source-command-create-rules

Use this skill when the user asks to run the migrated source command create-rules.

Command Template

Create Global Rules

Analyze the codebase and generate a AGENTS.md file with project-specific constraints and conventions.

Phase 1: Discover

Identify What Exists

Check for existing documentation:

• PRD.md, .codex/PRD.md — product spec
• README.md — project overview
• package.json, pyproject.toml, Cargo.toml — dependencies
• tsconfig.json, vite.config.*, next.config.* — build config
• Existing test files and patterns
• CI/CD workflows (.github/workflows/)
• Docker files

Identify Project Type

Map Structure

tree -L 3 -I 'node_modules|__pycache__|.git|dist|build|.next|venv*' 2>/dev/null || find . -maxdepth 3 -type f -not -path '*/node_modules/*' -not -path '*/.git/*' | head -60

Phase 2: Analyze

Extract Patterns (use sub-agents for research if needed)

From existing code, identify:

• Naming: files, functions, classes, variables
• Structure: how code is organized within files
• Errors: how errors are created and handled
• Types: how types/interfaces are defined
• Imports: relative vs absolute, named vs namespace
• Testing: framework, structure, patterns
• Logging: strategy and format

Research Best Practices

If this is a new project with a PRD but no code yet, spin up sub-agents to research:

• Testing strategy for the tech stack
• Logging best practices
• Common patterns for the framework
• Component/module organization conventions

Phase 3: Generate AGENTS.md

Write to AGENTS.md in the project root. Keep it under 500 lines.

Use this template as the output structure — fill in every section with real data from the codebase analysis:

@.codex/templates/CLAUDE-template.md

What NOT to include

• Exhaustive API documentation (put in .codex/docs/)
• Framework-specific guides (put in .codex/rules/)
• Full dependency lists (that's what package.json is for)
• Anything that isn't needed every single session

Phase 4: Create On-Demand Context (if patterns identified)

If the project has distinct subsystems, create on-demand rule files:

.codex/rules/
├── frontend.md      ← component patterns, styling conventions
├── api.md           ← endpoint patterns, middleware, auth
├── database.md      ← query patterns, migrations, schema
└── testing.md       ← mock patterns, fixtures, test utilities

Each file should have path-scoped frontmatter:

---
paths:
  - "src/frontend/**"
  - "src/components/**"
---

Output

Confirm:

1. AGENTS.md created with line count
2. Any .codex/rules/ files created
3. Any .codex/docs/ files created
4. What to review and customize