What Is an MCP Server and How Does It Work?

It is a service that makes a system accessible to AI applications via the Model Context Protocol. The protocol lets the model use the system in a standardized manner, rather than requiring a separate integration for each application.

The client is the AI program that requires the tools or data. The server is an encapsulation of a particular system that offers its tools, resources, and prompts. The client communicates with the server using the protocol to make use of them.

Three main components are involved: tools (actions the model can perform), resources (data the model can access), and prompts (reusable templates). A client learns about them once it connects to the server.

Only if you trust it, since a server can take real actions and access data. A server should reveal only what is necessary, manage authentication correctly, and ideally be governed via a gateway that logs and controls access.

Not necessarily. Many servers are readily available for standard systems. You build your own when you need to interface a particular internal system in your company to AI applications, in a reusable, controlled way.