Full Walkthrough: Writing & Using Skills — Nick Nisi and Zack Proser
Source
AI Engineer
Author
AI Engineer
Date
Terms in this piece · Glossary
agent skill — A reusable instruction file that teaches an agent how to do one job well — the procedure, the tools, and what counts as done.
AI agent — An AI system that doesn't just answer once but works toward a goal in a loop — taking actions, reading the results, and deciding what to do next.
Why it matters
Skills let you write a task-specific unit of AI agentAn AI system that doesn't just answer once but works toward a goal in a loop — taking actions, reading the results, and deciding what to do next.Full definition → behavior once and reuse it across Claude, Cursor, Codex, and your own agents without rewriting prompts — this walkthrough teaches the craft of writing composable skills and shows how they scale inside a real CLI built on the Claude Agent SDK.
Key quotes
“without scripts, the AI is just speculating on what you mean when you say, "Go get the latest commits."”
“It's a misnomer that skills are only a single markdown file.”
Nick Nisi
“I was making things worse because I was overly prescribing what to do with next JS and cloud code was just inherently good at working with next JS”
Nick Nisi
“all of that context is gold. Like the conversation, especially what failed, especially what didn't go well, especially what was frustrating”
Zack Proser
“I think I did a CD in a directory recently. Otherwise it's been like probably six or eight months now.”
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