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fix: write startup errors to stderr - #14
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nanobot reads the server's stdout as the MCP stdio channel, so the startup error printed there was dropped as an unparseable message and logged only as: failed to unmarshal message: invalid character 'E'. On stderr, nanobot logs the actual error.
calvinmclean
approved these changes
Oct 6, 2026
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Problem
main.pyprints startup errors to stdout. nanobot reads the server's stdout as the MCP stdio channel, so it can't parse the message as JSON-RPC and drops it. All that shows up in the pod log is:That's what the WordPress server on our main environment is logging right now, after #13. Its config is missing the
WORDPRESS_*values, but the log doesn't say so.Fix
Print the startup error and the shutdown message to stderr. nanobot already forwards the server's stderr to its own log as
mcp stderr.Testing
I ran the image with no
WORDPRESS_*env (the same situation as main) and sentinitializeandtools/list:failed to unmarshal message: invalid character 'E' …msg="mcp stderr" … line="Error starting WordPress MCP Server: Required environment variable WORDPRESS_SITE is not set"