# What is an MCP server?

An MCP server is a program that offers tools, resources and prompts to AI applications over the Model Context Protocol.

Updated on 22 October 2026.

## How it works

A local server runs on your computer and talks to the client over standard input and output; a remote server runs on the web and answers over HTTP. A remote server that holds private data asks the client to sign in, usually with OAuth.

The server describes each tool with a name, a description and the arguments it takes. The model decides when to call one, and the client can ask the person before it does.

## An example

A team’s documentation server offers search, read and write tools. In Cursor, a developer asks for the API conventions, and the agent calls the search tool, then the read tool, and answers from the team’s own spec.

## Common mistakes

- Running an unknown local server, which has your computer’s access.
- Pasting a long-lived key into a shared configuration file.
- Giving one connection access to more workspaces than the task needs.

## In Nodary

Nodary’s server is remote, at https://nodary.ai/api/mcp, over Streamable HTTP. Clients sign in with OAuth 2.1 (dynamic client registration and PKCE) or send an API key, and one connection can reach several workspaces, each call naming the one it works in. A connection makes up to 120 requests a minute, with no daily limit on writing, and a write retried with the same idempotency key never writes twice.

**What Nodary does not do:** there is no version of the server to run on your own computer or servers: it is hosted at nodary.ai.

- [The Nodary MCP server](https://nodary.ai/docs/mcp)
- [Connect Claude Code](https://nodary.ai/docs/mcp/claude-code)

Try it on your own documents. The Free plan needs no card. [Create a free workspace](https://nodary.ai/sign-up)

## Sources

- [Understanding MCP servers, modelcontextprotocol.io](https://modelcontextprotocol.io/docs/learn/server-concepts)
- [Authorization (MCP specification 2025-11-25), modelcontextprotocol.io](https://modelcontextprotocol.io/specification/2025-11-25/basic/authorization)
- [Authorization (MCP specification 2025-06-18, the version Nodary implements), modelcontextprotocol.io](https://modelcontextprotocol.io/specification/2025-06-18/basic/authorization)

## Related terms

- [MCP (Model Context Protocol)](https://nodary.ai/glossary/model-context-protocol): The Model Context Protocol (MCP) is an open standard that connects AI applications to outside tools and data through one common interface.
- [OAuth](https://nodary.ai/glossary/oauth): OAuth is a standard that lets an app act for you in another service, with access you approve, without ever seeing your password.
- [AI agent](https://nodary.ai/glossary/ai-agent): An AI agent is a language model that pursues a goal in steps, calling tools, reading their results and deciding what to do next.

https://nodary.ai/glossary/mcp-server