MCP
MCP — the Model Context Protocol — is an open protocol that lets an application built on a language model connect to external tools and data sources through one common interface.
It is the closest thing this field has to a settled standard. Anthropic published it in November 2024 and donated it in December 2025 to the Agentic AI Foundation, a fund under the Linux Foundation cofounded with Block and OpenAI, so it is no longer one company's protocol.
What problem does MCP solve?
Before it, every tool a model could use needed its own integration with every application that wanted to offer it. MCP replaces that with one interface: a tool implements an MCP server once, and any MCP client can use it.
The specification puts it plainly: MCP is «an open protocol that enables seamless integration between LLM applications and external data sources and tools». Everything else it does follows from that sentence.
Is MCP a real standard?
It is not issued by a standards body such as the IETF or the W3C, so calling it a formal standard would be wrong. What it has instead is multi-vendor governance: since December 2025 it belongs to the Agentic AI Foundation rather than to Anthropic.
For practical purposes that puts it in the strongest position of anything in this space. It is the difference between a specification a consortium maintains and one a single vendor can change on a Tuesday.
The gap is worth noting: 13 months passed between publication and the donation. A protocol that hands itself to a foundation that fast is behaving differently from one that keeps its options open.
Does MCP change anything on my website?
No, and this is worth saying because the question comes up constantly. MCP is a client-server protocol over JSON-RPC: it connects applications to tools. It defines no file you publish at your domain and no header you serve.
If you want to declare something to agents from your own site, the pieces that do that are an agent card, a rights reservation, or an index in Markdown — three different things, none of them MCP.
Where does this come from?
The specification itself and the announcement that opened it. Both public, both free to read in full.
- Model Context Protocol specification
The primary source, versioned by date. The sentence quoted above about integrating LLM applications with external data and tools comes from here.
- The original announcement, Anthropic
November 2024. Useful for dating the protocol and seeing what it set out to do before adoption widened.
- A2A specification
The sibling protocol, under the same foundation. Reading them together makes the split obvious: MCP connects a model to tools, A2A connects agents to each other.
Frequently asked questions about MCP
Do I need an MCP server for AI to cite my website?
- No. MCP connects applications to tools, and citation comes from crawlers reading published pages. An MCP server is useful when you want a model to act on your system, not when you want it to quote your content. The two are unrelated problems.
Who controls MCP now?
- The Agentic AI Foundation, a directed fund under the Linux Foundation, since December 2025. It was cofounded by Anthropic, Block and OpenAI, with backing from Google, Microsoft, AWS and others. Before that it belonged to Anthropic alone.