diff --git a/core/java/android/os/Bundle.java b/core/java/android/os/Bundle.java
index f215325f6be22..92eb7a5d047ef 100644
--- a/core/java/android/os/Bundle.java
+++ b/core/java/android/os/Bundle.java
@@ -33,6 +33,9 @@ import java.util.List;
 /**
  * A mapping from String keys to various {@link Parcelable} values.
  *
+ * <p><b>Warning:</b> Note that {@link Bundle} is a lazy container and as such it does NOT implement
+ * {@link #equals(Object)} or {@link #hashCode()}.
+ *
  * @see PersistableBundle
  */
 public final class Bundle extends BaseBundle implements Cloneable, Parcelable {
@@ -1230,6 +1233,10 @@ public final class Bundle extends BaseBundle implements Cloneable, Parcelable {
         maybePrefillHasFds();
     }
 
+    /**
+     * Returns a string representation of the {@link Bundle} that may be suitable for debugging. It
+     * won't print the internal map if its content hasn't been unparcelled.
+     */
     @Override
     public synchronized String toString() {
         if (mParcelledData != null) {
diff --git a/core/java/android/os/PersistableBundle.java b/core/java/android/os/PersistableBundle.java
index 76b88a3399d87..7b55e710caeb3 100644
--- a/core/java/android/os/PersistableBundle.java
+++ b/core/java/android/os/PersistableBundle.java
@@ -43,6 +43,9 @@ import java.util.ArrayList;
  * supported by this class is purposefully restricted to simple objects that can
  * safely be persisted to and restored from disk.
  *
+ * <p><b>Warning:</b> Note that {@link PersistableBundle} is a lazy container and as such it does
+ * NOT implement {@link #equals(Object)} or {@link #hashCode()}.
+ *
  * @see Bundle
  */
 public final class PersistableBundle extends BaseBundle implements Cloneable, Parcelable,
@@ -324,8 +327,12 @@ public final class PersistableBundle extends BaseBundle implements Cloneable, Pa
         return new PersistableBundle();  // An empty mutable PersistableBundle
     }
 
+    /**
+     * Returns a string representation of the {@link PersistableBundle} that may be suitable for
+     * debugging. It won't print the internal map if its content hasn't been unparcelled.
+     */
     @Override
-    synchronized public String toString() {
+    public synchronized String toString() {
         if (mParcelledData != null) {
             if (isEmptyParcel()) {
                 return "PersistableBundle[EMPTY_PARCEL]";