# What is an MCP server?

An MCP server is a program that lets an AI assistant use an app. It speaks the Model Context Protocol, an open standard, and offers the app's actions as tools, such as search email or create a task, plus data the AI can read. Claude, ChatGPT and other AI apps connect once, then work in that app.

Updated 7 November 2026

## How does an MCP server work?

An MCP server works as a translator between an AI app and a service. The AI app, called the host, runs an MCP client for each server it connects to. When you connect, the client asks the server what it offers, and the server answers with three kinds of thing:

- **Tools:** actions the AI can take, such as `search_threads` or `create_draft`, each with a description and the inputs it needs.
- **Resources:** data the AI or the person can read, such as a document or a record.
- **Prompts:** ready-made instructions the person can pick, such as "summarise this thread".

The messages are JSON-RPC 2.0. The current version of the specification is dated 28 July 2026.

## What's the difference between a local and a remote MCP server?

A local MCP server runs on your own computer and is started by the AI app, which suits developers and tools that read local files. A remote MCP server runs on the service's side and is reached over the internet at an address, with a sign-in, usually OAuth. Remote servers are what most people use, because there's nothing to install: you paste an address into Claude or ChatGPT and sign in.

## What can you do with an MCP server?

You can ask your AI assistant to work in an app instead of copying text in and out. With an email server connected, "draft replies to everything a customer asked today" becomes one request. With a calendar server, "find a free hour with Sam" works. The more of your work an assistant can reach, the more useful it gets, which is why one server that reaches several apps beats one per app.

## How do you connect an MCP server to Claude or ChatGPT?

You add it as a connector. In Claude, go to Customize → Connectors, choose Add custom connector, paste the server's address and sign in. Developer tools such as Claude Code add servers with a command. The [Claude page](https://mojobase.ai/agents/claude) has the exact steps for Mojobase.

## Why does Mojobase have one MCP server for the whole business?

Because most small businesses keep their work in many apps, and an AI that sees one at a time can't join the dots. Mojobase's one MCP server reaches email, calendar, documents, tasks, customers, numbers and the Handbook through one address, under the same rules as the screens, and one search covers all of them. See how it compares with a single-app server on the [Gmail MCP page](https://mojobase.ai/mcp/gmail).

## Further reading

1. [Model Context Protocol specification](https://modelcontextprotocol.io/specification/latest)
2. [Gmail MCP server, Google for Developers](https://developers.google.com/workspace/gmail/api/guides/configure-mcp-server)
3. [Custom connectors using remote MCP, Claude Help Center](https://support.claude.com/en/articles/11175166-getting-started-with-custom-connectors-using-remote-mcp)

## Questions people ask

### What does MCP stand for?

Model Context Protocol. It's an open standard for connecting AI applications to the data and tools they need, using JSON-RPC messages between a client in the AI app and a server for each service.

### Is an MCP server the same as an API?

No, but it usually sits on top of one. An API is written for developers; an MCP server describes its tools in words an AI model can read, so the AI can decide when and how to use them.

### Do I need to install an MCP server?

Not for remote servers. A remote MCP server runs on the service's side, and you add its address to your AI app as a connector. Local servers run on your own computer and are mostly for developers.

### Is it safe to connect an MCP server?

Only connect servers you trust. The specification asks AI apps to get your consent before using a tool, and a good server only lets the AI do what you could do yourself, with a record of what it did.

## Related

- [MCP server](https://mojobase.ai/mcp)
- [Agents](https://mojobase.ai/agents)
- [Gmail MCP server for Claude, ChatGPT and your own agents](https://mojobase.ai/mcp/gmail)
- [Google Workspace MCP server for Claude, ChatGPT and your own agents](https://mojobase.ai/mcp/google-workspace)
- [Use Claude with your whole business](https://mojobase.ai/agents/claude)
- [The best MCP servers for a small business](https://mojobase.ai/blog/best-mcp-servers-for-small-business)

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Source: https://mojobase.ai/learn/what-is-an-mcp-server · Updated 7 November 2026