Congratulations! You've successfully implemented iframe-based UI components in your MCP server. You've moved from simple HTML and Remote DOM approaches to embedding full web applications that can leverage entire frameworks and provide rich, interactive experiences.
The key improvement is that your UI components now have access to the full
ecosystem of web technologies while maintaining secure communication with the
host application through the standardized postMessage protocol.
You learned how to create iframe-based UI resources using the
externalUrl content type, set up proper communication between iframe and host, handle lifecycle events, and implement responsive sizing. This approach gives you the flexibility to build sophisticated applications that would be cumbersome to maintain with raw HTML or Remote DOM.Let's keep moving to continue making the user experience even better with more advanced UI capabilities!