# Model Context Protocol The Model Context Protocol (MCP) is an open protocol for connecting AI applications to external tools, resources, and prompts through a standardized client-server boundary. X/XApps and XDO are not MCP implementations. Their modern correspondence is architectural: X supplies named capabilities and host adapters; XDO composes them; a future adapter could expose selected contracts as MCP tools and selected documents or blocks as MCP resources. Related: [[wiki/Tool Contract|Tool Contract]], [[wiki/Resource Addressing|Resource Addressing]], [[wiki/Host Adapter|Host Adapter]], [[projects/X and XApps - Drop the Folder and It Runs|X and XApps]]. Sources: [Model Context Protocol specification](https://modelcontextprotocol.io/specification/draft/index), [Anthropic — Connect to local MCP servers](https://docs.anthropic.com/en/docs/mcp)