Model Context Protocol (MCP): Definition & Governance

The Model Context Protocol (MCP) is an open standard that lets AI apps connect to tools and data through one shared interface. Instead of a custom integration for every pairing, an app that speaks MCP can use any MCP server. Anthropic introduced it on November 25, 2024.

A simple way to picture it

Think of USB-C. Before it, every device needed its own cable. MCP does the same for AI. Say you want Claude to read your database. You add a PostgreSQL MCP server, and Claude can list tables and run queries. The same server works in Cursor or ChatGPT, with no extra code.

The moving parts

MCP has three roles:

• The host is the AI app you use, like Claude Desktop or an IDE.
• The client is the connector inside the host. It holds one connection to one server. See MCP client.
• The server is the program that offers tools, resources (data) and prompts (templates).

Messages travel as JSON-RPC 2.0. They move over one of two transports: stdio for a server on your own machine, or Streamable HTTP for a server across the network.

Who runs it

MCP was designed at Anthropic by David Soria Parra and Justin Spahr-Summers. Block and Apollo were early adopters, along with dev-tool companies like Zed, Replit, Codeium and Sourcegraph.

As of September 2026, MCP is stewarded by the Agentic AI Foundation (AAIF), a fund under the Linux Foundation. Anthropic donated the project to it on December 9, 2025. Anthropic, Block and OpenAI co-founded it, with support from Google, Microsoft, AWS, Cloudflare and Bloomberg. Day-to-day technical decisions stay with MCP's own maintainers. Changes to the spec go through public proposals (SEPs), not one company's roadmap.

Where to go next

Running servers yourself is the hard part, so you can find them through a registry or use a hosted remote server. MCPifex is a hosted gateway on the same spec. You pick a server on the marketplace, and any MCP client that supports Streamable HTTP can connect to https://mcpifex.com/mcp. We run the server for you.

New to this? Read What is MCP? for the full walkthrough, or see how the spec has changed.