diff --git a/rest-api-spec/src/main/resources/rest-api-spec/api/indices.exists.json b/rest-api-spec/src/main/resources/rest-api-spec/api/indices.exists.json
index b84f4d2cacbf3..04d1b9115ba4d 100644
--- a/rest-api-spec/src/main/resources/rest-api-spec/api/indices.exists.json
+++ b/rest-api-spec/src/main/resources/rest-api-spec/api/indices.exists.json
@@ -13,6 +13,10 @@
         }
       },
       "params": {
+        "include_type_name": {
+          "type" : "boolean",
+          "description" : "Whether to add the type name to the response (default: false)"
+        },
         "local": {
           "type": "boolean",
           "description": "Return local information, do not retrieve the state from master node (default: false)"