01 Learn
Agent skills, explained plainly.
What a skill actually is, how it differs from MCP and subagents, what goes in a SKILL.md, and how to install one in whichever agent you use. Written by the team maintaining 51 of them in the open.
01 Start here · 10 min read
Explainer
What Is an AI Agent Skill?
A skill is a folder of instructions your AI agent loads on demand — a SKILL.md plus any scripts it needs. What goes in the folder, how the agent decides to load it, and why that beats pasting the same prompt every session.
02 What things are
The vocabulary, explained once and properly.
Two explainers 01 SKILL.md, Explained The anatomy of the one required file in an agent skill: every frontmatter field, why description decides whether your skill ever loads, how long the body should be — annotated with a real, shipping SKILL.md. 02 The Agent Skills Standard: One Format, Many Agents What agentskills.io is, what a shared skill format solves that per-vendor prompt files never could, what the specification actually defines, and how to tell whether an agent supports it — including what's still unsettled.
03 How they differ
The distinctions that decide what you should actually build.
Seven comparisons 01 Claude Skills vs MCP: Which One Do You Actually Need? A skill teaches an agent how to do something; MCP gives it a live connection to a system. Where each one wins, when MCP is genuinely the right answer, what they cost in context, and how to compose them. 02 Skills vs Subagents vs Slash Commands vs CLAUDE.md: What Goes Where Four ways to give a coding agent instructions, and one question that decides between them: what can you afford to have in context on every single turn? A practical map, with the context-window arithmetic. 03 Claude Code Skills Libraries: An Honest Roundup A fair comparison of the main open skills libraries for Claude Code and other agents — Superpowers, Corey Haines' marketing skills, Anthropic's official repo, book-derived collections, and ours — with straight guidance on which to install for which job. 04 Clean Code vs Clean Architecture: Same Author, Different Altitude Clean Code governs what happens inside a function; Clean Architecture governs which way dependencies point between modules. What each one actually rules on, why neither rescues the other, and which to reach for given a specific symptom. 05 Domain-Driven Design vs Clean Architecture: What Is the Boundary Drawn Around? DDD draws boundaries around meaning — bounded contexts, ubiquitous language, aggregates. Clean Architecture draws them around dependency direction. How they compose, what each one does that the other cannot, and when DDD is genuinely overkill. 06 Lean Startup vs Design Sprint: Which One Should You Run? One is a loop with no end date; the other is five days with a fixed agenda. What each actually produces, when a sprint is the cheaper way to buy the answer, when it is theatre, and how the two compose. 07 Positioning vs Messaging: Which One Is Actually Broken? Positioning is the context you choose; messaging is the words that follow from it. Why homepage rewrites so often change nothing, a symptom test that tells you which one is broken, and the order Obviously Awesome and StoryBrand run in.
04 How to do it
Practical steps, per agent.
Two how-tos 01 How to Install Claude Code Skills The practical install walkthrough: the one-line npx command, what --global really changes, where skills live in Claude, Claude Code, Claude Cowork, Codex, Cursor, OpenClaw and Hermes Agent, how to install by hand, and why a skill sometimes never triggers. 02 How to Write an Agent Skill A practical guide to authoring a skill that actually fires: choosing a triggerable scope, writing the description as a trigger rather than a summary, keeping the body short with the depth in reference files, and testing whether it changed the output.
You could keep prompting from scratch every time.
Or let 50 authors
do the thinking.
npx skills add wondelai/skills --all --global MIT licensed · Claude, Claude Code, Codex, Cursor, OpenClaw, Hermes · No account
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