diff --git a/UPGRADE-3.0.md b/UPGRADE-3.0.md
index 2c2f87f..e36f33e 100644
--- a/UPGRADE-3.0.md
+++ b/UPGRADE-3.0.md
@@ -81,7 +81,7 @@ class SwaggerDocblockConvertCommand extends ContainerAwareCommand
      *     summary="'.$this->escapeQuotes($apiDoc->getDescription()).'"';
 
         foreach ($apiDoc->getFilters() as $name => $parameter) {
-            $description = array_key_exists('description', $parameter)
+            $description = array_key_exists('description', $parameter) && null !== $parameter['description']
                 ? $this->escapeQuotes($parameter['description'])
                 : 'todo';