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OpenAI Apps SDK

ChatGPT App Studio

Build and preview ChatGPT Apps locally. A development workbench with live preview, mock tool responses, and production export.

chatgpt-app-studio-demo.vercel.app

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Everything you need to build ChatGPT Apps

Local development workbench with production-ready export

Live Preview

See your widgets render in real-time. Test across desktop, tablet, and mobile viewports with hot reload.

Mock Tool Responses

Simulate tool calls with configurable JSON responses. Test success, error, and edge cases without a backend.

MCP Server Scaffold

Optional MCP server template included. Run both frontend widget and backend tools with a single command.

Production Export

Export your widgets as self-contained HTML bundles with all dependencies inlined, ready for ChatGPT.

Display Modes

Preview inline, popup, and fullscreen modes. See exactly how your app will appear inside ChatGPT.

SDK Guide Assistant

Built-in AI assistant that knows the OpenAI Apps SDK docs. Get help with configuration and debugging.

How It Works

From scaffold to production in four steps.

1

Scaffold your project

Run the CLI to create a new project with the workbench, example widgets, and optionally an MCP server.

2

Develop your widgets

Build React components that use the window.openai SDK. The workbench provides live preview and hot reload.

3

Test with mock data

Configure mock tool responses to test different scenarios. Simulate user interactions and edge cases.

4

Export for production

Generate self-contained HTML bundles with all dependencies inlined. Deploy to ChatGPT with confidence.

Start building your ChatGPT App today.