diff --git a/src/Chronos.php b/src/Chronos.php
index f03d8d71..30a271ac 100644
--- a/src/Chronos.php
+++ b/src/Chronos.php
@@ -190,6 +190,8 @@ public static function hasTestNow()
      */
     public function __debugInfo()
     {
+        // Conditionally add properties if state exists to avoid
+        // errors when using a debugger.
         $vars = get_object_vars($this);
 
         $properties = [
diff --git a/src/Date.php b/src/Date.php
index 7cfea762..387d0a94 100644
--- a/src/Date.php
+++ b/src/Date.php
@@ -133,6 +133,8 @@ public function toMutable()
      */
     public function __debugInfo()
     {
+        // Conditionally add properties if state exists to avoid
+        // errors when using a debugger.
         $vars = get_object_vars($this);
 
         $properties = [
diff --git a/src/MutableDate.php b/src/MutableDate.php
index 2cacf11c..00ea85bf 100644
--- a/src/MutableDate.php
+++ b/src/MutableDate.php
@@ -132,6 +132,8 @@ public function toImmutable()
      */
     public function __debugInfo()
     {
+        // Conditionally add properties if state exists to avoid
+        // errors when using a debugger.
         $vars = get_object_vars($this);
 
         $properties = [
diff --git a/src/MutableDateTime.php b/src/MutableDateTime.php
index 5b07a386..c97ffe18 100644
--- a/src/MutableDateTime.php
+++ b/src/MutableDateTime.php
@@ -175,6 +175,8 @@ public function __set($name, $value)
      */
     public function __debugInfo()
     {
+        // Conditionally add properties if state exists to avoid
+        // errors when using a debugger.
         $vars = get_object_vars($this);
 
         $properties = [