diff --git a/google-cloud-clients/google-cloud-firestore/src/main/java/com/google/cloud/firestore/DocumentReference.java b/google-cloud-clients/google-cloud-firestore/src/main/java/com/google/cloud/firestore/DocumentReference.java
index 054fe5a1ab30..3a6e95b8ad33 100644
--- a/google-cloud-clients/google-cloud-firestore/src/main/java/com/google/cloud/firestore/DocumentReference.java
+++ b/google-cloud-clients/google-cloud-firestore/src/main/java/com/google/cloud/firestore/DocumentReference.java
@@ -360,6 +360,7 @@ public ApiFuture<DocumentSnapshot> get() {
    * @throws FirestoreException if the Iterable could not be initialized.
    * @return An Iterable that can be used to fetch all subcollections.
    */
+  @Nonnull
   public Iterable<CollectionReference> listCollections() {
     ListCollectionIdsRequest.Builder request = ListCollectionIdsRequest.newBuilder();
     request.setParent(path.toString());
@@ -402,10 +403,12 @@ public void remove() {
   /**
    * Fetches the subcollections that are direct children of this document.
    *
-   * @deprecated Use `listCollections()`.
+   * @deprecated Use {@link #listCollections()}.
    * @throws FirestoreException if the Iterable could not be initialized.
    * @return An Iterable that can be used to fetch all subcollections.
    */
+  @Deprecated
+  @Nonnull
   public Iterable<CollectionReference> getCollections() {
     return listCollections();
   }
diff --git a/google-cloud-clients/google-cloud-firestore/src/main/java/com/google/cloud/firestore/Firestore.java b/google-cloud-clients/google-cloud-firestore/src/main/java/com/google/cloud/firestore/Firestore.java
index 32d223f99a4d..cf1be3eb3826 100644
--- a/google-cloud-clients/google-cloud-firestore/src/main/java/com/google/cloud/firestore/Firestore.java
+++ b/google-cloud-clients/google-cloud-firestore/src/main/java/com/google/cloud/firestore/Firestore.java
@@ -55,10 +55,11 @@ public interface Firestore extends Service<FirestoreOptions>, AutoCloseable {
   /**
    * Fetches the root collections that are associated with this Firestore database.
    *
-   * @deprecated Use `listCollections()`.
+   * @deprecated Use {@link #listCollections()}.
    * @throws FirestoreException if the Iterable could not be initialized.
    * @return An Iterable that can be used to fetch all collections.
    */
+  @Deprecated
   @Nonnull
   Iterable<CollectionReference> getCollections();