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MCP, explained in one drawing.

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    How MCP connects AI apps to tools Diagram. Four clients, Claude, ChatGPT, VS Code and Cursor, each connect to one MCP server. The server exposes tools, resources and prompts, and connects on to filesystem, github, postgres and slack. Transports are stdio for local and Streamable HTTP for remote. Claude ChatGPT VS Code Cursor MCP server tools resources prompts filesystem github postgres slack stdio for local Streamable HTTP for remote How MCP connects AI apps to tools Diagram. Four clients, Claude, ChatGPT, VS Code and Cursor, each connect down to one MCP server. The server exposes tools, resources and prompts, and connects on to filesystem, github, postgres and slack. Transports are stdio for local and Streamable HTTP for remote. Claude ChatGPT VS Code Cursor MCP server tools resources prompts filesystem github postgres slack stdio for local Streamable HTTP for remote

    M × N was the problem. M + N is the protocol.

    Point-to-point integrations versus MCP Diagram in two states. First, four apps wire directly to four tools, sixteen crossing lines, and the tangle is crossed out. Then the same apps and tools connect through one MCP server in the middle, eight clean lines. Claude ChatGPT VS Code Cursor filesystem github postgres slack MCP server

    10 apps × 10 tools, wired by hand 100 one-off connectors

    with MCP, 10 + 10 20 connectors, total

    The connectors do not disappear. Each one is written once, against the protocol, instead of once per pairing.

    An MCP server exposes three things.

    MCP, the Model Context Protocol, is an open standard for plugging tools and data into AI apps. Write a server once and Claude, ChatGPT, VS Code, and Cursor can all use it.

    tools

    Functions the model can call.

    search_issues(query)

    resources

    Data the model can read, addressed by URI.

    file:///repo/README.md

    prompts

    Prompt templates the user can invoke.

    /review-pr

    Transports: stdio for local servers, Streamable HTTP for remote.

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    move the pointer across this panel: the glue code is still underneath