Add messaging to custom web geoprocessing tool

[HamishMills]

Looking for information on how to add print messages to a gptool output in geoprocessing widget. 

Thanks! 

[BalajiVeera · Accepted solution]

If using in Python scripting, arcpy.AddMessage(message) & arcpy.AddError(message)

AddMessage—Help | ArcGIS Desktop 

[JeremyNicoletti1]

This solution no longer works for me. I used to use it before, but now I'm unsure if something was changed.