To Set Error Breakpoints
To set the error parameter for the application, click the errors button.
in the Mule Breakpoints view.
This parameter causes any Event Processor in the application to become a breakpoint if it throws an error. In such a case, Studio stops flow execution at the event processor which threw the error, then displays the message in the Mule Debugger View.
Additionally, Studio identifies the error with a red, dotted-line square in the processor that failed during execution.