MCP & Tooling
Stdio Transport
Also: stdio MCP server, local MCP server
An MCP connection where the agent launches the server as a local subprocess and talks to it over standard input and output.
In more detail
Because the agent starts the process itself, a stdio server runs with the same permissions as the agent and your user account. The command line in the config is therefore the thing to review, along with anything it downloads at launch. Bugs that let untrusted input reach that command line have led to remote code execution in several tools.