diff --git a/lib/command/workers/runTests.js b/lib/command/workers/runTests.js
index a2ea9e409..0e67d25d0 100644
--- a/lib/command/workers/runTests.js
+++ b/lib/command/workers/runTests.js
@@ -145,7 +145,15 @@ function initializeListeners() {
 
       if (step.args) {
         for (const arg of step.args) {
-          arg && arg.$_root ? _args.push(JSON.stringify(arg).slice(0, 300)) : _args.push(arg);
+          // check if arg is a JOI object
+          if (arg && arg.$_root) {
+            _args.push(JSON.stringify(arg).slice(0, 300));
+          // check if arg is a function
+          } else if (arg && typeof arg === 'function') {
+            _args.push(arg.name);
+          } else {
+            _args.push(arg);
+          }
         }
       }