An MCP server is a small app that extends an AI model's capabilities by giving it access to custom tools, a particular set of data or workflows. It's based on the Model Context Protocol, which is an open standard for connecting AI apps with these external sources. The most straightforward way to create an MCP server is to use the official SDK, implement a single function and mark it as a tool and then expose it through stdio (standard input/output) which you can register in Claude Code; it ba...