diff --git a/tlatools/src/tlc2/tool/impl/Tool.java b/tlatools/src/tlc2/tool/impl/Tool.java
index 91e136dcdf2d6acea95908979cb2b2a2857508f8..c211acca5ef85bdb3134968042c9695830be6d9e 100644
--- a/tlatools/src/tlc2/tool/impl/Tool.java
+++ b/tlatools/src/tlc2/tool/impl/Tool.java
@@ -1640,6 +1640,9 @@ public abstract class Tool
             if (alen == 0) {
               if (val instanceof MethodValue) {
                 res = ((MethodValue)val).apply(EmptyArgs, EvalControl.Clear);
+              } else if (val instanceof EvaluatingValue) {
+            	  // Allow EvaluatingValue overwrites to have zero arity.
+            	  res = ((EvaluatingValue) val).eval(this, args, c, s0, s1, control, cm);
               }
             }
             else if (val instanceof Evaluator) {