diff --git a/output/schema/schema.json b/output/schema/schema.json
index 6d626e1b6a..be9035b64c 100644
--- a/output/schema/schema.json
+++ b/output/schema/schema.json
@@ -39583,6 +39583,25 @@
                 }
               }
             }
+          },
+          {
+            "availability": {
+              "serverless": {
+                "featureFlag": "serverless.cross_project.enabled",
+                "stability": "stable",
+                "visibility": "feature_flag"
+              }
+            },
+            "description": "Specifies a subset of projects to target for the search using project\nmetadata tags in a subset of Lucene query syntax.\nAllowed Lucene queries: the _alias tag and a single value (possibly wildcarded).\nExamples:\n _alias:my-project\n _alias:_origin\n _alias:*pr*\nSupported in serverless only.",
+            "name": "project_routing",
+            "required": false,
+            "type": {
+              "kind": "instance_of",
+              "type": {
+                "name": "ProjectRouting",
+                "namespace": "_types"
+              }
+            }
           }
         ]
       },
@@ -40345,7 +40364,7 @@
           }
         }
       ],
-      "specLocation": "_global/search/SearchRequest.ts#L54-L608"
+      "specLocation": "_global/search/SearchRequest.ts#L54-L620"
     },
     {
       "kind": "response",
@@ -101464,6 +101483,25 @@
                 }
               }
             }
+          },
+          {
+            "availability": {
+              "serverless": {
+                "featureFlag": "serverless.cross_project.enabled",
+                "stability": "stable",
+                "visibility": "feature_flag"
+              }
+            },
+            "description": "Specifies a subset of projects to target for the search using project\nmetadata tags in a subset of Lucene query syntax.\nAllowed Lucene queries: the _alias tag and a single value (possibly wildcarded).\nExamples:\n _alias:my-project\n _alias:_origin\n _alias:*pr*\nSupported in serverless only.",
+            "name": "project_routing",
+            "required": false,
+            "type": {
+              "kind": "instance_of",
+              "type": {
+                "name": "ProjectRouting",
+                "namespace": "_types"
+              }
+            }
           }
         ]
       },
@@ -102092,7 +102130,7 @@
           }
         }
       ],
-      "specLocation": "async_search/submit/AsyncSearchSubmitRequest.ts#L55-L325"
+      "specLocation": "async_search/submit/AsyncSearchSubmitRequest.ts#L55-L337"
     },
     {
       "kind": "response",
diff --git a/output/typescript/types.ts b/output/typescript/types.ts
index 0c16a633de..593e19a193 100644
--- a/output/typescript/types.ts
+++ b/output/typescript/types.ts
@@ -1250,6 +1250,7 @@ export interface SearchRequest extends RequestBase {
     pit?: SearchPointInTimeReference
     runtime_mappings?: MappingRuntimeFields
     stats?: string[]
+    project_routing?: ProjectRouting
   }
 }
 
@@ -7344,6 +7345,7 @@ export interface AsyncSearchSubmitRequest extends RequestBase {
     pit?: SearchPointInTimeReference
     runtime_mappings?: MappingRuntimeFields
     stats?: string[]
+    project_routing?: ProjectRouting
   }
 }
 
diff --git a/specification/_global/search/SearchRequest.ts b/specification/_global/search/SearchRequest.ts
index 8f528160ac..1c7985c310 100644
--- a/specification/_global/search/SearchRequest.ts
+++ b/specification/_global/search/SearchRequest.ts
@@ -604,5 +604,17 @@ export interface Request extends RequestBase {
      * You can retrieve these stats using the indices stats API.
      */
     stats?: string[]
+    /**
+     * Specifies a subset of projects to target for the search using project
+     * metadata tags in a subset of Lucene query syntax.
+     * Allowed Lucene queries: the _alias tag and a single value (possibly wildcarded).
+     * Examples:
+     *  _alias:my-project
+     *  _alias:_origin
+     *  _alias:*pr*
+     * Supported in serverless only.
+     * @availability serverless stability=stable visibility=feature_flag feature_flag=serverless.cross_project.enabled
+     */
+    project_routing?: ProjectRouting
   }
 }
diff --git a/specification/async_search/submit/AsyncSearchSubmitRequest.ts b/specification/async_search/submit/AsyncSearchSubmitRequest.ts
index faaa98f380..30673a56ea 100644
--- a/specification/async_search/submit/AsyncSearchSubmitRequest.ts
+++ b/specification/async_search/submit/AsyncSearchSubmitRequest.ts
@@ -321,5 +321,17 @@ export interface Request extends RequestBase {
      * the indices stats API.
      */
     stats?: string[]
+    /**
+     * Specifies a subset of projects to target for the search using project
+     * metadata tags in a subset of Lucene query syntax.
+     * Allowed Lucene queries: the _alias tag and a single value (possibly wildcarded).
+     * Examples:
+     *  _alias:my-project
+     *  _alias:_origin
+     *  _alias:*pr*
+     * Supported in serverless only.
+     * @availability serverless stability=stable visibility=feature_flag feature_flag=serverless.cross_project.enabled
+     */
+    project_routing?: ProjectRouting
   }
 }