browser-sync-logger

This browser-sync plugin sends all console error logs to the terminal running browser sync

Launch from command line

npm install browser-sync-logger

node_modules/.bin/browser-sync start \
  --server . \
  --plugins browser-sync-logger

in bs-config.js, set

module.exports = {
  ...
  "plugins": ["browser-sync-logger"],
  ...
}

browser-sync start --server -c bs-config.js

and then in your client script, try

console.error("auth", 
    {"reason": "token validation failed."});

in the terminal that launched browser-sync, you should see

[ERROR] auth {reason: 'token validation failed'}