diff --git a/src/Composer/Util/SyncHelper.php b/src/Composer/Util/SyncHelper.php
index 9b230781f..964a78cd1 100644
--- a/src/Composer/Util/SyncHelper.php
+++ b/src/Composer/Util/SyncHelper.php
@@ -14,7 +14,9 @@ class SyncHelper
      * This executes all the required steps and waits for promises to complete
      *
      * @param Loop                  $loop        Loop instance which you can get from $composer->getLoop()
-     * @param string                $path        the installation path
+     * @param DownloaderInterface   $downloader  Downloader instance you can get from $composer->getDownloadManager()->getDownloader('zip') for example
+     * @param string                $path        the installation path for the package
+     * @param PackageInterface      $package     the package to install
      * @param PackageInterface|null $prevPackage the previous package if this is an update and not an initial installation
      */
     public static function downloadAndInstallPackageSync(Loop $loop, DownloaderInterface $downloader, $path, PackageInterface $package, PackageInterface $prevPackage = null)