Pencil.dev

Overview

Pencil.dev is an AI-powered design canvas that integrates directly into development environments (particularly Cursor), enabling designers and developers to collaborate on visual interfaces without traditional design handoffs. It uses Claude AI to generate production-ready designs and code, with design files stored natively in Git alongside application code.

Key Architecture

• Agent-driven MCP canvas built around an open design format
• IDE-native: Available as both standalone desktop app and IDE extension
• Code repository integrated: Design files live in Git repos, enabling version control alongside code
• Pixel-perfect vector canvas with direct editor access—no separate design tool context switch

Core Features

Design Canvas with AI

• Pixel-perfect vector editor accessed directly in IDE
• Canvas-based prompting: Select screens/components and prompt Claude for design generation
• Direct design manipulation: Edit CSS properties, manipulate UI text, modify layouts live
• Production-ready output: Generated designs integrate seamlessly with code

AI Multiplayer Mode

• Multiple agents can generate screens/user flows in parallel
• Team can explore multiple design directions simultaneously
• Collaborative AI-assisted design iteration

Git-Native Version Control

• Design files stored alongside code in repository
• Full version control: branch, merge, commit designs like code
• Eliminates design file silos and keeps design/code synchronized

MCP Integration

• Full write access to MCP tools (not read-only)
• External data source integration: databases, APIs, chart data
• Browser automation support: Playwright, Puppeteer
• Extensible architecture to combine multiple agents

Figma Integration

• Can import polished vectors from Figma
• Supports design handoff from brainstorming to production implementation

Workflow Integration

“Design Mode for Cursor” philosophy:

• Optimized for “vibe coding” workflow—rapid AI-generated interfaces with visual design control
• Eliminates distinction between mockups and production in AI-driven development
• Designers maintain creative flexibility while leveraging AI acceleration during implementation

Use Cases

• Rapid UI prototyping with AI assistance
• Collaborative design and development workflow
• Version-controlled design files in development repos
• Multi-agent design exploration
• Integrating design data with databases and APIs

Requirements

• Claude Code subscription ($20/month) - Pencil acts as interface, Claude models handle generation
• Local Claude CLI instance - No browser version yet
• Currently free to use (early access stage)

Advantages

✓ Eliminates designer-developer handoff friction
✓ Git-native version control for designs
✓ AI-powered rapid iteration
✓ Maintains design precision in code
✓ IDE-native workflow
✓ Collaborative multi-agent design generation

Limitations

• Early access stage (evolving feature set)
• Requires Claude Code subscription dependency
• No browser version (local CLI only)
• Learning curve for Git-native design workflows

Related Tools

• Cursor - IDE integration point
• Claude AI - Underlying AI model
• Model Context Protocol - Extensibility framework
• Figma - Design import source

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Last updated: 2026-01-23