Shows Claude Code how to build slash commands from markdown files, covering the YAML frontmatter options, dynamic arguments with $1/$2 syntax, and file references with @ notation. The key insight here is that commands are instructions FOR Claude, not messages to users, which trips people up initially. You'll want this when you're setting up project workflows, creating reusable prompts with parameters, or need commands that execute bash inline to grab git status or environment context. It explains the difference between project commands in .claude/commands/ versus personal ones in ~/.claude/commands/, plus how to control tool access and model selection per command.
npx skills add https://github.com/aiskillstore/marketplace --skill command-development