diff --git a/src/BigQuery/BigQueryClient.php b/src/BigQuery/BigQueryClient.php
index 5c51d8a58d82..cfa25d9e09a6 100644
--- a/src/BigQuery/BigQueryClient.php
+++ b/src/BigQuery/BigQueryClient.php
@@ -73,6 +73,8 @@ class BigQueryClient
      *     @type array $authCacheOptions Cache configuration options.
      *     @type callable $authHttpHandler A handler used to deliver Psr7
      *           requests specifically for authentication.
+     *     @type FetchAuthTokenInterface $credentialsFetcher A credentials
+     *           fetcher instance.
      *     @type callable $httpHandler A handler used to deliver Psr7 requests.
      *           Only valid for requests sent over REST.
      *     @type array $keyFile The contents of the service account credentials
@@ -81,6 +83,8 @@ class BigQueryClient
      *     @type string $keyFilePath The full path to your service account
      *           credentials .json file retrieved from the Google Developers
      *           Console.
+     *     @type float $requestTimeout Seconds to wait before timing out the
+     *           request. **Defaults to** `0` with REST and `60` with gRPC.
      *     @type int $retries Number of retries for a failed request. **Defaults
      *           to** `3`.
      *     @type array $scopes Scopes to be used for the request.
diff --git a/src/Datastore/DatastoreClient.php b/src/Datastore/DatastoreClient.php
index 392af7c80739..07725a41087e 100644
--- a/src/Datastore/DatastoreClient.php
+++ b/src/Datastore/DatastoreClient.php
@@ -108,6 +108,8 @@ class DatastoreClient
      *     @type array $authCacheOptions Cache configuration options.
      *     @type callable $authHttpHandler A handler used to deliver Psr7
      *           requests specifically for authentication.
+     *     @type FetchAuthTokenInterface $credentialsFetcher A credentials
+     *           fetcher instance.
      *     @type callable $httpHandler A handler used to deliver Psr7 requests.
      *           Only valid for requests sent over REST.
      *     @type array $keyFile The contents of the service account credentials
@@ -116,6 +118,8 @@ class DatastoreClient
      *     @type string $keyFilePath The full path to your service account
      *           credentials .json file retrieved from the Google Developers
      *           Console.
+     *     @type float $requestTimeout Seconds to wait before timing out the
+     *           request. **Defaults to** `0` with REST and `60` with gRPC.
      *     @type int $retries Number of retries for a failed request. **Defaults
      *           to** `3`.
      *     @type array $scopes Scopes to be used for the request.
diff --git a/src/Language/LanguageClient.php b/src/Language/LanguageClient.php
index e3a26b4afbc1..007ceabf90df 100644
--- a/src/Language/LanguageClient.php
+++ b/src/Language/LanguageClient.php
@@ -74,6 +74,8 @@ class LanguageClient
      *     @type array $authCacheOptions Cache configuration options.
      *     @type callable $authHttpHandler A handler used to deliver Psr7
      *           requests specifically for authentication.
+     *     @type FetchAuthTokenInterface $credentialsFetcher A credentials
+     *           fetcher instance.
      *     @type callable $httpHandler A handler used to deliver Psr7 requests.
      *           Only valid for requests sent over REST.
      *     @type array $keyFile The contents of the service account credentials
@@ -82,6 +84,8 @@ class LanguageClient
      *     @type string $keyFilePath The full path to your service account
      *           credentials .json file retrieved from the Google Developers
      *           Console.
+     *     @type float $requestTimeout Seconds to wait before timing out the
+     *           request. **Defaults to** `0` with REST and `60` with gRPC.
      *     @type int $retries Number of retries for a failed request.
      *           **Defaults to** `3`.
      *     @type array $scopes Scopes to be used for the request.
diff --git a/src/Logging/LoggingClient.php b/src/Logging/LoggingClient.php
index f9a1fc45aa9a..c7b8bab69bb3 100644
--- a/src/Logging/LoggingClient.php
+++ b/src/Logging/LoggingClient.php
@@ -152,6 +152,8 @@ public static function psrBatchLogger($name, array $options = [])
      *     @type array $authCacheOptions Cache configuration options.
      *     @type callable $authHttpHandler A handler used to deliver Psr7
      *           requests specifically for authentication.
+     *     @type FetchAuthTokenInterface $credentialsFetcher A credentials
+     *           fetcher instance.
      *     @type callable $httpHandler A handler used to deliver Psr7 requests.
      *           Only valid for requests sent over REST.
      *     @type array $keyFile The contents of the service account credentials
@@ -160,6 +162,8 @@ public static function psrBatchLogger($name, array $options = [])
      *     @type string $keyFilePath The full path to your service account
      *           credentials .json file retrieved from the Google Developers
      *           Console.
+     *     @type float $requestTimeout Seconds to wait before timing out the
+     *           request. **Defaults to** `0` with REST and `60` with gRPC.
      *     @type int $retries Number of retries for a failed request.
      *           **Defaults to** `3`.
      *     @type array $scopes Scopes to be used for the request.
diff --git a/src/PubSub/PubSubClient.php b/src/PubSub/PubSubClient.php
index 89ecc45336e6..462e2287309d 100644
--- a/src/PubSub/PubSubClient.php
+++ b/src/PubSub/PubSubClient.php
@@ -117,6 +117,8 @@ class PubSubClient
      *     @type array $authCacheOptions Cache configuration options.
      *     @type callable $authHttpHandler A handler used to deliver Psr7
      *           requests specifically for authentication.
+     *     @type FetchAuthTokenInterface $credentialsFetcher A credentials
+     *           fetcher instance.
      *     @type callable $httpHandler A handler used to deliver Psr7 requests.
      *           Only valid for requests sent over REST.
      *     @type array $keyFile The contents of the service account credentials
@@ -125,6 +127,8 @@ class PubSubClient
      *     @type string $keyFilePath The full path to your service account
      *           credentials .json file retrieved from the Google Developers
      *           Console.
+     *     @type float $requestTimeout Seconds to wait before timing out the
+     *           request. **Defaults to** `0` with REST and `60` with gRPC.
      *     @type int $retries Number of retries for a failed request.
      *           **Defaults to** `3`.
      *     @type array $scopes Scopes to be used for the request.
diff --git a/src/Spanner/SpannerClient.php b/src/Spanner/SpannerClient.php
index 4548ea96188f..c035172d92aa 100644
--- a/src/Spanner/SpannerClient.php
+++ b/src/Spanner/SpannerClient.php
@@ -89,13 +89,18 @@ class SpannerClient
      *           Console.
      *     @type callable $authHttpHandler A handler used to deliver Psr7
      *           requests specifically for authentication.
+     *     @type FetchAuthTokenInterface $credentialsFetcher A credentials
+     *           fetcher instance.
      *     @type callable $httpHandler A handler used to deliver Psr7 requests.
-     *     @type array $keyFile The json decoded contents of the service account
-     *           credentials .json file retrieved from the Google Developers
-     *           Console.
+     *           Only valid for requests sent over REST.
+     *     @type array $keyFile The contents of the service account credentials
+     *           .json file retrieved from the Google Developer's Console.
+     *           Ex: `json_decode(file_get_contents($path), true)`.
      *     @type string $keyFilePath The full path to your service account
      *           credentials .json file retrieved from the Google Developers
      *           Console.
+     *     @type float $requestTimeout Seconds to wait before timing out the
+     *           request. **Defaults to** `0` with REST and `60` with gRPC.
      *     @type int $retries Number of retries for a failed request.
      *           **Defaults to** `3`.
      *     @type array $scopes Scopes to be used for the request.
diff --git a/src/Speech/SpeechClient.php b/src/Speech/SpeechClient.php
index f92fad6b7d34..4417c8b8857e 100644
--- a/src/Speech/SpeechClient.php
+++ b/src/Speech/SpeechClient.php
@@ -69,6 +69,8 @@ class SpeechClient
      *     @type array $authCacheOptions Cache configuration options.
      *     @type callable $authHttpHandler A handler used to deliver Psr7
      *           requests specifically for authentication.
+     *     @type FetchAuthTokenInterface $credentialsFetcher A credentials
+     *           fetcher instance.
      *     @type callable $httpHandler A handler used to deliver Psr7 requests.
      *           Only valid for requests sent over REST.
      *     @type array $keyFile The contents of the service account credentials
@@ -77,6 +79,8 @@ class SpeechClient
      *     @type string $keyFilePath The full path to your service account
      *           credentials .json file retrieved from the Google Developers
      *           Console.
+     *     @type float $requestTimeout Seconds to wait before timing out the
+     *           request. **Defaults to** `0` with REST and `60` with gRPC.
      *     @type int $retries Number of retries for a failed request.
      *           **Defaults to** `3`.
      *     @type array $scopes Scopes to be used for the request.
diff --git a/src/Storage/StorageClient.php b/src/Storage/StorageClient.php
index d9ad6fcf8ead..7ad5bdf327d0 100644
--- a/src/Storage/StorageClient.php
+++ b/src/Storage/StorageClient.php
@@ -69,6 +69,8 @@ class StorageClient
      *     @type array $authCacheOptions Cache configuration options.
      *     @type callable $authHttpHandler A handler used to deliver Psr7
      *           requests specifically for authentication.
+     *     @type FetchAuthTokenInterface $credentialsFetcher A credentials
+     *           fetcher instance.
      *     @type callable $httpHandler A handler used to deliver Psr7 requests.
      *           Only valid for requests sent over REST.
      *     @type array $keyFile The contents of the service account credentials
@@ -77,6 +79,8 @@ class StorageClient
      *     @type string $keyFilePath The full path to your service account
      *           credentials .json file retrieved from the Google Developers
      *           Console.
+     *     @type float $requestTimeout Seconds to wait before timing out the
+     *           request. **Defaults to** `0` with REST and `60` with gRPC.
      *     @type int $retries Number of retries for a failed request.
      *           **Defaults to** `3`.
      *     @type array $scopes Scopes to be used for the request.
diff --git a/src/Trace/TraceClient.php b/src/Trace/TraceClient.php
index 91b17c3739e6..0b61af4b38a6 100644
--- a/src/Trace/TraceClient.php
+++ b/src/Trace/TraceClient.php
@@ -71,6 +71,8 @@ class TraceClient
      *     @type array $authCacheOptions Cache configuration options.
      *     @type callable $authHttpHandler A handler used to deliver Psr7
      *           requests specifically for authentication.
+     *     @type FetchAuthTokenInterface $credentialsFetcher A credentials
+     *           fetcher instance.
      *     @type callable $httpHandler A handler used to deliver Psr7 requests.
      *           Only valid for requests sent over REST.
      *     @type array $keyFile The contents of the service account credentials
@@ -79,6 +81,8 @@ class TraceClient
      *     @type string $keyFilePath The full path to your service account
      *           credentials .json file retrieved from the Google Developers
      *           Console.
+     *     @type float $requestTimeout Seconds to wait before timing out the
+     *           request. **Defaults to** `0` with REST and `60` with gRPC.
      *     @type int $retries Number of retries for a failed request.
      *           **Defaults to** `3`.
      *     @type array $scopes Scopes to be used for the request.
diff --git a/src/Translate/TranslateClient.php b/src/Translate/TranslateClient.php
index 539fde8272bd..261d970f5e49 100644
--- a/src/Translate/TranslateClient.php
+++ b/src/Translate/TranslateClient.php
@@ -77,8 +77,6 @@ class TranslateClient
      *     @type string $target The target language to assign to the client.
      *           Must be a valid ISO 639-1 language code. **Defaults to** `"en"`
      *           (English).
-     *     @type int $retries Number of retries for a failed request.
-     *           **Defaults to** `3`.
      *     @type string $projectId The project ID from the Google Developer's
      *           Console.
      *     @type CacheItemPoolInterface $authCache A cache used storing access
@@ -86,6 +84,8 @@ class TranslateClient
      *     @type array $authCacheOptions Cache configuration options.
      *     @type callable $authHttpHandler A handler used to deliver Psr7
      *           requests specifically for authentication.
+     *     @type FetchAuthTokenInterface $credentialsFetcher A credentials
+     *           fetcher instance.
      *     @type callable $httpHandler A handler used to deliver Psr7 requests.
      *           Only valid for requests sent over REST.
      *     @type array $keyFile The contents of the service account credentials
@@ -94,6 +94,8 @@ class TranslateClient
      *     @type string $keyFilePath The full path to your service account
      *           credentials .json file retrieved from the Google Developers
      *           Console.
+     *     @type float $requestTimeout Seconds to wait before timing out the
+     *           request. **Defaults to** `0` with REST and `60` with gRPC.
      *     @type int $retries Number of retries for a failed request.
      *           **Defaults to** `3`.
      *     @type array $scopes Scopes to be used for the request.
diff --git a/src/Vision/VisionClient.php b/src/Vision/VisionClient.php
index a1d0a1ef09f8..e9a32e5f6666 100644
--- a/src/Vision/VisionClient.php
+++ b/src/Vision/VisionClient.php
@@ -64,13 +64,18 @@ class VisionClient
      *     @type array $authCacheOptions Cache configuration options.
      *     @type callable $authHttpHandler A handler used to deliver Psr7
      *           requests specifically for authentication.
+     *     @type FetchAuthTokenInterface $credentialsFetcher A credentials
+     *           fetcher instance.
      *     @type callable $httpHandler A handler used to deliver Psr7 requests.
+     *           Only valid for requests sent over REST.
      *     @type array $keyFile The contents of the service account credentials
      *           .json file retrieved from the Google Developer's Console.
      *           Ex: `json_decode(file_get_contents($path), true)`.
      *     @type string $keyFilePath The full path to your service account
      *           credentials .json file retrieved from the Google Developers
      *           Console.
+     *     @type float $requestTimeout Seconds to wait before timing out the
+     *           request. **Defaults to** `0` with REST and `60` with gRPC.
      *     @type int $retries Number of retries for a failed request.
      *           **Defaults to** `3`.
      *     @type array $scopes Scopes to be used for the request.