diff --git a/packages/flutter_driver/lib/src/driver.dart b/packages/flutter_driver/lib/src/driver.dart
index 03d8bd61ad2..41448bfa874 100644
--- a/packages/flutter_driver/lib/src/driver.dart
+++ b/packages/flutter_driver/lib/src/driver.dart
@@ -208,7 +208,8 @@ class FlutterDriver {
       });
     }
 
-    // Waits for a signal from the VM service that the extension is registered
+    /// Waits for a signal from the VM service that the extension is registered.
+    /// Returns [_kFlutterExtensionMethod]
     Future<String> waitForServiceExtension() {
       return isolate.onExtensionAdded.firstWhere((String extension) {
         return extension == _kFlutterExtensionMethod;