What it is
The Model Context Protocol (MCP) is an open standard that lets AI applications connect to outside tools and data in one common way. An MCP server exposes things such as tools the model can call, data it can read and ready-made prompts; an AI application (the client) connects to it. It is often compared to a USB port: one plug shape, many devices.
What it is for
Giving an assistant safe access to your files, a database, a calendar, a code repository or a web service without writing a custom integration for each pair of assistant and service. Write a server once and any compatible assistant can use it.
How to do it
- Decide what the assistant needs: read some data, perform some actions, or both.
- Look for an existing MCP server for that service before writing one; many common services already have one.
- Add the server to your AI application's settings, following the application's documentation for how to register a server and give it credentials.
- Give the least access that works: read-only where possible, and only the folders or accounts the task needs.
- Ask the assistant to do a task that needs the tool, and check that it called the right tool with the right inputs; many applications ask you to approve each call.
- To build your own, describe in plain words the tools you want, and have an AI assistant write the server with an official MCP software development kit; then test it with the same steps.