Skills and instructions
Learn when project rules belong in AGENTS.md, design decisions in design.md, and repeatable procedures in SKILL.md.
Learning
What each project-instruction file should do
Use design.md for visual decisions, AGENTS.md for rules a tool loads with the repo, and SKILL.md for a procedure.
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Agent skills: a practical guide
Understand when a reusable agent skill is useful and what belongs inside it.
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How to write SKILL.md
Write clear triggers, operating steps, references, scripts, and verification rules.
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A practical SKILL.md structure
See how hierarchy and instruction order affect whether an agent can follow a skill.
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Codex skills guide
Apply reusable skill folders in Codex with current, product-specific guidance.
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Why a Claude Code skill does not trigger
Diagnose discovery and trigger problems without assuming every agent loads instructions the same way.
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