Head to head
Pencil (pen.dev) vs Gemini Canvas
Pencil (pen.dev) and Gemini Canvas solve the same job (AI design builders), so this is a pick-one decision. Pencil (pen.dev) is our default here: Names your exact stack as a first-class target — React + Tailwind + shadcn/ui. Draw the article template, and the drawing becomes real components. Because the .pen file lives beside the code, the design and the build cannot silently drift. Watch out: Requires a local checkout via Lovable's GitHub sync — cannot touch the browser editor. Domain is mid-rename (pencil.dev → pen.dev), early access, no published pricing commitment.
Quick read
- Editor's pick: Pencil (pen.dev).
- No logged gotchas: Gemini Canvas.
| Field | Pencil (pen.dev)pen.dev Not yet swept | Gemini Canvasgemini.google.com Not yet swept |
|---|---|---|
| What it is | A Figma-like canvas inside Cursor/VS Code/Windsurf, storing designs as JSON .pen files inside your project folder so they are git-versioned next to the code. Runs as an MCP server, so the agent reads the canvas as structured design context rather than as an image. Two-way: you can import existing components back onto the canvas. | A side panel where Gemini writes and iteratively edits an artifact with a live preview. For UI it defaults to a single HTML file with embedded CSS and vanilla JS; you can explicitly prompt for React instead. Copy from the Code tab is the only export mechanism. |
| Category | AI design builders | AI design builders |
| Cost tier | free | free |
| Pricing | Free during early access | Free · $7.99–$249.99/mo tiers |
| Why builders pick it | Names your exact stack as a first-class target — React + Tailwind + shadcn/ui. Draw the article template, and the drawing becomes real components. Because the .pen file lives beside the code, the design and the build cannot silently drift. | The cheapest way to test a UI idea before spending Lovable credits on it. No repo integration, no MCP, no awareness of your components — everything it writes is a self-contained island you reconcile by hand. |
| Watch out for | Requires a local checkout via Lovable's GitHub sync — cannot touch the browser editor. Domain is mid-rename (pencil.dev → pen.dev), early access, no published pricing commitment. | not logged |
| How to wire it up | MCP server; assumes Claude Code as the agent | not logged |
| Editor's pick | Yes | No |
Other matchups worth running
Agent endpoint: GET /api/public/compare?slugs=gemini-canvas,pencil