REST template pre-processing fields From the Pre Processing form of the activity designer, you can define a script to run before the activity executes. Table 1. Activity designer pre-processing fields Field Description Input process script Script to run before the activity executes. Variables Input variables that are available to use as building blocks in the input process script. Click the arrow above the field to open the variables list. Click an item in the tree to add it to your script in the appropriate syntax. The list displays execution parameters and input variables you passed into the activity on the Inputs form. All activity variables added in the Inputs form are read-only and are expressed in the pre-processing script with this syntax: activityInput.variable. Before the activity executes and makes a call to the service or host, you can override the effective execution value of this variable by assigning values to the executionParam.variable_name execution parameter. Refer to the specific execution parameters for your template.