Building Your First AI Agent Skill: From Markdown to APIs

AI agent skills are easier to build than they look, and they scale from a simple markdown file to something that runs scripts and calls APIs. Here is a practical walkthrough of the whole spectrum, starting from the simplest useful skill.

Start simple: a markdown-only skill

The simplest skill is a folder with a single SKILL.md inside. No code. Just frontmatter and instructions.

code-reviewer/

SKILL.md