# MCP Apps (spec and SDK)

> The official specification and SDK for MCP Apps: interactive UIs served by MCP servers inside AI chat clients.

## Facts
- **Category:** [MCP Servers](https://agentsearchengine.app/category/mcp-servers)
- **Type:** SDK / library
- **Pricing:** Open source
- **GitHub stars:** 2,865
- **Language:** TypeScript
- **License:** MIT AND Apache-2.0
- **Last repo activity:** 6 days ago (Sep 16, 2026)
- **Official site:** https://apps.extensions.modelcontextprotocol.io/
- **Source code:** https://github.com/modelcontextprotocol/ext-apps
- **Listing on Agent Search Engine:** https://agentsearchengine.app/agents/mcp-apps-sdk
- **Data verified:** September 2026

## Best for
Building tool UIs that work across every MCP Apps-compatible chat client.

## About MCP Apps (spec and SDK)
This official MCP repository holds the MCP Apps specification and SDK for building interactive interfaces, such as charts, forms and dashboards, that MCP servers render inline in Claude, ChatGPT and other compliant clients. It includes starter templates, examples and agent skills that scaffold a new MCP App or migrate an OpenAI Apps SDK app.

## Install

```
npm install -S @modelcontextprotocol/ext-apps
```

## Alternatives
MCP Apps (spec and SDK) sits in mcp servers. Related tools indexed here:
- [MCP Reference Servers](https://agentsearchengine.app/agents/mcp-reference-servers) — The MCP steering group's reference servers: Everything, Fetch, Filesystem, Git, Memory, Sequential Thinking and Time. · Open source · MCP server · 91k★ · TypeScript · MIT AND Apache-2.0 · active today
- [context7](https://agentsearchengine.app/agents/context7) — Context7 Platform -- Up-to-date code documentation for LLMs and AI code editors · Open source · MCP server · 62k★ · TypeScript · MIT · active today
- [chrome-devtools-mcp](https://agentsearchengine.app/agents/chrome-devtools-mcp) — Chrome DevTools for coding agents · Open source · MCP server · 53k★ · TypeScript · Apache-2.0 · active today
- [Playwright MCP](https://agentsearchengine.app/agents/playwright-mcp) — Expose Playwright browser tools to MCP clients using accessibility snapshots. · Open source · MCP server · 37k★ · TypeScript · Apache-2.0 · active 4 days ago
- [github-mcp-server](https://agentsearchengine.app/agents/github-mcp-server) — GitHub's official MCP Server · Open source · MCP server · 33k★ · Go · MIT · active today
- [serena](https://agentsearchengine.app/agents/serena) — A powerful MCP toolkit for coding, providing semantic retrieval and editing capabilities - the IDE for your agent · Open source · SDK / library · 30k★ · Python · MIT · active today
- [MCP for Blender (blender-mcp)](https://agentsearchengine.app/agents/blender-mcp) — Connect Blender to Claude or any LLM client for prompt-driven 3D modelling and scene editing. · Open source · MCP server · 29k★ · Python · MIT · active 2 days ago
- [fastmcp](https://agentsearchengine.app/agents/fastmcp) — The fast, Pythonic way to build MCP servers and clients. · Open source · SDK / library · 28k★ · Python · Apache-2.0 · active today

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