Build a ChatGPT App

Master the new Apps SDK and build interactive applications that live right inside ChatGPT using the Model Context Protocol.

Why take this course?

The new Apps SDK is here, enabling you to put your product directly into the conversations of over 800 million ChatGPT users. In this hands-on challenge, you'll go beyond simple text bots to build a fully functional, interactive Todo List app that blends naturally with conversation. You will learn to build the Web Component frontend, create the backing MCP server, and use the open standard Apps SDK to wire it all together. Join the new era of AI-native development and ship your first ChatGPT App today.

Prerequisites

This course builds on concepts from the following courses. It is recommended to complete them first:

Model Context Protocol Fundamentals

Course Modules

1Step 1: The Challenge & Architecture

Learning Goals

Understand the "Hybrid Architecture": Web Component (Frontend) + MCP Server (Backend)
Grasp the "Apps SDK Trinity": User <-> ChatGPT <-> App
Learn the "Sandboxed Execution" model for security and isolation

2Step 2: The Frontend (Web Component)

Learning Goals

Understand the `window.openai` state injection model
Implement "Optimistic UI" for instant user feedback
Handle `openai:set_globals` for server-driven state synchronization

3Step 3: The Backend (MCP Server)

Learning Goals

Master the `text/html+skybridge` mime type and resource registration
Bind Tools to UI using `_meta` tags and output templates
Configure `StreamableHTTPServerTransport` for HTTP communication

4Step 4: Go Live! (Connect & Deploy)

Learning Goals

Master "Localhost Tunneling" to bridge local servers to cloud AI
Navigate the "Developer Mode" lifecycle: Edit -> Refresh -> Test
Validate "Tool Payloads" effectively during the development loop