What is a Skill?

Question

What is a Skill?

Accepted Answer

A Skill is a reusable workflow — a set of Guardrails, Steps, and Acceptance Criteria encoded in a SKILL.md file. Think of it as a QA Checklist: you apply it in any project, with any agent (Claude Code, Cursor, Copilot, Codex). It does not carry project-specific context.
A Subagent is an executor: it has a pinned model, specific tools, priorities, and an autonomous work plan. Subagents live in [docs-subagents](https://github.com/Docsbook-io/docs-subagents). They are built for a specific context and are not meant to be reused across projects.
Rule of thumb: "Would this workflow be useful in another project?" — yes → skill, no → subagent.

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