Write or edit knowledge-base Markdown with frontmatter, Mermaid diagrams, related-document links, and markdownlint validation. Use for guides, specs, ADRs, runbooks, and API documentation; not repository meta files such as README, CHANGELOG, CLAUDE.md, AGENTS.md, or SKILL.md.
Install
npx skills add skrrt-sh/skills --skill md-writernpx skills add skrrt-sh/skills --skill md-writer -a claude-code -gnpx skills add skrrt-sh/skills --skill md-writer -a codex -ggemini skills install https://github.com/skrrt-sh/skills.git --path skills/docs/md-writergh skill install skrrt-sh/skills md-writergit clone --depth 1 https://github.com/skrrt-sh/skills /tmp/skrrt-sh__skills
mkdir -p ~/.claude/skills ~/.agents/skills
cp -R /tmp/skrrt-sh__skills/skills/docs/md-writer ~/.claude/skills/md-writer # Claude Code
cp -R /tmp/skrrt-sh__skills/skills/docs/md-writer ~/.agents/skills/md-writer # Codex, Cursor, Gemini CLI, Copilot, OpenCode