diff --git a/CHANGELOG.md b/CHANGELOG.md
index 09115e4..148c4ec 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,5 +1,9 @@
 cos-php-sdk-v5 Upgrade Guide
 ====================
+2.6.12 to 2.6.13
+---------
+修复部分问题
+
 2.6.11 to 2.6.12
 ---------
 1. 盲水印支持版本参数
diff --git a/src/Client.php b/src/Client.php
index 1007fe4..9d27d25 100644
--- a/src/Client.php
+++ b/src/Client.php
@@ -280,7 +280,7 @@
  * @see \Qcloud\Cos\Service::getService()
  */
 class Client extends GuzzleClient {
-    const VERSION = '2.6.12';
+    const VERSION = '2.6.13';
 
     public $httpClient;
 
diff --git a/src/Descriptions.php b/src/Descriptions.php
index 20a5bf5..16ab14a 100644
--- a/src/Descriptions.php
+++ b/src/Descriptions.php
@@ -1024,6 +1024,7 @@ public static function CreateMediaConcatJobs() {
                                             'Url' => array( 'type' => 'string', 'location' => 'xml', ),
                                             'StartTime' => array( 'type' => 'string', 'location' => 'xml', ),
                                             'EndTime' => array( 'type' => 'string', 'location' => 'xml', ),
+                                            'FragmentIndex' => array( 'type' => 'string', 'location' => 'xml', ),
                                             // 'Mode' => array( 'type' => 'string', 'location' => 'xml', ), 拼接接口不需要Mode参数
                                         ),
                                     ),