We’ve added [MCP Apps](https://github.com/modelcontextprotocol/ext-apps/blob/main/specification/draft/apps.mdx) (SEP-1865) support to the MCPJam Inspector, so you can now develop MCP Apps locally. We also merged a fix in the official SDK so it builds properly again, unblocking folks working on MCP Apps. 

For context, MCP Apps is the collaboration between MCP-UI, Anthropic, and OpenAI to create a unified spec for bringing interactive UI to MCP clients. 

🔍 **What’s in the preview:**

* UI preview in the Tools tab and LLM playground (similar to existing support for MCP-UI / ChatGPT apps)
* Support for external links, tool calling, and follow-up messages
* A sandboxed iFrame client implemented closely to the spec. We’d like community help to mature the client.

This dev tool should accelerate progress on the MCP Apps SDK and give developers an early way to build and test MCP Apps. It also serves as a good reference implementation for an MCP client with Apps support. 

🔗 GitHub: [https://github.com/MCPJam/inspector](https://github.com/MCPJam/inspector) 

🔗 Blog post: [https://www.mcpjam.com/blog/mcp-apps-preview](https://www.mcpjam.com/blog/mcp-apps-preview)

We built support for MCP Apps (SEP-1865) - test and debug MCP Apps UI