What MCP-UI does
MCP-UI is a set of SDK packages that let an MCP tool return an interactive HTML interface instead of plain text, and let the host render it. It implements the MCP Apps standard: on the server side a tool is linked to a UI resource through _meta.ui.resourceUri, and on the client side AppRenderer fetches that resource and renders it in a sandboxed iframe.
Why teams reach for it: You reach for MCP-UI when you want both ends of an MCP Apps integration from one project: server SDKs in TypeScript, Python and Ruby that create the UI resource, React client components that render it, and an adapter that lets widgets written against the older MCP-UI postMessage protocol run inside MCP Apps hosts without code changes.
How MCP-UI compares
Fields the vendor doesn't document are left blank here rather than guessed — a blank means nothing verified, not a "no."
- Language
- TypeScript
- Official Sdk
- No
- Transports
- Not applicable
- Mcp Apps Support
- Yes
- Package Registry
- npm
- Package Name
- mcp-ui
What will you use to implement the protocol?
A framework or SDK gives developers pre-built code for creating an MCP server or client, so they don't have to implement the protocol from scratch.