diff --git a/gapic-google-cloud-storage-v2/src/main/java/com/google/storage/v2/stub/StorageStubSettings.java b/gapic-google-cloud-storage-v2/src/main/java/com/google/storage/v2/stub/StorageStubSettings.java
index e4787eb0c..1b42b3c7e 100644
--- a/gapic-google-cloud-storage-v2/src/main/java/com/google/storage/v2/stub/StorageStubSettings.java
+++ b/gapic-google-cloud-storage-v2/src/main/java/com/google/storage/v2/stub/StorageStubSettings.java
@@ -625,15 +625,6 @@ public StorageStub createStub() throws IOException {
             "Transport not supported: %s", getTransportChannelProvider().getTransportName()));
   }
 
-  /** Returns the endpoint set by the user or the the service's default endpoint. */
-  @Override
-  public String getEndpoint() {
-    if (super.getEndpoint() != null) {
-      return super.getEndpoint();
-    }
-    return getDefaultEndpoint();
-  }
-
   /** Returns the default service name. */
   @Override
   public String getServiceName() {
@@ -1340,15 +1331,6 @@ public UnaryCallSettings.Builder<GetHmacKeyRequest, HmacKeyMetadata> getHmacKeyS
       return updateHmacKeySettings;
     }
 
-    /** Returns the endpoint set by the user or the the service's default endpoint. */
-    @Override
-    public String getEndpoint() {
-      if (super.getEndpoint() != null) {
-        return super.getEndpoint();
-      }
-      return getDefaultEndpoint();
-    }
-
     @Override
     public StorageStubSettings build() throws IOException {
       return new StorageStubSettings(this);
diff --git a/google-cloud-storage-control/src/main/java/com/google/storage/control/v2/StorageControlClient.java b/google-cloud-storage-control/src/main/java/com/google/storage/control/v2/StorageControlClient.java
index a25fbd67e..493101034 100644
--- a/google-cloud-storage-control/src/main/java/com/google/storage/control/v2/StorageControlClient.java
+++ b/google-cloud-storage-control/src/main/java/com/google/storage/control/v2/StorageControlClient.java
@@ -70,7 +70,7 @@
  *    </tr>
  *    <tr>
  *      <td><p> CreateFolder</td>
- *      <td><p> Creates a new folder.</td>
+ *      <td><p> Creates a new folder. This operation is only applicable to a hierarchical namespace enabled bucket. Hierarchical namespace buckets are in allowlist preview.</td>
  *      <td>
  *      <p>Request object method variants only take one parameter, a request object, which must be constructed before the call.</p>
  *      <ul>
@@ -89,7 +89,7 @@
  *    </tr>
  *    <tr>
  *      <td><p> DeleteFolder</td>
- *      <td><p> Permanently deletes an empty folder.</td>
+ *      <td><p> Permanently deletes an empty folder. This operation is only applicable to a hierarchical namespace enabled bucket. Hierarchical namespace buckets are in allowlist preview.</td>
  *      <td>
  *      <p>Request object method variants only take one parameter, a request object, which must be constructed before the call.</p>
  *      <ul>
@@ -108,7 +108,7 @@
  *    </tr>
  *    <tr>
  *      <td><p> GetFolder</td>
- *      <td><p> Returns metadata for the specified folder.</td>
+ *      <td><p> Returns metadata for the specified folder. This operation is only applicable to a hierarchical namespace enabled bucket. Hierarchical namespace buckets are in allowlist preview.</td>
  *      <td>
  *      <p>Request object method variants only take one parameter, a request object, which must be constructed before the call.</p>
  *      <ul>
@@ -127,7 +127,7 @@
  *    </tr>
  *    <tr>
  *      <td><p> ListFolders</td>
- *      <td><p> Retrieves a list of folders for a given bucket.</td>
+ *      <td><p> Retrieves a list of folders. This operation is only applicable to a hierarchical namespace enabled bucket. Hierarchical namespace buckets are in allowlist preview.</td>
  *      <td>
  *      <p>Request object method variants only take one parameter, a request object, which must be constructed before the call.</p>
  *      <ul>
@@ -147,7 +147,7 @@
  *    </tr>
  *    <tr>
  *      <td><p> RenameFolder</td>
- *      <td><p> Renames a source folder to a destination folder. During a rename, the source and destination folders are locked until the long running operation completes.</td>
+ *      <td><p> Renames a source folder to a destination folder. This operation is only applicable to a hierarchical namespace enabled bucket. During a rename, the source and destination folders are locked until the long running operation completes. Hierarchical namespace buckets are in allowlist preview.</td>
  *      <td>
  *      <p>Request object method variants only take one parameter, a request object, which must be constructed before the call.</p>
  *      <ul>
@@ -365,7 +365,8 @@ public final OperationsClient getOperationsClient() {
 
   // AUTO-GENERATED DOCUMENTATION AND METHOD.
   /**
-   * Creates a new folder.
+   * Creates a new folder. This operation is only applicable to a hierarchical namespace enabled
+   * bucket. Hierarchical namespace buckets are in allowlist preview.
    *
    * <p>Sample code:
    *
@@ -383,7 +384,8 @@ public final OperationsClient getOperationsClient() {
    * }
    * }</pre>
    *
-   * @param parent Required. Name of the bucket in which the folder will reside.
+   * @param parent Required. Name of the bucket in which the folder will reside. The bucket must be
+   *     a hierarchical namespace enabled bucket.
    * @param folder Required. Properties of the new folder being created. The bucket and name of the
    *     folder are specified in the parent and folder_id fields, respectively. Populating those
    *     fields in `folder` will result in an error.
@@ -405,7 +407,8 @@ public final Folder createFolder(BucketName parent, Folder folder, String folder
 
   // AUTO-GENERATED DOCUMENTATION AND METHOD.
   /**
-   * Creates a new folder.
+   * Creates a new folder. This operation is only applicable to a hierarchical namespace enabled
+   * bucket. Hierarchical namespace buckets are in allowlist preview.
    *
    * <p>Sample code:
    *
@@ -423,7 +426,8 @@ public final Folder createFolder(BucketName parent, Folder folder, String folder
    * }
    * }</pre>
    *
-   * @param parent Required. Name of the bucket in which the folder will reside.
+   * @param parent Required. Name of the bucket in which the folder will reside. The bucket must be
+   *     a hierarchical namespace enabled bucket.
    * @param folder Required. Properties of the new folder being created. The bucket and name of the
    *     folder are specified in the parent and folder_id fields, respectively. Populating those
    *     fields in `folder` will result in an error.
@@ -445,7 +449,8 @@ public final Folder createFolder(String parent, Folder folder, String folderId)
 
   // AUTO-GENERATED DOCUMENTATION AND METHOD.
   /**
-   * Creates a new folder.
+   * Creates a new folder. This operation is only applicable to a hierarchical namespace enabled
+   * bucket. Hierarchical namespace buckets are in allowlist preview.
    *
    * <p>Sample code:
    *
@@ -477,7 +482,8 @@ public final Folder createFolder(CreateFolderRequest request) {
 
   // AUTO-GENERATED DOCUMENTATION AND METHOD.
   /**
-   * Creates a new folder.
+   * Creates a new folder. This operation is only applicable to a hierarchical namespace enabled
+   * bucket. Hierarchical namespace buckets are in allowlist preview.
    *
    * <p>Sample code:
    *
@@ -508,7 +514,8 @@ public final UnaryCallable<CreateFolderRequest, Folder> createFolderCallable() {
 
   // AUTO-GENERATED DOCUMENTATION AND METHOD.
   /**
-   * Permanently deletes an empty folder.
+   * Permanently deletes an empty folder. This operation is only applicable to a hierarchical
+   * namespace enabled bucket. Hierarchical namespace buckets are in allowlist preview.
    *
    * <p>Sample code:
    *
@@ -536,7 +543,8 @@ public final void deleteFolder(FolderName name) {
 
   // AUTO-GENERATED DOCUMENTATION AND METHOD.
   /**
-   * Permanently deletes an empty folder.
+   * Permanently deletes an empty folder. This operation is only applicable to a hierarchical
+   * namespace enabled bucket. Hierarchical namespace buckets are in allowlist preview.
    *
    * <p>Sample code:
    *
@@ -563,7 +571,8 @@ public final void deleteFolder(String name) {
 
   // AUTO-GENERATED DOCUMENTATION AND METHOD.
   /**
-   * Permanently deletes an empty folder.
+   * Permanently deletes an empty folder. This operation is only applicable to a hierarchical
+   * namespace enabled bucket. Hierarchical namespace buckets are in allowlist preview.
    *
    * <p>Sample code:
    *
@@ -594,7 +603,8 @@ public final void deleteFolder(DeleteFolderRequest request) {
 
   // AUTO-GENERATED DOCUMENTATION AND METHOD.
   /**
-   * Permanently deletes an empty folder.
+   * Permanently deletes an empty folder. This operation is only applicable to a hierarchical
+   * namespace enabled bucket. Hierarchical namespace buckets are in allowlist preview.
    *
    * <p>Sample code:
    *
@@ -624,7 +634,8 @@ public final UnaryCallable<DeleteFolderRequest, Empty> deleteFolderCallable() {
 
   // AUTO-GENERATED DOCUMENTATION AND METHOD.
   /**
-   * Returns metadata for the specified folder.
+   * Returns metadata for the specified folder. This operation is only applicable to a hierarchical
+   * namespace enabled bucket. Hierarchical namespace buckets are in allowlist preview.
    *
    * <p>Sample code:
    *
@@ -652,7 +663,8 @@ public final Folder getFolder(FolderName name) {
 
   // AUTO-GENERATED DOCUMENTATION AND METHOD.
   /**
-   * Returns metadata for the specified folder.
+   * Returns metadata for the specified folder. This operation is only applicable to a hierarchical
+   * namespace enabled bucket. Hierarchical namespace buckets are in allowlist preview.
    *
    * <p>Sample code:
    *
@@ -679,7 +691,8 @@ public final Folder getFolder(String name) {
 
   // AUTO-GENERATED DOCUMENTATION AND METHOD.
   /**
-   * Returns metadata for the specified folder.
+   * Returns metadata for the specified folder. This operation is only applicable to a hierarchical
+   * namespace enabled bucket. Hierarchical namespace buckets are in allowlist preview.
    *
    * <p>Sample code:
    *
@@ -710,7 +723,8 @@ public final Folder getFolder(GetFolderRequest request) {
 
   // AUTO-GENERATED DOCUMENTATION AND METHOD.
   /**
-   * Returns metadata for the specified folder.
+   * Returns metadata for the specified folder. This operation is only applicable to a hierarchical
+   * namespace enabled bucket. Hierarchical namespace buckets are in allowlist preview.
    *
    * <p>Sample code:
    *
@@ -740,7 +754,8 @@ public final UnaryCallable<GetFolderRequest, Folder> getFolderCallable() {
 
   // AUTO-GENERATED DOCUMENTATION AND METHOD.
   /**
-   * Retrieves a list of folders for a given bucket.
+   * Retrieves a list of folders. This operation is only applicable to a hierarchical namespace
+   * enabled bucket. Hierarchical namespace buckets are in allowlist preview.
    *
    * <p>Sample code:
    *
@@ -758,7 +773,8 @@ public final UnaryCallable<GetFolderRequest, Folder> getFolderCallable() {
    * }
    * }</pre>
    *
-   * @param parent Required. Name of the bucket in which to look for folders.
+   * @param parent Required. Name of the bucket in which to look for folders. The bucket must be a
+   *     hierarchical namespace enabled bucket.
    * @throws com.google.api.gax.rpc.ApiException if the remote call fails
    */
   public final ListFoldersPagedResponse listFolders(BucketName parent) {
@@ -771,7 +787,8 @@ public final ListFoldersPagedResponse listFolders(BucketName parent) {
 
   // AUTO-GENERATED DOCUMENTATION AND METHOD.
   /**
-   * Retrieves a list of folders for a given bucket.
+   * Retrieves a list of folders. This operation is only applicable to a hierarchical namespace
+   * enabled bucket. Hierarchical namespace buckets are in allowlist preview.
    *
    * <p>Sample code:
    *
@@ -789,7 +806,8 @@ public final ListFoldersPagedResponse listFolders(BucketName parent) {
    * }
    * }</pre>
    *
-   * @param parent Required. Name of the bucket in which to look for folders.
+   * @param parent Required. Name of the bucket in which to look for folders. The bucket must be a
+   *     hierarchical namespace enabled bucket.
    * @throws com.google.api.gax.rpc.ApiException if the remote call fails
    */
   public final ListFoldersPagedResponse listFolders(String parent) {
@@ -799,7 +817,8 @@ public final ListFoldersPagedResponse listFolders(String parent) {
 
   // AUTO-GENERATED DOCUMENTATION AND METHOD.
   /**
-   * Retrieves a list of folders for a given bucket.
+   * Retrieves a list of folders. This operation is only applicable to a hierarchical namespace
+   * enabled bucket. Hierarchical namespace buckets are in allowlist preview.
    *
    * <p>Sample code:
    *
@@ -836,7 +855,8 @@ public final ListFoldersPagedResponse listFolders(ListFoldersRequest request) {
 
   // AUTO-GENERATED DOCUMENTATION AND METHOD.
   /**
-   * Retrieves a list of folders for a given bucket.
+   * Retrieves a list of folders. This operation is only applicable to a hierarchical namespace
+   * enabled bucket. Hierarchical namespace buckets are in allowlist preview.
    *
    * <p>Sample code:
    *
@@ -874,7 +894,8 @@ public final ListFoldersPagedResponse listFolders(ListFoldersRequest request) {
 
   // AUTO-GENERATED DOCUMENTATION AND METHOD.
   /**
-   * Retrieves a list of folders for a given bucket.
+   * Retrieves a list of folders. This operation is only applicable to a hierarchical namespace
+   * enabled bucket. Hierarchical namespace buckets are in allowlist preview.
    *
    * <p>Sample code:
    *
@@ -917,8 +938,10 @@ public final UnaryCallable<ListFoldersRequest, ListFoldersResponse> listFoldersC
 
   // AUTO-GENERATED DOCUMENTATION AND METHOD.
   /**
-   * Renames a source folder to a destination folder. During a rename, the source and destination
-   * folders are locked until the long running operation completes.
+   * Renames a source folder to a destination folder. This operation is only applicable to a
+   * hierarchical namespace enabled bucket. During a rename, the source and destination folders are
+   * locked until the long running operation completes. Hierarchical namespace buckets are in
+   * allowlist preview.
    *
    * <p>Sample code:
    *
@@ -952,8 +975,10 @@ public final OperationFuture<Folder, RenameFolderMetadata> renameFolderAsync(
 
   // AUTO-GENERATED DOCUMENTATION AND METHOD.
   /**
-   * Renames a source folder to a destination folder. During a rename, the source and destination
-   * folders are locked until the long running operation completes.
+   * Renames a source folder to a destination folder. This operation is only applicable to a
+   * hierarchical namespace enabled bucket. During a rename, the source and destination folders are
+   * locked until the long running operation completes. Hierarchical namespace buckets are in
+   * allowlist preview.
    *
    * <p>Sample code:
    *
@@ -987,8 +1012,10 @@ public final OperationFuture<Folder, RenameFolderMetadata> renameFolderAsync(
 
   // AUTO-GENERATED DOCUMENTATION AND METHOD.
   /**
-   * Renames a source folder to a destination folder. During a rename, the source and destination
-   * folders are locked until the long running operation completes.
+   * Renames a source folder to a destination folder. This operation is only applicable to a
+   * hierarchical namespace enabled bucket. During a rename, the source and destination folders are
+   * locked until the long running operation completes. Hierarchical namespace buckets are in
+   * allowlist preview.
    *
    * <p>Sample code:
    *
@@ -1021,8 +1048,10 @@ public final OperationFuture<Folder, RenameFolderMetadata> renameFolderAsync(
 
   // AUTO-GENERATED DOCUMENTATION AND METHOD.
   /**
-   * Renames a source folder to a destination folder. During a rename, the source and destination
-   * folders are locked until the long running operation completes.
+   * Renames a source folder to a destination folder. This operation is only applicable to a
+   * hierarchical namespace enabled bucket. During a rename, the source and destination folders are
+   * locked until the long running operation completes. Hierarchical namespace buckets are in
+   * allowlist preview.
    *
    * <p>Sample code:
    *
@@ -1055,8 +1084,10 @@ public final OperationFuture<Folder, RenameFolderMetadata> renameFolderAsync(
 
   // AUTO-GENERATED DOCUMENTATION AND METHOD.
   /**
-   * Renames a source folder to a destination folder. During a rename, the source and destination
-   * folders are locked until the long running operation completes.
+   * Renames a source folder to a destination folder. This operation is only applicable to a
+   * hierarchical namespace enabled bucket. During a rename, the source and destination folders are
+   * locked until the long running operation completes. Hierarchical namespace buckets are in
+   * allowlist preview.
    *
    * <p>Sample code:
    *
diff --git a/google-cloud-storage-control/src/main/java/com/google/storage/control/v2/package-info.java b/google-cloud-storage-control/src/main/java/com/google/storage/control/v2/package-info.java
index 126dd95d1..4812aba87 100644
--- a/google-cloud-storage-control/src/main/java/com/google/storage/control/v2/package-info.java
+++ b/google-cloud-storage-control/src/main/java/com/google/storage/control/v2/package-info.java
@@ -15,7 +15,7 @@
  */
 
 /**
- * A client to Cloud Storage API
+ * A client to Storage Control API
  *
  * <p>The interfaces provided are listed below, along with usage samples.
  *
diff --git a/google-cloud-storage-control/src/main/java/com/google/storage/control/v2/stub/StorageControlStubSettings.java b/google-cloud-storage-control/src/main/java/com/google/storage/control/v2/stub/StorageControlStubSettings.java
index 5b34d7005..eb717d382 100644
--- a/google-cloud-storage-control/src/main/java/com/google/storage/control/v2/stub/StorageControlStubSettings.java
+++ b/google-cloud-storage-control/src/main/java/com/google/storage/control/v2/stub/StorageControlStubSettings.java
@@ -322,15 +322,6 @@ public StorageControlStub createStub() throws IOException {
             "Transport not supported: %s", getTransportChannelProvider().getTransportName()));
   }
 
-  /** Returns the endpoint set by the user or the the service's default endpoint. */
-  @Override
-  public String getEndpoint() {
-    if (super.getEndpoint() != null) {
-      return super.getEndpoint();
-    }
-    return getDefaultEndpoint();
-  }
-
   /** Returns the default service name. */
   @Override
   public String getServiceName() {
@@ -715,15 +706,6 @@ public UnaryCallSettings.Builder<RenameFolderRequest, Operation> renameFolderSet
       return listManagedFoldersSettings;
     }
 
-    /** Returns the endpoint set by the user or the the service's default endpoint. */
-    @Override
-    public String getEndpoint() {
-      if (super.getEndpoint() != null) {
-        return super.getEndpoint();
-      }
-      return getDefaultEndpoint();
-    }
-
     @Override
     public StorageControlStubSettings build() throws IOException {
       return new StorageControlStubSettings(this);
diff --git a/grpc-google-cloud-storage-control-v2/src/main/java/com/google/storage/control/v2/StorageControlGrpc.java b/grpc-google-cloud-storage-control-v2/src/main/java/com/google/storage/control/v2/StorageControlGrpc.java
index 476945a17..9456b8171 100644
--- a/grpc-google-cloud-storage-control-v2/src/main/java/com/google/storage/control/v2/StorageControlGrpc.java
+++ b/grpc-google-cloud-storage-control-v2/src/main/java/com/google/storage/control/v2/StorageControlGrpc.java
@@ -539,7 +539,9 @@ public interface AsyncService {
      *
      *
      * <pre>
-     * Creates a new folder.
+     * Creates a new folder. This operation is only applicable to a hierarchical
+     * namespace enabled bucket.
+     * Hierarchical namespace buckets are in allowlist preview.
      * </pre>
      */
     default void createFolder(
@@ -553,7 +555,9 @@ default void createFolder(
      *
      *
      * <pre>
-     * Permanently deletes an empty folder.
+     * Permanently deletes an empty folder. This operation is only applicable to a
+     * hierarchical namespace enabled bucket.
+     * Hierarchical namespace buckets are in allowlist preview.
      * </pre>
      */
     default void deleteFolder(
@@ -567,7 +571,9 @@ default void deleteFolder(
      *
      *
      * <pre>
-     * Returns metadata for the specified folder.
+     * Returns metadata for the specified folder. This operation is only
+     * applicable to a hierarchical namespace enabled bucket.
+     * Hierarchical namespace buckets are in allowlist preview.
      * </pre>
      */
     default void getFolder(
@@ -580,7 +586,9 @@ default void getFolder(
      *
      *
      * <pre>
-     * Retrieves a list of folders for a given bucket.
+     * Retrieves a list of folders. This operation is only applicable to a
+     * hierarchical namespace enabled bucket.
+     * Hierarchical namespace buckets are in allowlist preview.
      * </pre>
      */
     default void listFolders(
@@ -595,9 +603,11 @@ default void listFolders(
      *
      *
      * <pre>
-     * Renames a source folder to a destination folder. During a rename, the
+     * Renames a source folder to a destination folder. This operation is only
+     * applicable to a hierarchical namespace enabled bucket. During a rename, the
      * source and destination folders are locked until the long running operation
      * completes.
+     * Hierarchical namespace buckets are in allowlist preview.
      * </pre>
      */
     default void renameFolder(
@@ -717,7 +727,9 @@ protected StorageControlStub build(io.grpc.Channel channel, io.grpc.CallOptions
      *
      *
      * <pre>
-     * Creates a new folder.
+     * Creates a new folder. This operation is only applicable to a hierarchical
+     * namespace enabled bucket.
+     * Hierarchical namespace buckets are in allowlist preview.
      * </pre>
      */
     public void createFolder(
@@ -733,7 +745,9 @@ public void createFolder(
      *
      *
      * <pre>
-     * Permanently deletes an empty folder.
+     * Permanently deletes an empty folder. This operation is only applicable to a
+     * hierarchical namespace enabled bucket.
+     * Hierarchical namespace buckets are in allowlist preview.
      * </pre>
      */
     public void deleteFolder(
@@ -749,7 +763,9 @@ public void deleteFolder(
      *
      *
      * <pre>
-     * Returns metadata for the specified folder.
+     * Returns metadata for the specified folder. This operation is only
+     * applicable to a hierarchical namespace enabled bucket.
+     * Hierarchical namespace buckets are in allowlist preview.
      * </pre>
      */
     public void getFolder(
@@ -763,7 +779,9 @@ public void getFolder(
      *
      *
      * <pre>
-     * Retrieves a list of folders for a given bucket.
+     * Retrieves a list of folders. This operation is only applicable to a
+     * hierarchical namespace enabled bucket.
+     * Hierarchical namespace buckets are in allowlist preview.
      * </pre>
      */
     public void listFolders(
@@ -780,9 +798,11 @@ public void listFolders(
      *
      *
      * <pre>
-     * Renames a source folder to a destination folder. During a rename, the
+     * Renames a source folder to a destination folder. This operation is only
+     * applicable to a hierarchical namespace enabled bucket. During a rename, the
      * source and destination folders are locked until the long running operation
      * completes.
+     * Hierarchical namespace buckets are in allowlist preview.
      * </pre>
      */
     public void renameFolder(
@@ -899,7 +919,9 @@ protected StorageControlBlockingStub build(
      *
      *
      * <pre>
-     * Creates a new folder.
+     * Creates a new folder. This operation is only applicable to a hierarchical
+     * namespace enabled bucket.
+     * Hierarchical namespace buckets are in allowlist preview.
      * </pre>
      */
     public com.google.storage.control.v2.Folder createFolder(
@@ -912,7 +934,9 @@ public com.google.storage.control.v2.Folder createFolder(
      *
      *
      * <pre>
-     * Permanently deletes an empty folder.
+     * Permanently deletes an empty folder. This operation is only applicable to a
+     * hierarchical namespace enabled bucket.
+     * Hierarchical namespace buckets are in allowlist preview.
      * </pre>
      */
     public com.google.protobuf.Empty deleteFolder(
@@ -925,7 +949,9 @@ public com.google.protobuf.Empty deleteFolder(
      *
      *
      * <pre>
-     * Returns metadata for the specified folder.
+     * Returns metadata for the specified folder. This operation is only
+     * applicable to a hierarchical namespace enabled bucket.
+     * Hierarchical namespace buckets are in allowlist preview.
      * </pre>
      */
     public com.google.storage.control.v2.Folder getFolder(
@@ -938,7 +964,9 @@ public com.google.storage.control.v2.Folder getFolder(
      *
      *
      * <pre>
-     * Retrieves a list of folders for a given bucket.
+     * Retrieves a list of folders. This operation is only applicable to a
+     * hierarchical namespace enabled bucket.
+     * Hierarchical namespace buckets are in allowlist preview.
      * </pre>
      */
     public com.google.storage.control.v2.ListFoldersResponse listFolders(
@@ -951,9 +979,11 @@ public com.google.storage.control.v2.ListFoldersResponse listFolders(
      *
      *
      * <pre>
-     * Renames a source folder to a destination folder. During a rename, the
+     * Renames a source folder to a destination folder. This operation is only
+     * applicable to a hierarchical namespace enabled bucket. During a rename, the
      * source and destination folders are locked until the long running operation
      * completes.
+     * Hierarchical namespace buckets are in allowlist preview.
      * </pre>
      */
     public com.google.longrunning.Operation renameFolder(
@@ -1051,7 +1081,9 @@ protected StorageControlFutureStub build(
      *
      *
      * <pre>
-     * Creates a new folder.
+     * Creates a new folder. This operation is only applicable to a hierarchical
+     * namespace enabled bucket.
+     * Hierarchical namespace buckets are in allowlist preview.
      * </pre>
      */
     public com.google.common.util.concurrent.ListenableFuture<com.google.storage.control.v2.Folder>
@@ -1064,7 +1096,9 @@ protected StorageControlFutureStub build(
      *
      *
      * <pre>
-     * Permanently deletes an empty folder.
+     * Permanently deletes an empty folder. This operation is only applicable to a
+     * hierarchical namespace enabled bucket.
+     * Hierarchical namespace buckets are in allowlist preview.
      * </pre>
      */
     public com.google.common.util.concurrent.ListenableFuture<com.google.protobuf.Empty>
@@ -1077,7 +1111,9 @@ protected StorageControlFutureStub build(
      *
      *
      * <pre>
-     * Returns metadata for the specified folder.
+     * Returns metadata for the specified folder. This operation is only
+     * applicable to a hierarchical namespace enabled bucket.
+     * Hierarchical namespace buckets are in allowlist preview.
      * </pre>
      */
     public com.google.common.util.concurrent.ListenableFuture<com.google.storage.control.v2.Folder>
@@ -1090,7 +1126,9 @@ protected StorageControlFutureStub build(
      *
      *
      * <pre>
-     * Retrieves a list of folders for a given bucket.
+     * Retrieves a list of folders. This operation is only applicable to a
+     * hierarchical namespace enabled bucket.
+     * Hierarchical namespace buckets are in allowlist preview.
      * </pre>
      */
     public com.google.common.util.concurrent.ListenableFuture<
@@ -1104,9 +1142,11 @@ protected StorageControlFutureStub build(
      *
      *
      * <pre>
-     * Renames a source folder to a destination folder. During a rename, the
+     * Renames a source folder to a destination folder. This operation is only
+     * applicable to a hierarchical namespace enabled bucket. During a rename, the
      * source and destination folders are locked until the long running operation
      * completes.
+     * Hierarchical namespace buckets are in allowlist preview.
      * </pre>
      */
     public com.google.common.util.concurrent.ListenableFuture<com.google.longrunning.Operation>
diff --git a/proto-google-cloud-storage-control-v2/src/main/java/com/google/storage/control/v2/CreateFolderRequest.java b/proto-google-cloud-storage-control-v2/src/main/java/com/google/storage/control/v2/CreateFolderRequest.java
index 9fe4ed2e7..0686e2ed6 100644
--- a/proto-google-cloud-storage-control-v2/src/main/java/com/google/storage/control/v2/CreateFolderRequest.java
+++ b/proto-google-cloud-storage-control-v2/src/main/java/com/google/storage/control/v2/CreateFolderRequest.java
@@ -23,7 +23,9 @@
  *
  *
  * <pre>
- * Request message for CreateFolder.
+ * Request message for CreateFolder. This operation is only applicable to a
+ * hierarchical namespace enabled bucket.
+ * Hierarchical namespace buckets are in allowlist preview.
  * </pre>
  *
  * Protobuf type {@code google.storage.control.v2.CreateFolderRequest}
@@ -74,7 +76,8 @@ public static final com.google.protobuf.Descriptors.Descriptor getDescriptor() {
    *
    *
    * <pre>
-   * Required. Name of the bucket in which the folder will reside.
+   * Required. Name of the bucket in which the folder will reside. The bucket
+   * must be a hierarchical namespace enabled bucket.
    * </pre>
    *
    * <code>
@@ -99,7 +102,8 @@ public java.lang.String getParent() {
    *
    *
    * <pre>
-   * Required. Name of the bucket in which the folder will reside.
+   * Required. Name of the bucket in which the folder will reside. The bucket
+   * must be a hierarchical namespace enabled bucket.
    * </pre>
    *
    * <code>
@@ -266,8 +270,7 @@ public boolean getRecursive() {
    *
    * <pre>
    * Optional. A unique identifier for this request. UUID is the recommended
-   * format, but other formats are still accepted. This request is only
-   * idempotent if a `request_id` is provided.
+   * format, but other formats are still accepted.
    * </pre>
    *
    * <code>
@@ -293,8 +296,7 @@ public java.lang.String getRequestId() {
    *
    * <pre>
    * Optional. A unique identifier for this request. UUID is the recommended
-   * format, but other formats are still accepted. This request is only
-   * idempotent if a `request_id` is provided.
+   * format, but other formats are still accepted.
    * </pre>
    *
    * <code>
@@ -520,7 +522,9 @@ protected Builder newBuilderForType(com.google.protobuf.GeneratedMessageV3.Build
    *
    *
    * <pre>
-   * Request message for CreateFolder.
+   * Request message for CreateFolder. This operation is only applicable to a
+   * hierarchical namespace enabled bucket.
+   * Hierarchical namespace buckets are in allowlist preview.
    * </pre>
    *
    * Protobuf type {@code google.storage.control.v2.CreateFolderRequest}
@@ -776,7 +780,8 @@ public Builder mergeFrom(
      *
      *
      * <pre>
-     * Required. Name of the bucket in which the folder will reside.
+     * Required. Name of the bucket in which the folder will reside. The bucket
+     * must be a hierarchical namespace enabled bucket.
      * </pre>
      *
      * <code>
@@ -800,7 +805,8 @@ public java.lang.String getParent() {
      *
      *
      * <pre>
-     * Required. Name of the bucket in which the folder will reside.
+     * Required. Name of the bucket in which the folder will reside. The bucket
+     * must be a hierarchical namespace enabled bucket.
      * </pre>
      *
      * <code>
@@ -824,7 +830,8 @@ public com.google.protobuf.ByteString getParentBytes() {
      *
      *
      * <pre>
-     * Required. Name of the bucket in which the folder will reside.
+     * Required. Name of the bucket in which the folder will reside. The bucket
+     * must be a hierarchical namespace enabled bucket.
      * </pre>
      *
      * <code>
@@ -847,7 +854,8 @@ public Builder setParent(java.lang.String value) {
      *
      *
      * <pre>
-     * Required. Name of the bucket in which the folder will reside.
+     * Required. Name of the bucket in which the folder will reside. The bucket
+     * must be a hierarchical namespace enabled bucket.
      * </pre>
      *
      * <code>
@@ -866,7 +874,8 @@ public Builder clearParent() {
      *
      *
      * <pre>
-     * Required. Name of the bucket in which the folder will reside.
+     * Required. Name of the bucket in which the folder will reside. The bucket
+     * must be a hierarchical namespace enabled bucket.
      * </pre>
      *
      * <code>
@@ -1296,8 +1305,7 @@ public Builder clearRecursive() {
      *
      * <pre>
      * Optional. A unique identifier for this request. UUID is the recommended
-     * format, but other formats are still accepted. This request is only
-     * idempotent if a `request_id` is provided.
+     * format, but other formats are still accepted.
      * </pre>
      *
      * <code>
@@ -1322,8 +1330,7 @@ public java.lang.String getRequestId() {
      *
      * <pre>
      * Optional. A unique identifier for this request. UUID is the recommended
-     * format, but other formats are still accepted. This request is only
-     * idempotent if a `request_id` is provided.
+     * format, but other formats are still accepted.
      * </pre>
      *
      * <code>
@@ -1348,8 +1355,7 @@ public com.google.protobuf.ByteString getRequestIdBytes() {
      *
      * <pre>
      * Optional. A unique identifier for this request. UUID is the recommended
-     * format, but other formats are still accepted. This request is only
-     * idempotent if a `request_id` is provided.
+     * format, but other formats are still accepted.
      * </pre>
      *
      * <code>
@@ -1373,8 +1379,7 @@ public Builder setRequestId(java.lang.String value) {
      *
      * <pre>
      * Optional. A unique identifier for this request. UUID is the recommended
-     * format, but other formats are still accepted. This request is only
-     * idempotent if a `request_id` is provided.
+     * format, but other formats are still accepted.
      * </pre>
      *
      * <code>
@@ -1394,8 +1399,7 @@ public Builder clearRequestId() {
      *
      * <pre>
      * Optional. A unique identifier for this request. UUID is the recommended
-     * format, but other formats are still accepted. This request is only
-     * idempotent if a `request_id` is provided.
+     * format, but other formats are still accepted.
      * </pre>
      *
      * <code>
diff --git a/proto-google-cloud-storage-control-v2/src/main/java/com/google/storage/control/v2/CreateFolderRequestOrBuilder.java b/proto-google-cloud-storage-control-v2/src/main/java/com/google/storage/control/v2/CreateFolderRequestOrBuilder.java
index 38b0041b5..88c7f84c5 100644
--- a/proto-google-cloud-storage-control-v2/src/main/java/com/google/storage/control/v2/CreateFolderRequestOrBuilder.java
+++ b/proto-google-cloud-storage-control-v2/src/main/java/com/google/storage/control/v2/CreateFolderRequestOrBuilder.java
@@ -28,7 +28,8 @@ public interface CreateFolderRequestOrBuilder
    *
    *
    * <pre>
-   * Required. Name of the bucket in which the folder will reside.
+   * Required. Name of the bucket in which the folder will reside. The bucket
+   * must be a hierarchical namespace enabled bucket.
    * </pre>
    *
    * <code>
@@ -42,7 +43,8 @@ public interface CreateFolderRequestOrBuilder
    *
    *
    * <pre>
-   * Required. Name of the bucket in which the folder will reside.
+   * Required. Name of the bucket in which the folder will reside. The bucket
+   * must be a hierarchical namespace enabled bucket.
    * </pre>
    *
    * <code>
@@ -152,8 +154,7 @@ public interface CreateFolderRequestOrBuilder
    *
    * <pre>
    * Optional. A unique identifier for this request. UUID is the recommended
-   * format, but other formats are still accepted. This request is only
-   * idempotent if a `request_id` is provided.
+   * format, but other formats are still accepted.
    * </pre>
    *
    * <code>
@@ -168,8 +169,7 @@ public interface CreateFolderRequestOrBuilder
    *
    * <pre>
    * Optional. A unique identifier for this request. UUID is the recommended
-   * format, but other formats are still accepted. This request is only
-   * idempotent if a `request_id` is provided.
+   * format, but other formats are still accepted.
    * </pre>
    *
    * <code>
diff --git a/proto-google-cloud-storage-control-v2/src/main/java/com/google/storage/control/v2/DeleteFolderRequest.java b/proto-google-cloud-storage-control-v2/src/main/java/com/google/storage/control/v2/DeleteFolderRequest.java
index 5c7021027..8c53dc04f 100644
--- a/proto-google-cloud-storage-control-v2/src/main/java/com/google/storage/control/v2/DeleteFolderRequest.java
+++ b/proto-google-cloud-storage-control-v2/src/main/java/com/google/storage/control/v2/DeleteFolderRequest.java
@@ -23,7 +23,9 @@
  *
  *
  * <pre>
- * Request message for DeleteFolder.
+ * Request message for DeleteFolder. This operation is only applicable to a
+ * hierarchical namespace enabled bucket.
+ * Hierarchical namespace buckets are in allowlist preview.
  * </pre>
  *
  * Protobuf type {@code google.storage.control.v2.DeleteFolderRequest}
@@ -201,8 +203,7 @@ public long getIfMetagenerationNotMatch() {
    *
    * <pre>
    * Optional. A unique identifier for this request. UUID is the recommended
-   * format, but other formats are still accepted. This request is only
-   * idempotent if a `request_id` is provided.
+   * format, but other formats are still accepted.
    * </pre>
    *
    * <code>
@@ -228,8 +229,7 @@ public java.lang.String getRequestId() {
    *
    * <pre>
    * Optional. A unique identifier for this request. UUID is the recommended
-   * format, but other formats are still accepted. This request is only
-   * idempotent if a `request_id` is provided.
+   * format, but other formats are still accepted.
    * </pre>
    *
    * <code>
@@ -451,7 +451,9 @@ protected Builder newBuilderForType(com.google.protobuf.GeneratedMessageV3.Build
    *
    *
    * <pre>
-   * Request message for DeleteFolder.
+   * Request message for DeleteFolder. This operation is only applicable to a
+   * hierarchical namespace enabled bucket.
+   * Hierarchical namespace buckets are in allowlist preview.
    * </pre>
    *
    * Protobuf type {@code google.storage.control.v2.DeleteFolderRequest}
@@ -946,8 +948,7 @@ public Builder clearIfMetagenerationNotMatch() {
      *
      * <pre>
      * Optional. A unique identifier for this request. UUID is the recommended
-     * format, but other formats are still accepted. This request is only
-     * idempotent if a `request_id` is provided.
+     * format, but other formats are still accepted.
      * </pre>
      *
      * <code>
@@ -972,8 +973,7 @@ public java.lang.String getRequestId() {
      *
      * <pre>
      * Optional. A unique identifier for this request. UUID is the recommended
-     * format, but other formats are still accepted. This request is only
-     * idempotent if a `request_id` is provided.
+     * format, but other formats are still accepted.
      * </pre>
      *
      * <code>
@@ -998,8 +998,7 @@ public com.google.protobuf.ByteString getRequestIdBytes() {
      *
      * <pre>
      * Optional. A unique identifier for this request. UUID is the recommended
-     * format, but other formats are still accepted. This request is only
-     * idempotent if a `request_id` is provided.
+     * format, but other formats are still accepted.
      * </pre>
      *
      * <code>
@@ -1023,8 +1022,7 @@ public Builder setRequestId(java.lang.String value) {
      *
      * <pre>
      * Optional. A unique identifier for this request. UUID is the recommended
-     * format, but other formats are still accepted. This request is only
-     * idempotent if a `request_id` is provided.
+     * format, but other formats are still accepted.
      * </pre>
      *
      * <code>
@@ -1044,8 +1042,7 @@ public Builder clearRequestId() {
      *
      * <pre>
      * Optional. A unique identifier for this request. UUID is the recommended
-     * format, but other formats are still accepted. This request is only
-     * idempotent if a `request_id` is provided.
+     * format, but other formats are still accepted.
      * </pre>
      *
      * <code>
diff --git a/proto-google-cloud-storage-control-v2/src/main/java/com/google/storage/control/v2/DeleteFolderRequestOrBuilder.java b/proto-google-cloud-storage-control-v2/src/main/java/com/google/storage/control/v2/DeleteFolderRequestOrBuilder.java
index 2e7004fde..3f7b5b622 100644
--- a/proto-google-cloud-storage-control-v2/src/main/java/com/google/storage/control/v2/DeleteFolderRequestOrBuilder.java
+++ b/proto-google-cloud-storage-control-v2/src/main/java/com/google/storage/control/v2/DeleteFolderRequestOrBuilder.java
@@ -114,8 +114,7 @@ public interface DeleteFolderRequestOrBuilder
    *
    * <pre>
    * Optional. A unique identifier for this request. UUID is the recommended
-   * format, but other formats are still accepted. This request is only
-   * idempotent if a `request_id` is provided.
+   * format, but other formats are still accepted.
    * </pre>
    *
    * <code>
@@ -130,8 +129,7 @@ public interface DeleteFolderRequestOrBuilder
    *
    * <pre>
    * Optional. A unique identifier for this request. UUID is the recommended
-   * format, but other formats are still accepted. This request is only
-   * idempotent if a `request_id` is provided.
+   * format, but other formats are still accepted.
    * </pre>
    *
    * <code>
diff --git a/proto-google-cloud-storage-control-v2/src/main/java/com/google/storage/control/v2/Folder.java b/proto-google-cloud-storage-control-v2/src/main/java/com/google/storage/control/v2/Folder.java
index c05fc4574..5a4ec2f54 100644
--- a/proto-google-cloud-storage-control-v2/src/main/java/com/google/storage/control/v2/Folder.java
+++ b/proto-google-cloud-storage-control-v2/src/main/java/com/google/storage/control/v2/Folder.java
@@ -23,7 +23,9 @@
  *
  *
  * <pre>
- * A folder.
+ * A folder resource. This resource can only exist in a hierarchical namespace
+ * enabled bucket.
+ * Hierarchical namespace buckets are in allowlist preview.
  * </pre>
  *
  * Protobuf type {@code google.storage.control.v2.Folder}
@@ -514,7 +516,9 @@ protected Builder newBuilderForType(com.google.protobuf.GeneratedMessageV3.Build
    *
    *
    * <pre>
-   * A folder.
+   * A folder resource. This resource can only exist in a hierarchical namespace
+   * enabled bucket.
+   * Hierarchical namespace buckets are in allowlist preview.
    * </pre>
    *
    * Protobuf type {@code google.storage.control.v2.Folder}
diff --git a/proto-google-cloud-storage-control-v2/src/main/java/com/google/storage/control/v2/GetFolderRequest.java b/proto-google-cloud-storage-control-v2/src/main/java/com/google/storage/control/v2/GetFolderRequest.java
index abaa8c2ab..6baf949a6 100644
--- a/proto-google-cloud-storage-control-v2/src/main/java/com/google/storage/control/v2/GetFolderRequest.java
+++ b/proto-google-cloud-storage-control-v2/src/main/java/com/google/storage/control/v2/GetFolderRequest.java
@@ -23,7 +23,9 @@
  *
  *
  * <pre>
- * Request message for GetFolder.
+ * Request message for GetFolder. This operation is only applicable to a
+ * hierarchical namespace enabled bucket.
+ * Hierarchical namespace buckets are in allowlist preview.
  * </pre>
  *
  * Protobuf type {@code google.storage.control.v2.GetFolderRequest}
@@ -449,7 +451,9 @@ protected Builder newBuilderForType(com.google.protobuf.GeneratedMessageV3.Build
    *
    *
    * <pre>
-   * Request message for GetFolder.
+   * Request message for GetFolder. This operation is only applicable to a
+   * hierarchical namespace enabled bucket.
+   * Hierarchical namespace buckets are in allowlist preview.
    * </pre>
    *
    * Protobuf type {@code google.storage.control.v2.GetFolderRequest}
diff --git a/proto-google-cloud-storage-control-v2/src/main/java/com/google/storage/control/v2/ListFoldersRequest.java b/proto-google-cloud-storage-control-v2/src/main/java/com/google/storage/control/v2/ListFoldersRequest.java
index 0d8481b80..e47352baf 100644
--- a/proto-google-cloud-storage-control-v2/src/main/java/com/google/storage/control/v2/ListFoldersRequest.java
+++ b/proto-google-cloud-storage-control-v2/src/main/java/com/google/storage/control/v2/ListFoldersRequest.java
@@ -23,7 +23,9 @@
  *
  *
  * <pre>
- * Request message for ListFolders.
+ * Request message for ListFolders. This operation is only applicable to a
+ * hierarchical namespace enabled bucket.
+ * Hierarchical namespace buckets are in allowlist preview.
  * </pre>
  *
  * Protobuf type {@code google.storage.control.v2.ListFoldersRequest}
@@ -77,7 +79,8 @@ public static final com.google.protobuf.Descriptors.Descriptor getDescriptor() {
    *
    *
    * <pre>
-   * Required. Name of the bucket in which to look for folders.
+   * Required. Name of the bucket in which to look for folders. The bucket must
+   * be a hierarchical namespace enabled bucket.
    * </pre>
    *
    * <code>
@@ -102,7 +105,8 @@ public java.lang.String getParent() {
    *
    *
    * <pre>
-   * Required. Name of the bucket in which to look for folders.
+   * Required. Name of the bucket in which to look for folders. The bucket must
+   * be a hierarchical namespace enabled bucket.
    * </pre>
    *
    * <code>
@@ -701,7 +705,9 @@ protected Builder newBuilderForType(com.google.protobuf.GeneratedMessageV3.Build
    *
    *
    * <pre>
-   * Request message for ListFolders.
+   * Request message for ListFolders. This operation is only applicable to a
+   * hierarchical namespace enabled bucket.
+   * Hierarchical namespace buckets are in allowlist preview.
    * </pre>
    *
    * Protobuf type {@code google.storage.control.v2.ListFoldersRequest}
@@ -988,7 +994,8 @@ public Builder mergeFrom(
      *
      *
      * <pre>
-     * Required. Name of the bucket in which to look for folders.
+     * Required. Name of the bucket in which to look for folders. The bucket must
+     * be a hierarchical namespace enabled bucket.
      * </pre>
      *
      * <code>
@@ -1012,7 +1019,8 @@ public java.lang.String getParent() {
      *
      *
      * <pre>
-     * Required. Name of the bucket in which to look for folders.
+     * Required. Name of the bucket in which to look for folders. The bucket must
+     * be a hierarchical namespace enabled bucket.
      * </pre>
      *
      * <code>
@@ -1036,7 +1044,8 @@ public com.google.protobuf.ByteString getParentBytes() {
      *
      *
      * <pre>
-     * Required. Name of the bucket in which to look for folders.
+     * Required. Name of the bucket in which to look for folders. The bucket must
+     * be a hierarchical namespace enabled bucket.
      * </pre>
      *
      * <code>
@@ -1059,7 +1068,8 @@ public Builder setParent(java.lang.String value) {
      *
      *
      * <pre>
-     * Required. Name of the bucket in which to look for folders.
+     * Required. Name of the bucket in which to look for folders. The bucket must
+     * be a hierarchical namespace enabled bucket.
      * </pre>
      *
      * <code>
@@ -1078,7 +1088,8 @@ public Builder clearParent() {
      *
      *
      * <pre>
-     * Required. Name of the bucket in which to look for folders.
+     * Required. Name of the bucket in which to look for folders. The bucket must
+     * be a hierarchical namespace enabled bucket.
      * </pre>
      *
      * <code>
diff --git a/proto-google-cloud-storage-control-v2/src/main/java/com/google/storage/control/v2/ListFoldersRequestOrBuilder.java b/proto-google-cloud-storage-control-v2/src/main/java/com/google/storage/control/v2/ListFoldersRequestOrBuilder.java
index 113d2ff3e..0e06b4323 100644
--- a/proto-google-cloud-storage-control-v2/src/main/java/com/google/storage/control/v2/ListFoldersRequestOrBuilder.java
+++ b/proto-google-cloud-storage-control-v2/src/main/java/com/google/storage/control/v2/ListFoldersRequestOrBuilder.java
@@ -28,7 +28,8 @@ public interface ListFoldersRequestOrBuilder
    *
    *
    * <pre>
-   * Required. Name of the bucket in which to look for folders.
+   * Required. Name of the bucket in which to look for folders. The bucket must
+   * be a hierarchical namespace enabled bucket.
    * </pre>
    *
    * <code>
@@ -42,7 +43,8 @@ public interface ListFoldersRequestOrBuilder
    *
    *
    * <pre>
-   * Required. Name of the bucket in which to look for folders.
+   * Required. Name of the bucket in which to look for folders. The bucket must
+   * be a hierarchical namespace enabled bucket.
    * </pre>
    *
    * <code>
diff --git a/proto-google-cloud-storage-control-v2/src/main/java/com/google/storage/control/v2/RenameFolderRequest.java b/proto-google-cloud-storage-control-v2/src/main/java/com/google/storage/control/v2/RenameFolderRequest.java
index 46a2ba440..aed982fd2 100644
--- a/proto-google-cloud-storage-control-v2/src/main/java/com/google/storage/control/v2/RenameFolderRequest.java
+++ b/proto-google-cloud-storage-control-v2/src/main/java/com/google/storage/control/v2/RenameFolderRequest.java
@@ -23,7 +23,9 @@
  *
  *
  * <pre>
- * Request message for RenameFolder.
+ * Request message for RenameFolder. This operation is only applicable to a
+ * hierarchical namespace enabled bucket.
+ * Hierarchical namespace buckets are in allowlist preview.
  * </pre>
  *
  * Protobuf type {@code google.storage.control.v2.RenameFolderRequest}
@@ -512,7 +514,9 @@ protected Builder newBuilderForType(com.google.protobuf.GeneratedMessageV3.Build
    *
    *
    * <pre>
-   * Request message for RenameFolder.
+   * Request message for RenameFolder. This operation is only applicable to a
+   * hierarchical namespace enabled bucket.
+   * Hierarchical namespace buckets are in allowlist preview.
    * </pre>
    *
    * Protobuf type {@code google.storage.control.v2.RenameFolderRequest}
diff --git a/proto-google-cloud-storage-control-v2/src/main/proto/google/storage/control/v2/storage_control.proto b/proto-google-cloud-storage-control-v2/src/main/proto/google/storage/control/v2/storage_control.proto
index 5e460eb9c..61663a646 100644
--- a/proto-google-cloud-storage-control-v2/src/main/proto/google/storage/control/v2/storage_control.proto
+++ b/proto-google-cloud-storage-control-v2/src/main/proto/google/storage/control/v2/storage_control.proto
@@ -47,7 +47,9 @@ service StorageControl {
       "https://www.googleapis.com/auth/devstorage.read_only,"
       "https://www.googleapis.com/auth/devstorage.read_write";
 
-  // Creates a new folder.
+  // Creates a new folder. This operation is only applicable to a hierarchical
+  // namespace enabled bucket.
+  // Hierarchical namespace buckets are in allowlist preview.
   rpc CreateFolder(CreateFolderRequest) returns (Folder) {
     option (google.api.routing) = {
       routing_parameters { field: "parent" path_template: "{bucket=**}" }
@@ -55,7 +57,9 @@ service StorageControl {
     option (google.api.method_signature) = "parent,folder,folder_id";
   }
 
-  // Permanently deletes an empty folder.
+  // Permanently deletes an empty folder. This operation is only applicable to a
+  // hierarchical namespace enabled bucket.
+  // Hierarchical namespace buckets are in allowlist preview.
   rpc DeleteFolder(DeleteFolderRequest) returns (google.protobuf.Empty) {
     option (google.api.routing) = {
       routing_parameters {
@@ -66,7 +70,9 @@ service StorageControl {
     option (google.api.method_signature) = "name";
   }
 
-  // Returns metadata for the specified folder.
+  // Returns metadata for the specified folder. This operation is only
+  // applicable to a hierarchical namespace enabled bucket.
+  // Hierarchical namespace buckets are in allowlist preview.
   rpc GetFolder(GetFolderRequest) returns (Folder) {
     option (google.api.routing) = {
       routing_parameters {
@@ -77,7 +83,9 @@ service StorageControl {
     option (google.api.method_signature) = "name";
   }
 
-  // Retrieves a list of folders for a given bucket.
+  // Retrieves a list of folders. This operation is only applicable to a
+  // hierarchical namespace enabled bucket.
+  // Hierarchical namespace buckets are in allowlist preview.
   rpc ListFolders(ListFoldersRequest) returns (ListFoldersResponse) {
     option (google.api.routing) = {
       routing_parameters { field: "parent" path_template: "{bucket=**}" }
@@ -85,9 +93,11 @@ service StorageControl {
     option (google.api.method_signature) = "parent";
   }
 
-  // Renames a source folder to a destination folder. During a rename, the
+  // Renames a source folder to a destination folder. This operation is only
+  // applicable to a hierarchical namespace enabled bucket. During a rename, the
   // source and destination folders are locked until the long running operation
   // completes.
+  // Hierarchical namespace buckets are in allowlist preview.
   rpc RenameFolder(RenameFolderRequest) returns (google.longrunning.Operation) {
     option (google.api.routing) = {
       routing_parameters {
@@ -161,7 +171,9 @@ message PendingRenameInfo {
   string operation = 1 [(google.api.field_behavior) = OUTPUT_ONLY];
 }
 
-// A folder.
+// A folder resource. This resource can only exist in a hierarchical namespace
+// enabled bucket.
+// Hierarchical namespace buckets are in allowlist preview.
 message Folder {
   option (google.api.resource) = {
     type: "storage.googleapis.com/Folder"
@@ -195,7 +207,9 @@ message Folder {
       [(google.api.field_behavior) = OUTPUT_ONLY];
 }
 
-// Request message for GetFolder.
+// Request message for GetFolder. This operation is only applicable to a
+// hierarchical namespace enabled bucket.
+// Hierarchical namespace buckets are in allowlist preview.
 message GetFolderRequest {
   // Required. Name of the folder.
   // Format: `projects/{project}/buckets/{bucket}/folders/{folder}`
@@ -220,9 +234,12 @@ message GetFolderRequest {
   ];
 }
 
-// Request message for CreateFolder.
+// Request message for CreateFolder. This operation is only applicable to a
+// hierarchical namespace enabled bucket.
+// Hierarchical namespace buckets are in allowlist preview.
 message CreateFolderRequest {
-  // Required. Name of the bucket in which the folder will reside.
+  // Required. Name of the bucket in which the folder will reside. The bucket
+  // must be a hierarchical namespace enabled bucket.
   string parent = 1 [
     (google.api.field_behavior) = REQUIRED,
     (google.api.resource_reference) = {
@@ -248,15 +265,16 @@ message CreateFolderRequest {
   bool recursive = 4 [(google.api.field_behavior) = OPTIONAL];
 
   // Optional. A unique identifier for this request. UUID is the recommended
-  // format, but other formats are still accepted. This request is only
-  // idempotent if a `request_id` is provided.
+  // format, but other formats are still accepted.
   string request_id = 5 [
     (google.api.field_info).format = UUID4,
     (google.api.field_behavior) = OPTIONAL
   ];
 }
 
-// Request message for DeleteFolder.
+// Request message for DeleteFolder. This operation is only applicable to a
+// hierarchical namespace enabled bucket.
+// Hierarchical namespace buckets are in allowlist preview.
 message DeleteFolderRequest {
   // Required. Name of the folder.
   // Format: `projects/{project}/buckets/{bucket}/folders/{folder}`
@@ -274,17 +292,19 @@ message DeleteFolderRequest {
   optional int64 if_metageneration_not_match = 4;
 
   // Optional. A unique identifier for this request. UUID is the recommended
-  // format, but other formats are still accepted. This request is only
-  // idempotent if a `request_id` is provided.
+  // format, but other formats are still accepted.
   string request_id = 5 [
     (google.api.field_info).format = UUID4,
     (google.api.field_behavior) = OPTIONAL
   ];
 }
 
-// Request message for ListFolders.
+// Request message for ListFolders. This operation is only applicable to a
+// hierarchical namespace enabled bucket.
+// Hierarchical namespace buckets are in allowlist preview.
 message ListFoldersRequest {
-  // Required. Name of the bucket in which to look for folders.
+  // Required. Name of the bucket in which to look for folders. The bucket must
+  // be a hierarchical namespace enabled bucket.
   string parent = 1 [
     (google.api.field_behavior) = REQUIRED,
     (google.api.resource_reference) = {
@@ -339,7 +359,9 @@ message ListFoldersResponse {
   string next_page_token = 2;
 }
 
-// Request message for RenameFolder.
+// Request message for RenameFolder. This operation is only applicable to a
+// hierarchical namespace enabled bucket.
+// Hierarchical namespace buckets are in allowlist preview.
 message RenameFolderRequest {
   // Required. Name of the source folder being renamed.
   // Format: `projects/{project}/buckets/{bucket}/folders/{folder}`