writing-great-skills
Reference for writing and editing skills well — the vocabulary and principles that make a skill predictable.
npx skills add fastagent-sh/fastagent --skill writing-great-skills --agent claude-code
Same command for any agent — swap --agent for codex, cursor, copilot.
Weekly change comes from our own snapshots, not the repository page — it measures attention, not adoption.
A skill exists to wrangle determinism out of a stochastic system. **Predictability** — the agent taking the same _process_ every run, not producing the same output — is the root virtue; every lever below serves it. **Bold terms** are defined in [`GLOSSARY.md`](GLOSSARY.md); look them up there for the full meaning. ## Invocation Two choices, trading different costs: - A **model-invoked** skill keeps a **description**, so the agent can fire it autonomously _and_ other skills can reach it (you can still type its name too). It contributes to **context load** — the description sits in the window every turn. Mechanics: omit `disable-model-invocation`, and write a model-facing description with rich trigger phrasing ("Use when the user wants…, mentions…"). - A **user-invoked** skill strips the description from the agent's reach: only you, typing its name, can invoke it — and no other skill can. Zero context load, but it spends **cognitive load**: _you_ are the index that must remember it exists. Mechanics: set `disable-model-invocation: true`; the `description` becomes human-facing — a one-line summary, trigger lists stripped. Pick model-invocation only when the agent must reach the skill
- Invocation
- Writing the description
- Information hierarchy
- When to split
- Pruning
- Leading words
- Failure modes
What does the writing-great-skills skill do?
Reference for writing and editing skills well — the vocabulary and principles that make a skill predictable.
How do I install it?
Run `npx skills add fastagent-sh/fastagent --skill writing-great-skills --agent claude-code` — it drops the skill into your project so the agent can pick it up. Swap the --agent value for codex, cursor or copilot if you use one of those.
Where does this skill come from?
From fastagent-sh/fastagent, a repository with 56 stars. We read it straight from the repository tree rather than a submitted listing, so what you see here is what is actually published.
Is a popular skill a good skill?
Not necessarily. Stars measure attention, not adoption — a repository can trend for a week and be abandoned. That is why we show the weekly change from our own snapshots next to the total, instead of a single flattering number.