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 50 of them in the open.

What things are

The vocabulary, explained once and properly.

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. 10 min read Anatomy 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. 8 min read Explainer · Open standard 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. 6 min read
How they differ

The distinctions that decide what you should actually build.

Comparison 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. 12 min read Comparison 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. 13 min read Comparison · Libraries 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. 8 min read Comparison · Craft vs structure 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. 8 min read Comparison · Meaning vs direction 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. 9 min read Comparison 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. 8 min read Comparison 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. 8 min read
How to do it

Practical steps, per agent.

How-to · Install 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. 8 min read How-to · Authoring 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. 9 min read
Prove it

Don’t guess your AI engineering level.
Measure it.

25 questions · ~8 min · Free

For hands-on developers

AI Developer Scorecard

How production-grade is your AI engineering?

Twenty-five questions across the practices that separate vibe-coding from production-grade engineering. Instant score, per-section breakdown, and a 30/60/90-day playbook.

Score 0–75 · 30/60/90-day playbook Score yourself For CTOs & founders

CTO Scorecard

Is your engineering team ready for AI at scale?

Twenty-five questions on how your org adopts AI — adoption, governance, automation, and ROI. See where you sit on the path from Reactive to Strategic Leader.

Score 0–75 · Reactive → Strategic Leader Score your org
Work with us

We build the skills you already use. Now we’ll build yours.

Custom skills · Subagents · MCP integrations — shipped to production, not demoed.

See what we build Book a 15-min call

Sprints from $3K · shipped to production, or you don’t pay the final milestone.