to add architecture diagrams, tutorials, etc.

Default path: docs/agents/

See references/lifecycle.md for detailed processes.

Agent Compatibility

AGENTS.md works across AI coding agents: OpenAI Codex, Cursor, Claude Code, Aider, Google Jules, Factory.

Symlinks: Create symbolic links for agent-specific files to maintain one source of truth:

• Claude Code: ln -s AGENTS.md CLAUDE.md
• Cursor: ln -s AGENTS.md .cursorrules
• Windsurf: ln -s AGENTS.md .windsurfrules

See references/agent-compatibility.md for tool-specific configs and monorepo patterns.

Migration

Automated

Use /agd:migrate-agents-md [source-file] to auto-detect and convert AGENT.md, .cursorrules, etc.

Manual

mv AGENT.md AGENTS.md
ln -s AGENTS.md AGENT.md  # backward compatibility

See examples/migration-example.md for a complete before/after example.

Best Practices

Do

• Keep it concise and scannable
• Use code blocks for commands
• Include actual commands agents can execute
• Treat it as living documentation
• Apply progressive disclosure

Don't

• Don't duplicate README content verbatim
• Don't include vague instructions
• Don't make it too long (agents work better with focused context)
• Don't forget to update as project evolves

Validation

After creating, migrating, or updating AGENTS.md, verify:

• All commands are executable
• File is concise (under 100 lines)
• Progressive disclosure applied
• No placeholder content
• Essential commands remain inline

See references/validation.md for comprehensive validation checklist.

Agent Behavior Rules

Rule	Behavior
No required fields	Use any structure that fits the project
Test execution	If tests listed, execute them before completing tasks
Living document	Update AGENTS.md as project evolves
Symlink prompt	Ask user about symlinks after creating AGENTS.md
References prompt	Use AskUserQuestion to ask about references folder when project is complex

References

• references/lifecycle.md - Detailed create/update/migrate processes
• references/agent-compatibility.md - Tool configs, symlinks, monorepo patterns
• references/validation.md - Comprehensive validation checklist
• examples/basic-agents-md.md - Complete working example
• examples/migration-example.md - Before/after migration example