MCP (AI Agents)

ButterKit exposes a Model Context Protocol (MCP) server that lets AI agents control ButterKit programmatically. Use natural language in tools like Cursor, Claude Code, or OpenAI Codex to:

• Design screenshots from a prompt. Describe the look you want and let the agent create artboards, apply templates, set text, and configure 3D devices.
• Localize in bulk. Add languages and translate all screenshots and App Store metadata in a single command.
• Automate your release pipeline. Wire ButterKit into your CI/build process so screenshots update, translate, and upload to App Store Connect without manual work.
• Iterate fast. Ask for design tweaks, swap copy, preview renders, and export, all from your editor or terminal.

Video Tutorials

Claude AI Integration

OpenAI Codex AI Integration

Cursor AI Integration

Set Up Your AI Tool

Prerequisites

• ButterKit v1.8 or later. ButterKit doesn’t need to be open: since v2.0.08, the first tool call launches it. No document needs to be open either, since agents can open or create one.
• MCP must be enabled in ButterKit > Settings > AI Agents (MCP).
• No extra installation needed. ButterKit has an MCP bridge at ButterKit.app/Contents/MacOS/butterkit-mcp. When setting up your AI tool, you’ll point it to this path so it can communicate with ButterKit. The bridge’s source is on GitHub if you want to read exactly what runs on your Mac.

How It Works

Your AI tool connects to ButterKit through the MCP connector utility and gains access to 44 tools across 5 groups: Document, Design, Export, Localization, and App Store Connect. You describe what you want in natural language, and the AI agent calls the right tools automatically.

Reference

• Tool Reference (all 44 tools)
• Workflows (step-by-step recipes)

Launching ButterKit

When an agent calls a tool and ButterKit isn’t running, the helper launches it. To turn that off, switch off Allow agents to launch ButterKit in ButterKit > Settings > AI Agents (MCP); tool calls then return an error asking you to open ButterKit.

If ButterKit quits or updates during a session, your AI tool stays connected and picks ButterKit up again when it’s back. Older configs that pass --auto-launch keep working; the flag no longer changes anything.

Notes

• The MCP server renders artboards using ButterKit’s RealityKit engine. The app window does not need to be focused.
• All IDs (documentId, artboardId, templateId, etc.) are obtained from the corresponding list tools.
• Language codes follow ISO 639-1 (e.g. "en", "es", "ja"). App Store Connect locale codes follow Apple’s format (e.g. "en-US", "fr-FR").

Development builds: If you’re running a dev build from Xcode, replace /Applications/ButterKit.app with the path to your DerivedData build, e.g. ~/Library/Developer/Xcode/DerivedData/ButterKit-*/Build/Products/Debug/ButterKit.app.