Web Form - Input Validation - Change Default Field Names Shown

Hey all, 

Having a great time figuring out web forms - battled my way through the setup, post-submission code execution and now have gotten a lovely, useable, mobile-responsive landing page ready for use. 

My finalquestion is if there is a way to change the default error messages that show up during form input validation. To be specific, it's what you can see in the screenshot, the nice red box that pops up with "Field X is mandatory". 

Is anyone aware of if this is able to be named something else? Or am I going to have to look at making a fake field which writes to a ctx variable or something like that.

Thanks for your help!