diff --git a/src/main/java/com/google/api/codegen/transformer/csharp/CSharpSurfaceNamer.java b/src/main/java/com/google/api/codegen/transformer/csharp/CSharpSurfaceNamer.java
index 41c202f8be..b2c3fc482a 100644
--- a/src/main/java/com/google/api/codegen/transformer/csharp/CSharpSurfaceNamer.java
+++ b/src/main/java/com/google/api/codegen/transformer/csharp/CSharpSurfaceNamer.java
@@ -396,8 +396,10 @@ public String getAndSaveOperationResponseTypeName(
       Method method, ModelTypeTable typeTable, GapicMethodConfig methodConfig) {
     String responseTypeName =
         typeTable.getFullNameFor(methodConfig.getLongRunningConfig().getReturnType());
+    String metaTypeName =
+        typeTable.getFullNameFor(methodConfig.getLongRunningConfig().getMetadataType());
     return typeTable.getAndSaveNicknameForContainer(
-        "Google.LongRunning.Operation", responseTypeName);
+        "Google.LongRunning.Operation", responseTypeName, metaTypeName);
   }
 
   @Override
diff --git a/src/main/java/com/google/api/codegen/util/csharp/CSharpTypeTable.java b/src/main/java/com/google/api/codegen/util/csharp/CSharpTypeTable.java
index fc33337fdd..4b77533c31 100644
--- a/src/main/java/com/google/api/codegen/util/csharp/CSharpTypeTable.java
+++ b/src/main/java/com/google/api/codegen/util/csharp/CSharpTypeTable.java
@@ -46,6 +46,7 @@ public TypeName getTypeName(String fullName) {
       String containerTypeName = fullName.substring(0, firstGenericOpenIndex);
       List<String> genericParamNames =
           Splitter.on(',')
+              .trimResults()
               .splitToList(fullName.substring(firstGenericOpenIndex + 1, lastGenericCloseIndex));
       return getContainerTypeName(
           containerTypeName, genericParamNames.toArray(new String[genericParamNames.size()]));
@@ -76,7 +77,7 @@ public TypeName getContainerTypeName(String containerFullName, String... element
     for (int i = 0; i < elementTypeNames.length; i++) {
       elementTypeNames[i] = getTypeName(elementFullNames[i]);
     }
-    String argPattern = Joiner.on(",").join(Collections.nCopies(elementTypeNames.length, "%i"));
+    String argPattern = Joiner.on(", ").join(Collections.nCopies(elementTypeNames.length, "%i"));
     String pattern = "%s<" + argPattern + ">";
     return new TypeName(
         containerTypeName.getFullName(),
diff --git a/src/test/java/com/google/api/codegen/testdata/csharp_gapic_client_library.baseline b/src/test/java/com/google/api/codegen/testdata/csharp_gapic_client_library.baseline
index cd2a43d1b8..136ddb1681 100644
--- a/src/test/java/com/google/api/codegen/testdata/csharp_gapic_client_library.baseline
+++ b/src/test/java/com/google/api/codegen/testdata/csharp_gapic_client_library.baseline
@@ -3544,7 +3544,7 @@ namespace Google.Example.Library.V1
         /// <returns>
         /// A Task containing the RPC response.
         /// </returns>
-        public virtual Task<Operation<Book>> GetBigBookAsync(
+        public virtual Task<Operation<Book, GetBigBookMetadata>> GetBigBookAsync(
             BookName name,
             CallSettings callSettings = null) => GetBigBookAsync(
                 new GetBookRequest
@@ -3565,7 +3565,7 @@ namespace Google.Example.Library.V1
         /// <returns>
         /// A Task containing the RPC response.
         /// </returns>
-        public virtual Task<Operation<Book>> GetBigBookAsync(
+        public virtual Task<Operation<Book, GetBigBookMetadata>> GetBigBookAsync(
             BookName name,
             CancellationToken cancellationToken) => GetBigBookAsync(
                 name,
@@ -3583,7 +3583,7 @@ namespace Google.Example.Library.V1
         /// <returns>
         /// The RPC response.
         /// </returns>
-        public virtual Operation<Book> GetBigBook(
+        public virtual Operation<Book, GetBigBookMetadata> GetBigBook(
             BookName name,
             CallSettings callSettings = null) => GetBigBook(
                 new GetBookRequest
@@ -3604,7 +3604,7 @@ namespace Google.Example.Library.V1
         /// <returns>
         /// A Task containing the RPC response.
         /// </returns>
-        public virtual Task<Operation<Book>> GetBigBookAsync(
+        public virtual Task<Operation<Book, GetBigBookMetadata>> GetBigBookAsync(
             GetBookRequest request,
             CallSettings callSettings = null)
         {
@@ -3617,9 +3617,9 @@ namespace Google.Example.Library.V1
         /// <param name="operationName">The name of a previously invoked operation. Must not be <c>null</c> or empty.</param>
         /// <param name="callSettings">If not null, applies overrides to this RPC call.</param>
         /// <returns>A task representing the result of polling the operation.</returns>
-        public virtual Task<Operation<Book>> PollOnceGetBigBookAsync(
+        public virtual Task<Operation<Book, GetBigBookMetadata>> PollOnceGetBigBookAsync(
             string operationName,
-            CallSettings callSettings = null) => Operation<Book>.PollOnceFromNameAsync(
+            CallSettings callSettings = null) => Operation<Book, GetBigBookMetadata>.PollOnceFromNameAsync(
                 GaxPreconditions.CheckNotNullOrEmpty(operationName, nameof(operationName)),
                 LongRunningOperationsClient,
                 callSettings);
@@ -3636,7 +3636,7 @@ namespace Google.Example.Library.V1
         /// <returns>
         /// The RPC response.
         /// </returns>
-        public virtual Operation<Book> GetBigBook(
+        public virtual Operation<Book, GetBigBookMetadata> GetBigBook(
             GetBookRequest request,
             CallSettings callSettings = null)
         {
@@ -3649,9 +3649,9 @@ namespace Google.Example.Library.V1
         /// <param name="operationName">The name of a previously invoked operation. Must not be <c>null</c> or empty.</param>
         /// <param name="callSettings">If not null, applies overrides to this RPC call.</param>
         /// <returns>The result of polling the operation.</returns>
-        public virtual Operation<Book> PollOnceGetBigBook(
+        public virtual Operation<Book, GetBigBookMetadata> PollOnceGetBigBook(
             string operationName,
-            CallSettings callSettings = null) => Operation<Book>.PollOnceFromName(
+            CallSettings callSettings = null) => Operation<Book, GetBigBookMetadata>.PollOnceFromName(
                 GaxPreconditions.CheckNotNullOrEmpty(operationName, nameof(operationName)),
                 LongRunningOperationsClient,
                 callSettings);
@@ -3668,7 +3668,7 @@ namespace Google.Example.Library.V1
         /// <returns>
         /// A Task containing the RPC response.
         /// </returns>
-        public virtual Task<Operation<Empty>> GetBigNothingAsync(
+        public virtual Task<Operation<Empty, GetBigBookMetadata>> GetBigNothingAsync(
             BookName name,
             CallSettings callSettings = null) => GetBigNothingAsync(
                 new GetBookRequest
@@ -3689,7 +3689,7 @@ namespace Google.Example.Library.V1
         /// <returns>
         /// A Task containing the RPC response.
         /// </returns>
-        public virtual Task<Operation<Empty>> GetBigNothingAsync(
+        public virtual Task<Operation<Empty, GetBigBookMetadata>> GetBigNothingAsync(
             BookName name,
             CancellationToken cancellationToken) => GetBigNothingAsync(
                 name,
@@ -3707,7 +3707,7 @@ namespace Google.Example.Library.V1
         /// <returns>
         /// The RPC response.
         /// </returns>
-        public virtual Operation<Empty> GetBigNothing(
+        public virtual Operation<Empty, GetBigBookMetadata> GetBigNothing(
             BookName name,
             CallSettings callSettings = null) => GetBigNothing(
                 new GetBookRequest
@@ -3728,7 +3728,7 @@ namespace Google.Example.Library.V1
         /// <returns>
         /// A Task containing the RPC response.
         /// </returns>
-        public virtual Task<Operation<Empty>> GetBigNothingAsync(
+        public virtual Task<Operation<Empty, GetBigBookMetadata>> GetBigNothingAsync(
             GetBookRequest request,
             CallSettings callSettings = null)
         {
@@ -3741,9 +3741,9 @@ namespace Google.Example.Library.V1
         /// <param name="operationName">The name of a previously invoked operation. Must not be <c>null</c> or empty.</param>
         /// <param name="callSettings">If not null, applies overrides to this RPC call.</param>
         /// <returns>A task representing the result of polling the operation.</returns>
-        public virtual Task<Operation<Empty>> PollOnceGetBigNothingAsync(
+        public virtual Task<Operation<Empty, GetBigBookMetadata>> PollOnceGetBigNothingAsync(
             string operationName,
-            CallSettings callSettings = null) => Operation<Empty>.PollOnceFromNameAsync(
+            CallSettings callSettings = null) => Operation<Empty, GetBigBookMetadata>.PollOnceFromNameAsync(
                 GaxPreconditions.CheckNotNullOrEmpty(operationName, nameof(operationName)),
                 LongRunningOperationsClient,
                 callSettings);
@@ -3760,7 +3760,7 @@ namespace Google.Example.Library.V1
         /// <returns>
         /// The RPC response.
         /// </returns>
-        public virtual Operation<Empty> GetBigNothing(
+        public virtual Operation<Empty, GetBigBookMetadata> GetBigNothing(
             GetBookRequest request,
             CallSettings callSettings = null)
         {
@@ -3773,9 +3773,9 @@ namespace Google.Example.Library.V1
         /// <param name="operationName">The name of a previously invoked operation. Must not be <c>null</c> or empty.</param>
         /// <param name="callSettings">If not null, applies overrides to this RPC call.</param>
         /// <returns>The result of polling the operation.</returns>
-        public virtual Operation<Empty> PollOnceGetBigNothing(
+        public virtual Operation<Empty, GetBigBookMetadata> PollOnceGetBigNothing(
             string operationName,
-            CallSettings callSettings = null) => Operation<Empty>.PollOnceFromName(
+            CallSettings callSettings = null) => Operation<Empty, GetBigBookMetadata>.PollOnceFromName(
                 GaxPreconditions.CheckNotNullOrEmpty(operationName, nameof(operationName)),
                 LongRunningOperationsClient,
                 callSettings);
@@ -5559,7 +5559,7 @@ namespace Google.Example.Library.V1
             Modify_DiscussBookRequestCallSettings(ref callSettings);
             BidirectionalStreamingSettings effectiveStreamingSettings =
                 streamingSettings ?? _callDiscussBook.StreamingSettings;
-            AsyncDuplexStreamingCall<DiscussBookRequest,Comment> call =
+            AsyncDuplexStreamingCall<DiscussBookRequest, Comment> call =
                 _callDiscussBook.Call(callSettings);
             BufferedClientStreamWriter<DiscussBookRequest> writeBuffer =
                 new BufferedClientStreamWriter<DiscussBookRequest>(
@@ -5581,7 +5581,7 @@ namespace Google.Example.Library.V1
             /// instance associated with this streaming call.</param>
             public DiscussBookStreamImpl(
                 LibraryServiceClientImpl service,
-                AsyncDuplexStreamingCall<DiscussBookRequest,Comment> call,
+                AsyncDuplexStreamingCall<DiscussBookRequest, Comment> call,
                 BufferedClientStreamWriter<DiscussBookRequest> writeBuffer)
             {
                 _service = service;
@@ -5599,7 +5599,7 @@ namespace Google.Example.Library.V1
             }
 
             /// <inheritdoc/>
-            public override AsyncDuplexStreamingCall<DiscussBookRequest,Comment> GrpcCall { get; }
+            public override AsyncDuplexStreamingCall<DiscussBookRequest, Comment> GrpcCall { get; }
 
             /// <inheritdoc/>
             public override Task TryWriteAsync(DiscussBookRequest message) =>
@@ -5762,12 +5762,12 @@ namespace Google.Example.Library.V1
         /// <returns>
         /// A Task containing the RPC response.
         /// </returns>
-        public override async Task<Operation<Book>> GetBigBookAsync(
+        public override async Task<Operation<Book, GetBigBookMetadata>> GetBigBookAsync(
             GetBookRequest request,
             CallSettings callSettings = null)
         {
             Modify_GetBookRequest(ref request, ref callSettings);
-            return new Operation<Book>(
+            return new Operation<Book, GetBigBookMetadata>(
                 await _callGetBigBook.Async(request, callSettings).ConfigureAwait(false), LongRunningOperationsClient);
         }
 
@@ -5783,12 +5783,12 @@ namespace Google.Example.Library.V1
         /// <returns>
         /// The RPC response.
         /// </returns>
-        public override Operation<Book> GetBigBook(
+        public override Operation<Book, GetBigBookMetadata> GetBigBook(
             GetBookRequest request,
             CallSettings callSettings = null)
         {
             Modify_GetBookRequest(ref request, ref callSettings);
-            return new Operation<Book>(
+            return new Operation<Book, GetBigBookMetadata>(
                 _callGetBigBook.Sync(request, callSettings), LongRunningOperationsClient);
         }
 
@@ -5804,12 +5804,12 @@ namespace Google.Example.Library.V1
         /// <returns>
         /// A Task containing the RPC response.
         /// </returns>
-        public override async Task<Operation<Empty>> GetBigNothingAsync(
+        public override async Task<Operation<Empty, GetBigBookMetadata>> GetBigNothingAsync(
             GetBookRequest request,
             CallSettings callSettings = null)
         {
             Modify_GetBookRequest(ref request, ref callSettings);
-            return new Operation<Empty>(
+            return new Operation<Empty, GetBigBookMetadata>(
                 await _callGetBigNothing.Async(request, callSettings).ConfigureAwait(false), LongRunningOperationsClient);
         }
 
@@ -5825,12 +5825,12 @@ namespace Google.Example.Library.V1
         /// <returns>
         /// The RPC response.
         /// </returns>
-        public override Operation<Empty> GetBigNothing(
+        public override Operation<Empty, GetBigBookMetadata> GetBigNothing(
             GetBookRequest request,
             CallSettings callSettings = null)
         {
             Modify_GetBookRequest(ref request, ref callSettings);
-            return new Operation<Empty>(
+            return new Operation<Empty, GetBigBookMetadata>(
                 _callGetBigNothing.Sync(request, callSettings), LongRunningOperationsClient);
         }
 
diff --git a/src/test/java/com/google/api/codegen/testdata/csharp_gapic_snippets_library.baseline b/src/test/java/com/google/api/codegen/testdata/csharp_gapic_snippets_library.baseline
index e7899457fd..1c10e7cfe7 100644
--- a/src/test/java/com/google/api/codegen/testdata/csharp_gapic_snippets_library.baseline
+++ b/src/test/java/com/google/api/codegen/testdata/csharp_gapic_snippets_library.baseline
@@ -209,7 +209,7 @@ namespace Google.Example.Library.V1.Snippets
             // Create client
             LibraryServiceClient libraryServiceClient = await LibraryServiceClient.CreateAsync();
             // Make the request
-            PagedAsyncEnumerable<ListShelvesResponse,Shelf> response =
+            PagedAsyncEnumerable<ListShelvesResponse, Shelf> response =
                 libraryServiceClient.ListShelvesAsync();
 
             // Iterate over all response items, lazily performing RPCs as required
@@ -250,7 +250,7 @@ namespace Google.Example.Library.V1.Snippets
             // Create client
             LibraryServiceClient libraryServiceClient = LibraryServiceClient.Create();
             // Make the request
-            PagedEnumerable<ListShelvesResponse,Shelf> response =
+            PagedEnumerable<ListShelvesResponse, Shelf> response =
                 libraryServiceClient.ListShelves();
 
             // Iterate over all response items, lazily performing RPCs as required
@@ -293,7 +293,7 @@ namespace Google.Example.Library.V1.Snippets
             // Initialize request argument(s)
             ListShelvesRequest request = new ListShelvesRequest();
             // Make the request
-            PagedAsyncEnumerable<ListShelvesResponse,Shelf> response =
+            PagedAsyncEnumerable<ListShelvesResponse, Shelf> response =
                 libraryServiceClient.ListShelvesAsync(request);
 
             // Iterate over all response items, lazily performing RPCs as required
@@ -336,7 +336,7 @@ namespace Google.Example.Library.V1.Snippets
             // Initialize request argument(s)
             ListShelvesRequest request = new ListShelvesRequest();
             // Make the request
-            PagedEnumerable<ListShelvesResponse,Shelf> response =
+            PagedEnumerable<ListShelvesResponse, Shelf> response =
                 libraryServiceClient.ListShelves(request);
 
             // Iterate over all response items, lazily performing RPCs as required
@@ -685,7 +685,7 @@ namespace Google.Example.Library.V1.Snippets
             ShelfName name = new ShelfName("[SHELF_ID]");
             string filter = "";
             // Make the request
-            PagedAsyncEnumerable<ListBooksResponse,Book> response =
+            PagedAsyncEnumerable<ListBooksResponse, Book> response =
                 libraryServiceClient.ListBooksAsync(name, filter);
 
             // Iterate over all response items, lazily performing RPCs as required
@@ -729,7 +729,7 @@ namespace Google.Example.Library.V1.Snippets
             ShelfName name = new ShelfName("[SHELF_ID]");
             string filter = "";
             // Make the request
-            PagedEnumerable<ListBooksResponse,Book> response =
+            PagedEnumerable<ListBooksResponse, Book> response =
                 libraryServiceClient.ListBooks(name, filter);
 
             // Iterate over all response items, lazily performing RPCs as required
@@ -775,7 +775,7 @@ namespace Google.Example.Library.V1.Snippets
                 ShelfName = new ShelfName("[SHELF_ID]"),
             };
             // Make the request
-            PagedAsyncEnumerable<ListBooksResponse,Book> response =
+            PagedAsyncEnumerable<ListBooksResponse, Book> response =
                 libraryServiceClient.ListBooksAsync(request);
 
             // Iterate over all response items, lazily performing RPCs as required
@@ -821,7 +821,7 @@ namespace Google.Example.Library.V1.Snippets
                 ShelfName = new ShelfName("[SHELF_ID]"),
             };
             // Make the request
-            PagedEnumerable<ListBooksResponse,Book> response =
+            PagedEnumerable<ListBooksResponse, Book> response =
                 libraryServiceClient.ListBooks(request);
 
             // Iterate over all response items, lazily performing RPCs as required
@@ -1066,7 +1066,7 @@ namespace Google.Example.Library.V1.Snippets
             // Create client
             LibraryServiceClient libraryServiceClient = await LibraryServiceClient.CreateAsync();
             // Make the request
-            PagedAsyncEnumerable<ListStringsResponse,IResourceName> response =
+            PagedAsyncEnumerable<ListStringsResponse, IResourceName> response =
                 libraryServiceClient.ListStringsAsync();
 
             // Iterate over all response items, lazily performing RPCs as required
@@ -1107,7 +1107,7 @@ namespace Google.Example.Library.V1.Snippets
             // Create client
             LibraryServiceClient libraryServiceClient = LibraryServiceClient.Create();
             // Make the request
-            PagedEnumerable<ListStringsResponse,IResourceName> response =
+            PagedEnumerable<ListStringsResponse, IResourceName> response =
                 libraryServiceClient.ListStrings();
 
             // Iterate over all response items, lazily performing RPCs as required
@@ -1150,7 +1150,7 @@ namespace Google.Example.Library.V1.Snippets
             // Initialize request argument(s)
             IResourceName name = new ShelfName("[SHELF_ID]");
             // Make the request
-            PagedAsyncEnumerable<ListStringsResponse,IResourceName> response =
+            PagedAsyncEnumerable<ListStringsResponse, IResourceName> response =
                 libraryServiceClient.ListStringsAsync(name);
 
             // Iterate over all response items, lazily performing RPCs as required
@@ -1193,7 +1193,7 @@ namespace Google.Example.Library.V1.Snippets
             // Initialize request argument(s)
             IResourceName name = new ShelfName("[SHELF_ID]");
             // Make the request
-            PagedEnumerable<ListStringsResponse,IResourceName> response =
+            PagedEnumerable<ListStringsResponse, IResourceName> response =
                 libraryServiceClient.ListStrings(name);
 
             // Iterate over all response items, lazily performing RPCs as required
@@ -1236,7 +1236,7 @@ namespace Google.Example.Library.V1.Snippets
             // Initialize request argument(s)
             ListStringsRequest request = new ListStringsRequest();
             // Make the request
-            PagedAsyncEnumerable<ListStringsResponse,IResourceName> response =
+            PagedAsyncEnumerable<ListStringsResponse, IResourceName> response =
                 libraryServiceClient.ListStringsAsync(request);
 
             // Iterate over all response items, lazily performing RPCs as required
@@ -1279,7 +1279,7 @@ namespace Google.Example.Library.V1.Snippets
             // Initialize request argument(s)
             ListStringsRequest request = new ListStringsRequest();
             // Make the request
-            PagedEnumerable<ListStringsResponse,IResourceName> response =
+            PagedEnumerable<ListStringsResponse, IResourceName> response =
                 libraryServiceClient.ListStrings(request);
 
             // Iterate over all response items, lazily performing RPCs as required
@@ -1644,7 +1644,7 @@ namespace Google.Example.Library.V1.Snippets
             };
             IEnumerable<ShelfName> shelves = new List<ShelfName>();
             // Make the request
-            PagedAsyncEnumerable<FindRelatedBooksResponse,BookName> response =
+            PagedAsyncEnumerable<FindRelatedBooksResponse, BookName> response =
                 libraryServiceClient.FindRelatedBooksAsync(names, shelves);
 
             // Iterate over all response items, lazily performing RPCs as required
@@ -1691,7 +1691,7 @@ namespace Google.Example.Library.V1.Snippets
             };
             IEnumerable<ShelfName> shelves = new List<ShelfName>();
             // Make the request
-            PagedEnumerable<FindRelatedBooksResponse,BookName> response =
+            PagedEnumerable<FindRelatedBooksResponse, BookName> response =
                 libraryServiceClient.FindRelatedBooks(names, shelves);
 
             // Iterate over all response items, lazily performing RPCs as required
@@ -1740,7 +1740,7 @@ namespace Google.Example.Library.V1.Snippets
                 ShelvesAsShelfNames = { },
             };
             // Make the request
-            PagedAsyncEnumerable<FindRelatedBooksResponse,BookName> response =
+            PagedAsyncEnumerable<FindRelatedBooksResponse, BookName> response =
                 libraryServiceClient.FindRelatedBooksAsync(request);
 
             // Iterate over all response items, lazily performing RPCs as required
@@ -1789,7 +1789,7 @@ namespace Google.Example.Library.V1.Snippets
                 ShelvesAsShelfNames = { },
             };
             // Make the request
-            PagedEnumerable<FindRelatedBooksResponse,BookName> response =
+            PagedEnumerable<FindRelatedBooksResponse, BookName> response =
                 libraryServiceClient.FindRelatedBooks(request);
 
             // Iterate over all response items, lazily performing RPCs as required
@@ -1951,11 +1951,11 @@ namespace Google.Example.Library.V1.Snippets
             // Initialize request argument(s)
             BookName name = new BookName("[SHELF_ID]", "[BOOK_ID]");
             // Make the request
-            Operation<Book> response =
+            Operation<Book, GetBigBookMetadata> response =
                 await libraryServiceClient.GetBigBookAsync(name);
 
             // Poll until the returned long-running operation is complete
-            Operation<Book> completedResponse =
+            Operation<Book, GetBigBookMetadata> completedResponse =
                 await response.PollUntilCompletedAsync();
             // Retrieve the operation result
             Book result = completedResponse.Result;
@@ -1963,7 +1963,7 @@ namespace Google.Example.Library.V1.Snippets
             // Or get the name of the operation
             string operationName = response.Name;
             // This name can be stored, then the long-running operation retrieved later by name
-            Operation<Book> retrievedResponse =
+            Operation<Book, GetBigBookMetadata> retrievedResponse =
                 await libraryServiceClient.PollOnceGetBigBookAsync(operationName);
             // Check if the retrieved long-running operation has completed
             if (retrievedResponse.IsCompleted)
@@ -1982,11 +1982,11 @@ namespace Google.Example.Library.V1.Snippets
             // Initialize request argument(s)
             BookName name = new BookName("[SHELF_ID]", "[BOOK_ID]");
             // Make the request
-            Operation<Book> response =
+            Operation<Book, GetBigBookMetadata> response =
                 libraryServiceClient.GetBigBook(name);
 
             // Poll until the returned long-running operation is complete
-            Operation<Book> completedResponse =
+            Operation<Book, GetBigBookMetadata> completedResponse =
                 response.PollUntilCompleted();
             // Retrieve the operation result
             Book result = completedResponse.Result;
@@ -1994,7 +1994,7 @@ namespace Google.Example.Library.V1.Snippets
             // Or get the name of the operation
             string operationName = response.Name;
             // This name can be stored, then the long-running operation retrieved later by name
-            Operation<Book> retrievedResponse =
+            Operation<Book, GetBigBookMetadata> retrievedResponse =
                 libraryServiceClient.PollOnceGetBigBook(operationName);
             // Check if the retrieved long-running operation has completed
             if (retrievedResponse.IsCompleted)
@@ -2016,11 +2016,11 @@ namespace Google.Example.Library.V1.Snippets
                 BookName = new BookName("[SHELF_ID]", "[BOOK_ID]"),
             };
             // Make the request
-            Operation<Book> response =
+            Operation<Book, GetBigBookMetadata> response =
                 await libraryServiceClient.GetBigBookAsync(request);
 
             // Poll until the returned long-running operation is complete
-            Operation<Book> completedResponse =
+            Operation<Book, GetBigBookMetadata> completedResponse =
                 await response.PollUntilCompletedAsync();
             // Retrieve the operation result
             Book result = completedResponse.Result;
@@ -2028,7 +2028,7 @@ namespace Google.Example.Library.V1.Snippets
             // Or get the name of the operation
             string operationName = response.Name;
             // This name can be stored, then the long-running operation retrieved later by name
-            Operation<Book> retrievedResponse =
+            Operation<Book, GetBigBookMetadata> retrievedResponse =
                 await libraryServiceClient.PollOnceGetBigBookAsync(operationName);
             // Check if the retrieved long-running operation has completed
             if (retrievedResponse.IsCompleted)
@@ -2050,11 +2050,11 @@ namespace Google.Example.Library.V1.Snippets
                 BookName = new BookName("[SHELF_ID]", "[BOOK_ID]"),
             };
             // Make the request
-            Operation<Book> response =
+            Operation<Book, GetBigBookMetadata> response =
                 libraryServiceClient.GetBigBook(request);
 
             // Poll until the returned long-running operation is complete
-            Operation<Book> completedResponse =
+            Operation<Book, GetBigBookMetadata> completedResponse =
                 response.PollUntilCompleted();
             // Retrieve the operation result
             Book result = completedResponse.Result;
@@ -2062,7 +2062,7 @@ namespace Google.Example.Library.V1.Snippets
             // Or get the name of the operation
             string operationName = response.Name;
             // This name can be stored, then the long-running operation retrieved later by name
-            Operation<Book> retrievedResponse =
+            Operation<Book, GetBigBookMetadata> retrievedResponse =
                 libraryServiceClient.PollOnceGetBigBook(operationName);
             // Check if the retrieved long-running operation has completed
             if (retrievedResponse.IsCompleted)
@@ -2082,18 +2082,18 @@ namespace Google.Example.Library.V1.Snippets
             // Initialize request argument(s)
             BookName name = new BookName("[SHELF_ID]", "[BOOK_ID]");
             // Make the request
-            Operation<Empty> response =
+            Operation<Empty, GetBigBookMetadata> response =
                 await libraryServiceClient.GetBigNothingAsync(name);
 
             // Poll until the returned long-running operation is complete
-            Operation<Empty> completedResponse =
+            Operation<Empty, GetBigBookMetadata> completedResponse =
                 await response.PollUntilCompletedAsync();
             // The long-running operation is now complete.
 
             // Or get the name of the operation
             string operationName = response.Name;
             // This name can be stored, then the long-running operation retrieved later by name
-            Operation<Empty> retrievedResponse =
+            Operation<Empty, GetBigBookMetadata> retrievedResponse =
                 await libraryServiceClient.PollOnceGetBigNothingAsync(operationName);
             // Check if the retrieved long-running operation has completed
             if (retrievedResponse.IsCompleted)
@@ -2111,18 +2111,18 @@ namespace Google.Example.Library.V1.Snippets
             // Initialize request argument(s)
             BookName name = new BookName("[SHELF_ID]", "[BOOK_ID]");
             // Make the request
-            Operation<Empty> response =
+            Operation<Empty, GetBigBookMetadata> response =
                 libraryServiceClient.GetBigNothing(name);
 
             // Poll until the returned long-running operation is complete
-            Operation<Empty> completedResponse =
+            Operation<Empty, GetBigBookMetadata> completedResponse =
                 response.PollUntilCompleted();
             // The long-running operation is now complete.
 
             // Or get the name of the operation
             string operationName = response.Name;
             // This name can be stored, then the long-running operation retrieved later by name
-            Operation<Empty> retrievedResponse =
+            Operation<Empty, GetBigBookMetadata> retrievedResponse =
                 libraryServiceClient.PollOnceGetBigNothing(operationName);
             // Check if the retrieved long-running operation has completed
             if (retrievedResponse.IsCompleted)
@@ -2143,18 +2143,18 @@ namespace Google.Example.Library.V1.Snippets
                 BookName = new BookName("[SHELF_ID]", "[BOOK_ID]"),
             };
             // Make the request
-            Operation<Empty> response =
+            Operation<Empty, GetBigBookMetadata> response =
                 await libraryServiceClient.GetBigNothingAsync(request);
 
             // Poll until the returned long-running operation is complete
-            Operation<Empty> completedResponse =
+            Operation<Empty, GetBigBookMetadata> completedResponse =
                 await response.PollUntilCompletedAsync();
             // The long-running operation is now complete.
 
             // Or get the name of the operation
             string operationName = response.Name;
             // This name can be stored, then the long-running operation retrieved later by name
-            Operation<Empty> retrievedResponse =
+            Operation<Empty, GetBigBookMetadata> retrievedResponse =
                 await libraryServiceClient.PollOnceGetBigNothingAsync(operationName);
             // Check if the retrieved long-running operation has completed
             if (retrievedResponse.IsCompleted)
@@ -2175,18 +2175,18 @@ namespace Google.Example.Library.V1.Snippets
                 BookName = new BookName("[SHELF_ID]", "[BOOK_ID]"),
             };
             // Make the request
-            Operation<Empty> response =
+            Operation<Empty, GetBigBookMetadata> response =
                 libraryServiceClient.GetBigNothing(request);
 
             // Poll until the returned long-running operation is complete
-            Operation<Empty> completedResponse =
+            Operation<Empty, GetBigBookMetadata> completedResponse =
                 response.PollUntilCompleted();
             // The long-running operation is now complete.
 
             // Or get the name of the operation
             string operationName = response.Name;
             // This name can be stored, then the long-running operation retrieved later by name
-            Operation<Empty> retrievedResponse =
+            Operation<Empty, GetBigBookMetadata> retrievedResponse =
                 libraryServiceClient.PollOnceGetBigNothing(operationName);
             // Check if the retrieved long-running operation has completed
             if (retrievedResponse.IsCompleted)