OpenPencil

Open source vector design tool your coding agent can draw in through MCP

About

A design file your agent can actually open

The MCP server installs into Claude Code, Codex, OpenCode, Kiro or Copilot CLI in one click, so an agent can create and modify .op files, apply style guides and pull components from design system kits. Inside the app, an orchestrator splits a big page into sections and runs several agents in parallel, each drawing its own part. There is also an op CLI for batch edits from scripts, real time collaboration with pairing codes, and an embeddable read only viewer SDK. Things to know: the README carries sponsor banners for third party model API resellers, and you can ignore them and bring your own keys. New Windows installers sometimes trip antivirus heuristics, and the project documents how to verify downloads. MIT, about 6.3k GitHub stars, actively updated in October 2026.

Features

Prompt to canvas with streaming output
Built-in MCP server for Claude Code, Codex, OpenCode, Kiro and Copilot CLI
Git friendly JSON .op design files
Code export to React + Tailwind, HTML, Vue, Svelte, Flutter, SwiftUI, Compose, React Native
Parallel agent teams that draw different sections at once
op CLI, desktop apps for macOS, Windows and Linux, plus a web app

Install