Logging & Diagnostics

#Daemon logging

The keep-alive daemon can tee its stdout/stderr (and per-server call traces) into a file so you can see crashes or repeated failures without rerunning it in the foreground.

#CLI flags

mcporter daemon start --log — enable logging at the default path ~/.mcporter/daemon/daemon-<config-hash>.log, or $XDG_STATE_HOME/mcporter/daemon/daemon-<config-hash>.log when XDG_STATE_HOME is set.
mcporter daemon start --log-file /tmp/mcporter-daemon.log — write logs to a specific file (path is created if needed).
mcporter daemon start --log-servers chrome-devtools,mobile-mcp — only emit per-call entries for the listed servers. Without this flag, --log records every keep-alive server’s calls.

mcporter daemon restart accepts the same logging flags, so you can bounce the daemon without retyping your tracing preferences.

Foreground mode (mcporter daemon start --foreground --log) still prints to your terminal; the log file mirrors the same content.

#Environment overrides

Set these before invoking mcporter (helpful for scripts/CI):

MCPORTER_DAEMON_LOG=1 — enable logging.
MCPORTER_DAEMON_LOG_PATH=/tmp/mcporter-daemon.log — custom log file.
MCPORTER_DAEMON_LOG_SERVERS=chrome-devtools,playwright — per-server call filtering.

The CLI flags take precedence; env vars are the fallback.

#Per-server opt-in

Add a logging block inside the server definition (alongside lifecycle) when you only want a specific STDIO transport to produce call traces, regardless of global flags:

"chrome-devtools": {
  "description": "Chrome DevTools protocol bridge",
  "command": "npx",
  "args": ["-y", "chrome-devtools-mcp@latest"],
  "lifecycle": "keep-alive",
  "logging": {
    "daemon": { "enabled": true }
  }
}

When combined with --log/MCPORTER_DAEMON_LOG=1, any server that has logging.daemon.enabled emits callTool start/success/error lines even if it isn’t listed in --log-servers.

#Inspecting logs

mcporter daemon status prints both the socket path and the current log file (if logging is enabled) so you can tail -f the output quickly.
Each call looks like:

`` [daemon] 2025-11-10T15:08:21.123Z callTool start server=chrome-devtools tool=take_snapshot [daemon] 2025-11-10T15:08:22.004Z callTool success server=chrome-devtools tool=take_snapshot ``

Shutdown events and errors are logged the same way (callTool error … err=..., listTools error …, etc.).

#Defaults & cleanup

Log files live under ~/.mcporter/daemon/ next to the socket/metadata, or under $XDG_STATE_HOME/mcporter/daemon/ when XDG_STATE_HOME is set. They’re not rotated automatically yet; delete/rotate them manually if they grow large. Running mcporter daemon stop leaves the log intact so you can inspect it after a crash.

#Foreground debugging

When troubleshooting deeply, run mcporter daemon start --foreground --log in a dedicated terminal. This keeps the daemon attached (so Ctrl+C stops it) and still writes to the configured log file for later inspection.