diff --git a/src/OpenSearch/Client.php b/src/OpenSearch/Client.php
index 43f4f1ef..963a9270 100644
--- a/src/OpenSearch/Client.php
+++ b/src/OpenSearch/Client.php
@@ -2155,7 +2155,7 @@ public function request(
         string $method,
         string $uri,
         array $attributes = []
-    ): array|string|null {
+    ): \Traversable|array|string|null {
         $params = $attributes['params'] ?? [];
         $body = $attributes['body'] ?? null;
         $options = $attributes['options'] ?? [];
diff --git a/src/OpenSearch/HttpTransport.php b/src/OpenSearch/HttpTransport.php
index 676fce4f..1802b080 100644
--- a/src/OpenSearch/HttpTransport.php
+++ b/src/OpenSearch/HttpTransport.php
@@ -36,7 +36,7 @@ public function sendRequest(
         array $params = [],
         mixed $body = null,
         array $headers = [],
-    ): array|string|null {
+    ): \Traversable|array|string|null {
         $request = $this->createRequest($method, $uri, $params, $body, $headers);
         $response = $this->client->sendRequest($request);
         $statusCode = $response->getStatusCode();
diff --git a/src/OpenSearch/LegacyTransportWrapper.php b/src/OpenSearch/LegacyTransportWrapper.php
index 7335a4d8..73167dca 100644
--- a/src/OpenSearch/LegacyTransportWrapper.php
+++ b/src/OpenSearch/LegacyTransportWrapper.php
@@ -28,13 +28,10 @@ public function sendRequest(
         array $params = [],
         mixed $body = null,
         array $headers = [],
-    ): array|string|null {
-        $promise = $this->transport->performRequest($method, $uri, $params, $body);
-        $futureArray = $this->transport->resultOrFuture($promise);
-        if ($futureArray instanceof FutureArrayInterface) {
-            return $futureArray->wait();
-        }
-        return $futureArray;
+    ): \Traversable|array|string|null {
+        $promise = $this->transport->performRequest($method, $uri, $params, $body, $headers);
+
+        return $this->transport->resultOrFuture($promise, $headers);
     }
 
 }
diff --git a/src/OpenSearch/TransportInterface.php b/src/OpenSearch/TransportInterface.php
index c2f432d3..adc16965 100644
--- a/src/OpenSearch/TransportInterface.php
+++ b/src/OpenSearch/TransportInterface.php
@@ -23,6 +23,6 @@ public function sendRequest(
         array $params = [],
         string|array|null $body = null,
         array $headers = [],
-    ): array|string|null;
+    ): \Traversable|array|string|null;
 
 }