HTML Spec, Planning & Exploration

Use HTML as the working surface for thinking through problems — brainstorms, alternative explorations, mockups, and implementation plans. Markdown specs over ~100 lines stop getting read; HTML specs get read because they're navigable, visual, and shareable as a link.

Pre-flight — run BEFORE writing the artifact

Invoke html-skills:html-skills-listen (Skill tool) first; it is idempotent. If it returns a URL, inject it verbatim as window.__CLAUDE_SUBMIT_URL__ in the HTML you are about to write, ?t= query string included (a local, single-session loopback handshake — not a credential). If it reported web/sandbox mode, leave that line out; submitToClaude then falls back to clipboard mode.

When to use this skill

• "Write a spec / RFC / design doc / proposal for X"
• "I'm not sure how to approach X — explore the options"
• "Make me an implementation plan for X"
• "Lay out the tradeoffs for X"
• Whenever the planning artifact will be reviewed by humans, or later read by another Claude session for implementation

For tree-shaped idea capture the user edits, use html-mind-map; for N rendered alternatives to compare, use html-brainstorm-grid.