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MCPX_CONFIG_PARSE_ERROR

Severity: error Domain: Config

What happened​

mcpproxy reads ~/.mcpproxy/mcp_config.json (or the path you configured) on startup and on every change. The file failed JSON parsing — usually a trailing comma, an unquoted key, or a stray character.

mcpproxy refuses to start with a broken config rather than silently loading a partial state.

How to fix​

Validate the JSON​

jq . ~/.mcpproxy/mcp_config.json

jq will print the line/column of the first parse error. Common offenders:

  • Trailing comma after the last item in an array or object.
  • Smart quotes pasted from a doc tool instead of ".
  • Comment lines (JSON has no comments).
  • Two top-level objects without an enclosing wrapper.

Restore from backup​

mcpproxy writes .bak files when applying migrations / web-UI edits:

ls ~/.mcpproxy/*.bak
cp ~/.mcpproxy/mcp_config.json.bak ~/.mcpproxy/mcp_config.json

Edit via the web UI​

If you're not comfortable hand-editing JSON, edit through the web UI: it applies changes atomically and never leaves the file in a broken state.