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pen.dev

Website

Agentic design canvas, formerly Pencil.dev, with desktop apps and VS Code/Cursor extensions. Agents design on the canvas directly, or through MCP and a CLI from Claude Code, Codex, Cursor and others. It imports .fig files and web pages as layers and exports frames as HTML with CSS/Tailwind.

Information

Type
AI-first
Usage
3.4%
Platform
MacWindowsLinux
Cost
$ 192
Pricing
Currently free; uses your own ChatGPT/Claude subscription or API key

Features

Yes
FreeFree plan
Yes
AIOn-canvas agents; MCP/CLI for coding agents
Partly
OfflineLocal .pen files; offline use not documented
Yes
Pen ToolPaths, curves, SVG paste
No
CollaborationShare links are view-only snapshots
CommentsNot confirmed
Yes
Handoff1-click HTML + CSS/Tailwind export
Yes
ArtboardsFrames on an infinite canvas
Yes
SymbolsComponents with overrides and slots
No
3D TransformNot documented
Yes
ResponsiveFill/hug/absolute layout
PrototypingNot confirmed

About pen.dev

pen.dev is a vector design tool built around AI agents, made by High Agency Inc. It was previously called pencil.dev. It runs as a desktop app for macOS, Windows and Linux, as an extension inside VS Code and Cursor, and as a headless command-line tool.

Designs are saved in .pen files, an open JSON format with a published schema, so coding agents can read and edit them directly. Agents such as Claude Code, Codex or Cursor connect through MCP, and the built-in agent can use your own model subscriptions or API keys. It imports .fig files and Figma clipboard content, and exports any frame as HTML with CSS or Tailwind.

In UX work it is mainly used by designers and developers who want UI layouts to live next to the code and be edited by agents.

Best for: Designers and developers who work with coding agents and want design files that sit in the codebase.

Strengths

  • Desktop app on macOS, Windows and Linux, plus VS Code and Cursor extensions.
  • Open JSON .pen format that agents can read and write.
  • Connects to external agents through MCP and a CLI.
  • Imports .fig files and pasted Figma layers.
  • One-click export of a frame to HTML and CSS or Tailwind.

Limitations

  • Real-time multiplayer editing is not described on the site; sharing is by link.
  • Prototyping and interactions are not documented.
  • The free plan limits agent use to 5 agent days and 25 image or SVG generations a month.

Pricing

Free plan at $0 with 5 agent days and 25 image/SVG generations per month. Pro is $16 per user per month and Ultra is $48 per user per month, with 20% off on annual billing; Enterprise is custom. Every plan can use your own agent subscriptions or API keys. Checked October 2026.

When to pick something else

  • Paper: pick it if you want another agent-connected design canvas
  • Figma: pick it if you need real-time team editing and a large plugin ecosystem
  • Google Stitch: pick it if you want prompt-to-UI generation in the browser
  • Penpot: pick it if you want an open-source, self-hostable design tool

Checked against pen.dev’s own website in October 2026.

pen.dev is a UI Design tool for Mac, Windows and Linux. A paid plan costs about $192 a year, and there is a free plan. In our comparison it supports AI, pen Tool, handoff, artboards, symbols and responsive. Offline is only partly supported. It does not offer collaboration and 3D Transform.

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