migrate-oai-app

This skill provides an automated and guided path for developers looking to port legacy OpenAI Apps SDK applications to the Model Context Protocol (MCP) Apps SDK (@modelcontextprotocol/ext-apps). It is designed for engineers and platform developers who need to transition from proprietary window.openai patterns to the standardized, open, and interactive UI protocol offered by MCP. The skill acts as a migration architect, ensuring that logic previously tied to the OpenAI runtime is correctly refactored for the MCP lifecycle.

• Step-by-step migration guidance for converting OpenAI Apps to MCP-compliant servers and UIs.

• Comprehensive API mapping tables for replacing legacy window.openai calls with modern app instances and handlers.

• Infrastructure guidance for modernizing server-side logic using registerAppTool and registerAppResource helpers.

• Automated workflows for Content Security Policy (CSP) auditing to identify necessary resource, connect, and frame domains before deployment.

• Integration support for major front-end frameworks including React, Vue, Svelte, Preact, and Solid.

• Best practices for managing app state and host context without relying on global window objects.

• Start by cloning the current SDK repository using the provided git commands to ensure you have the latest reference documentation and example server templates.

• Use the migration reference guide located at /tmp/mcp-ext-apps/docs/migrate_from_openai_apps.md for precise before-and-after mapping of your codebase.

• Always prioritize package manager-based dependency installation to ensure version compatibility instead of hardcoding version numbers.

• Perform a thorough CSP investigation by tracing all network origins in your existing build, categorizing them into resource, connect, and frame domains.

• Implement event handlers (ontoolinput, ontoolresult) before connecting to ensure reliable communication with the host environment.

• Be aware that certain features like widgetState or direct file uploads from OpenAI do not have direct MCP equivalents and require server-side state management patterns.

• Before finishing your migration, complete the explicit 'Before Finishing' checklist to ensure your app meets security and performance standards required by modern MCP hosts.