transports

November 3, 20266 min

Fix "Unexpected token ... is not valid JSON" from a local MCP server

"Unexpected token ... is not valid JSON" in your MCP logs means a local server printed plain text on stdout, the channel reserved for protocol messages. Here is how to find the stray line and move it to stderr, from a quick terminal test to fixing your own server code.

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November 3, 20265 min

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Local or remote MCP server? How to tell them apart and which to use

A local MCP server is a program your AI app runs on your computer; a remote one is a web address you sign in to. How to tell them apart and which to pick.

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