Glossary

STDIO Transport

STDIO transport allows MCP servers to run as local processes that communicate with AI clients through standard input (stdin) and standard output (stdout). This is ideal for developer tools, CLI integrations, and local-first AI workflows.

Explanation

STDIO transport is the simplest way to connect an MCP server to an AI client. The AI client spawns your server as a child process and communicates by writing JSON-RPC messages to stdin and reading responses from stdout. There's no network involved — everything stays on the user's machine. This makes STDIO transport perfect for developer tools (code analyzers, linters, project managers), personal automation scripts, sensitive data processing that shouldn't leave the machine, and rapid prototyping. STDIO servers start instantly with zero configuration — no ports, no TLS, no authentication needed. Many developers start with STDIO for development and add HTTP transport later for production deployment.

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