Fix: MCP stdio transport broken by non-JSON startup output on stdout - #63
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disq wants to merge 1 commit into
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Fix: MCP stdio transport broken by non-JSON startup output on stdout#63disq wants to merge 1 commit into
disq wants to merge 1 commit into
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Run tsx directly instead of via npm start (npm echoes the script to stdout), and pass quiet: true to dotenv so its injection banner is suppressed. MCP clients require stdout to carry only JSON-RPC.
disq
marked this pull request as ready for review
August 19, 2026 13:11
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Issue
The Docker image writes non-JSON output to stdout on startup, so MCP clients on the stdio transport fail to parse it ("Unexpected token" errors in Claude Desktop). Two sources:
npm startechoes the script command, and dotenv v17 prints its injection banner.Solution
npx tsx src/cli.tsdirectly, bypassing npm's echo.NPM_CONFIG_UPDATE_NOTIFIER=falsesilences the npx update notice.dotenv.config()getsquiet: true.npm start.QA
initializerequest throughdocker run -i: stdout carries only the JSON-RPC response, stderr is empty.