Skill Builder

Step-by-step guide for creating high-quality agent skills based on the open Agent Skills standard.

What is a skill

A skill is a portable folder containing instructions that teach an AI agent how to handle specific tasks or workflows. Instead of re-explaining preferences, processes, and domain expertise in every session, a skill captures that knowledge once and applies it consistently across interactions and platforms.

A skill contains:

• SKILL.md (required): instructions in Markdown with YAML frontmatter
• scripts/ (optional): executable code (Javascript, Bash, etc.)
• references/ (optional): documentation loaded as needed
• assets/ (optional): templates, fonts, icons used in output

Core design principles

Progressive disclosure: skills use a three-level loading system to minimize token usage while maintaining specialized expertise.

• Level 1 (YAML frontmatter): always loaded. Tells the agent when the skill is relevant.
• Level 2 (SKILL.md body): loaded when the agent determines the skill applies. Contains full instructions.