Why server is not a server, but java -jar application?

[dims12]

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Discussion Topic

I am new to MCP and this has confused me from the quick start example (Java).

On one hand they claim they are writing MCP "server". On the other hand, what they specify in the configuration of Claude Desktop is not a server, but just a separate process, ran with java -jar.

What am I missing here?

Is this just a terminology? I.e. they call "server" which would better be called "plugin", i.e. an external program, that is ran by the AI tool?

Or it is really can be a server, i.e. something ran on remote computer and with which an AI tool can speak?

Sorry if the question is dumb.

[jssmith]

MCP supports presently specifies two transport mechanisms between the client and the server: 1/ stdio transport, 2/ HTTP with SSE transport. See the architecture.

Presently there is a lot more support for stdio, which functions as an external tool or plugin, than there is for SSE.

They key is that MCP has client-server model. Server is defined in this context simply as:
"A Server provides a service to the Client".