Codex Skills vs AGENTS.md

AGENTS.md gives project-level guidance. It tells the agent how to behave inside a repository: code style, testing expectations, business rules, and constraints.

A skill gives task-level guidance. It tells the agent how to complete one repeatable workflow.

You want both. AGENTS.md sets the house rules. Skills provide the operating procedures for specific jobs.

For example, AGENTS.md might say "build mobile-first, run typecheck, avoid fake reviews." A skill might say exactly how to write a product comparison page or debug a checkout webhook.

What belongs in AGENTS.md?

AGENTS.md should describe the project itself. It is the right place for repo-wide context:

• Tech stack and package commands.
• Coding standards.
• Business rules.
• Files or directories the agent should avoid.
• Testing expectations.
• Design rules and product constraints.

The key is scope. AGENTS.md should help the agent behave correctly across the whole project.

What belongs in a skill?

A skill should describe one repeatable task. It should be narrow enough that the agent knows exactly when to use it and what output to produce.

Examples:

• Affiliate Product Review Writer.
• MVP Scope Cutter.
• Stripe Webhook Debugger.
• Local SEO Audit Skill.
• Anti-Hype Marketing Editor.

Those workflows should not be buried in AGENTS.md. If they are task-specific, they belong in a skill folder where they can be invoked, improved, and reused.

The clean setup

Use AGENTS.md for project rules. Use skills for repeated work. Use the current prompt for the specific inputs of the moment.

That gives the agent three layers of context:

1. The project rules.
2. The workflow method.
3. The current task details.

Every CodexSkills pack includes an AGENTS.md template plus task-specific skill folders. Start with the free starter pack, then browse all packs.