Build Codex skills for repeatable workflows

A Codex skill teaches a focused, repeatable workflow: tool sequence, decision points, output requirements, examples, and boundaries. The most useful implementation starts from a recognisable use case, defines the expected input and output, and separates reusable instructions from live systems that need MCP tools.

Setup path

How to approach this capability

1
Choose one well-defined use case and write a concise SKILL.md that states the trigger, workflow, output, and stop conditions.
2
Test direct, indirect, incomplete, and out-of-scope requests before packaging the skill with any required supporting resources.

Distribution decision

A plugin can contain one skill or a related group of skills and can declare required MCP dependencies.

Governance and safety

Do not combine unrelated workflows in one skill; split tasks with different inputs or success criteria.

First-party documentation

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Source checked Aug 16, 2026