Basic Debugging From Netsuite - acumenbrands/rest_suite GitHub Wiki
If you just want some basic feedback during the execution of any of the uploaded & deployed scripts you can use this:
nlapiLogExecution( 'EMERGENCY', "Title", "Details");
Then look in the Execution log for the script that you added this too.
You can also log variable states like this:
var test = '3';
nlapiLogExecution( 'EMERGENCY', "Title", test);
Also you can log array/objects to string like this:
nlapiLogExecution( 'EMERGENCY', "Title", JSON.stringify(resultsBlock));