diff --git a/src/main/java/com/google/devtools/build/lib/analysis/EmptyConfiguredTarget.java b/src/main/java/com/google/devtools/build/lib/analysis/EmptyConfiguredTarget.java
index 90ef920..eb33eb1 100644
--- a/src/main/java/com/google/devtools/build/lib/analysis/EmptyConfiguredTarget.java
+++ b/src/main/java/com/google/devtools/build/lib/analysis/EmptyConfiguredTarget.java
@@ -39,4 +39,9 @@
   protected Object rawGetSkylarkProvider(String providerKey) {
     return null;
   }
+
+  @Override
+  public String toString() {
+    return "Empty" + super.toString();
+  }
 }
diff --git a/src/main/java/com/google/devtools/build/skyframe/ValueOrException.java b/src/main/java/com/google/devtools/build/skyframe/ValueOrException.java
index e26cb1d..11d467e 100644
--- a/src/main/java/com/google/devtools/build/skyframe/ValueOrException.java
+++ b/src/main/java/com/google/devtools/build/skyframe/ValueOrException.java
@@ -77,6 +77,11 @@
       return null;
     }
 
+    @Override
+    public String toString() {
+      return "ValueOrExceptionValueImpl:" + value;
+    }
+
     @SuppressWarnings("unchecked")
     static <E extends Exception> ValueOrExceptionValueImpl<E> ofNullValue() {
       return (ValueOrExceptionValueImpl<E>) NULL;