diff --git a/api-index-v1.json b/api-index-v1.json
index e2777613a6..a5967cd40f 100644
--- a/api-index-v1.json
+++ b/api-index-v1.json
@@ -59410,37 +59410,37 @@
       "options": {
         "csharp_namespace": {
           "valueCounts": {
-            "Google.Cloud.DiscoveryEngine.V1": 20
+            "Google.Cloud.DiscoveryEngine.V1": 21
           }
         },
         "go_package": {
           "valueCounts": {
-            "cloud.google.com/go/discoveryengine/apiv1/discoveryenginepb;discoveryenginepb": 20
+            "cloud.google.com/go/discoveryengine/apiv1/discoveryenginepb;discoveryenginepb": 21
           }
         },
         "java_multiple_files": {
           "valueCounts": {
-            "true": 20
+            "true": 21
           }
         },
         "java_package": {
           "valueCounts": {
-            "com.google.cloud.discoveryengine.v1": 20
+            "com.google.cloud.discoveryengine.v1": 21
           }
         },
         "objc_class_prefix": {
           "valueCounts": {
-            "DISCOVERYENGINE": 20
+            "DISCOVERYENGINE": 21
           }
         },
         "php_namespace": {
           "valueCounts": {
-            "Google\\Cloud\\DiscoveryEngine\\V1": 20
+            "Google\\Cloud\\DiscoveryEngine\\V1": 21
           }
         },
         "ruby_package": {
           "valueCounts": {
-            "Google::Cloud::DiscoveryEngine::V1": 20
+            "Google::Cloud::DiscoveryEngine::V1": 21
           }
         }
       },
@@ -59869,6 +59869,31 @@
             }
           ]
         },
+        {
+          "shortName": "RecommendationService",
+          "fullName": "google.cloud.discoveryengine.v1.RecommendationService",
+          "methods": [
+            {
+              "shortName": "Recommend",
+              "fullName": "google.cloud.discoveryengine.v1.RecommendationService.Recommend",
+              "mode": "UNARY",
+              "bindings": [
+                {
+                  "httpMethod": "POST",
+                  "path": "/v1/{serving_config=projects/*/locations/*/dataStores/*/servingConfigs/*}:recommend"
+                },
+                {
+                  "httpMethod": "POST",
+                  "path": "/v1/{serving_config=projects/*/locations/*/collections/*/dataStores/*/servingConfigs/*}:recommend"
+                },
+                {
+                  "httpMethod": "POST",
+                  "path": "/v1/{serving_config=projects/*/locations/*/collections/*/engines/*/servingConfigs/*}:recommend"
+                }
+              ]
+            }
+          ]
+        },
         {
           "shortName": "SchemaService",
           "fullName": "google.cloud.discoveryengine.v1.SchemaService",
@@ -60212,6 +60237,7 @@
         "google.cloud.discoveryengine.v1.DataStoreService",
         "google.cloud.discoveryengine.v1.DocumentService",
         "google.cloud.discoveryengine.v1.EngineService",
+        "google.cloud.discoveryengine.v1.RecommendationService",
         "google.cloud.discoveryengine.v1.SchemaService",
         "google.cloud.discoveryengine.v1.SearchService",
         "google.cloud.discoveryengine.v1.SiteSearchEngineService",