From b695b2e9baa47d86acb747e695cfe1e3d642a0cc Mon Sep 17 00:00:00 2001 From: Jonathan Hefner Date: Sun, 25 Jan 2026 16:52:19 -0600 Subject: [PATCH] Improve README structure and clarity Add "Why MCP Apps?" section to explain the motivation upfront. Reorganize the "How It Works" section to lead with tool definition. Rename "Overview" to "Using the SDK" and add "For" prefix to audience headings. Restructure the Examples section with clearer subsections for running examples with `basic-host` vs MCP clients using stdio transport. Move the `qr` server note outside the collapsed details block. Co-Authored-By: Claude Opus 4.5 --- README.md | 57 ++++++++++++++++++++++++++++++++++--------------------- 1 file changed, 35 insertions(+), 22 deletions(-) diff --git a/README.md b/README.md index d4a5826c1..054682097 100644 --- a/README.md +++ b/README.md @@ -6,29 +6,33 @@ This repo contains the SDK and [specification](https://github.com/modelcontextpr MCP Apps are a proposed standard inspired by [MCP-UI](https://mcpui.dev/) and [OpenAI's Apps SDK](https://developers.openai.com/apps-sdk/) to allow MCP Servers to display interactive UI elements in conversational MCP clients / chatbots. +## Why MCP Apps? + +MCP tools return text and structured data. That works for many cases, but not when you need an interactive UI, like a chart, form, or video player. + +MCP Apps provide a standardized way to deliver interactive UIs from MCP servers. Your UI renders inline in the conversation, in context, in any compliant host. + ## How It Works -MCP Apps extend the Model Context Protocol to let servers deliver **interactive UIs** to MCP hosts. Here's how it works: +MCP Apps extend the Model Context Protocol by letting tools declare UI resources: -1. **Tool call** — The LLM calls a tool on your server -2. **UI Resource** — The tool's definition links to a predeclared `ui://` resource containing its HTML interface +1. **Tool definition** — Your tool declares a `ui://` resource containing its HTML interface +2. **Tool call** — The LLM calls the tool on your server 3. **Host renders** — The host fetches the resource and displays it in a sandboxed iframe 4. **Bidirectional communication** — The host passes tool data to the UI via notifications, and the UI can call other tools through the host -This enables dashboards, forms, visualizations, and other rich experiences inside chat interfaces. - -## Overview +## Using the SDK This SDK serves two audiences: -### App Developers +### For App Developers Build interactive UIs that run inside MCP-enabled chat clients. - **SDK for Apps**: `@modelcontextprotocol/ext-apps` — [API Docs](https://modelcontextprotocol.github.io/ext-apps/api/modules/app.html) - **React hooks**: `@modelcontextprotocol/ext-apps/react` — [API Docs](https://modelcontextprotocol.github.io/ext-apps/api/modules/_modelcontextprotocol_ext-apps_react.html) -### Host Developers +### For Host Developers Embed and communicate with MCP Apps in your chat application. @@ -57,6 +61,8 @@ For more information, including instructions for installing the skills in your f ## Examples +The [`examples/`](https://github.com/modelcontextprotocol/ext-apps/tree/main/examples) directory contains demo apps showcasing real-world use cases. + | | | | |:---:|:---:|:---:| @@ -78,12 +84,27 @@ For more information, including instructions for installing the skills in your f | [![Basic](examples/basic-server-react/grid-cell.png "Starter template")](https://github.com/modelcontextprotocol/ext-apps/tree/main/examples/basic-server-react) | The same app built with different frameworks — pick your favorite!

[React](https://github.com/modelcontextprotocol/ext-apps/tree/main/examples/basic-server-react) · [Vue](https://github.com/modelcontextprotocol/ext-apps/tree/main/examples/basic-server-vue) · [Svelte](https://github.com/modelcontextprotocol/ext-apps/tree/main/examples/basic-server-svelte) · [Preact](https://github.com/modelcontextprotocol/ext-apps/tree/main/examples/basic-server-preact) · [Solid](https://github.com/modelcontextprotocol/ext-apps/tree/main/examples/basic-server-solid) · [Vanilla JS](https://github.com/modelcontextprotocol/ext-apps/tree/main/examples/basic-server-vanillajs) | -The [`examples/`](https://github.com/modelcontextprotocol/ext-apps/tree/main/examples) directory contains additional demo apps showcasing real-world use cases. +### Running the Examples -
-MCP client configuration for all examples +#### With basic-host + +To run all examples locally using [basic-host](https://github.com/modelcontextprotocol/ext-apps/tree/main/examples/basic-host) (the reference host implementation included in this repo): -Add to your MCP client configuration (stdio transport): +```bash +git clone https://github.com/modelcontextprotocol/ext-apps.git +cd ext-apps +npm install +npm start +``` + +Then open http://localhost:8080/. + +#### With MCP Clients + +To use these examples with MCP clients that support the stdio transport (such as Claude Desktop or VS Code), add this MCP server configuration to your client's settings: + +
+MCP client configuration for all examples (using stdio) ```json { @@ -300,18 +321,10 @@ Add to your MCP client configuration (stdio transport): } ``` -> **Note:** The `qr` server requires cloning the repository first. See [qr-server README](examples/qr-server) for details. -
-To run all examples locally in dev mode: - -```bash -npm install -npm start -``` - -Then open http://localhost:8080/. +> [!NOTE] +> The `qr` server requires cloning the repository first. See [qr-server README](https://github.com/modelcontextprotocol/ext-apps/tree/main/examples/qr-server) for details. ## Resources