Question 1

What is a SKILL.md file?

Accepted Answer

A SKILL.md is the entry point of a Claude Code skill. It starts with a YAML frontmatter block delimited by --- containing a kebab-case name and a one-to-two sentence description, followed by a markdown body that tells Claude when to use the skill and the steps to run it.

Question 2

What makes a SKILL.md valid?

Accepted Answer

It must open with YAML frontmatter fenced by ---, include a name field in kebab-case (no spaces or uppercase, 64 characters or fewer), include a non-empty description (ideally one to two sentences, under ~1024 characters), and have at least one markdown heading in the body. A 'When to use' section is strongly recommended.

Question 3

How long should the description be?

Accepted Answer

One to two sentences works best. Claude reads the description to decide when to load the skill, so it should be specific about the trigger. The linter warns if the description is empty or longer than about 1024 characters.

Question 4

Does this tool send my SKILL.md anywhere?

Accepted Answer

No. Both generation and linting run entirely in your browser with JavaScript. Nothing you type is uploaded or stored on a server.

SKILL.md linter & generator

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