diff --git a/src/SlackLogger.php b/src/SlackLogger.php
index a3a4eb7..0037fe7 100644
--- a/src/SlackLogger.php
+++ b/src/SlackLogger.php
@@ -14,7 +14,7 @@
 class SlackLogger extends Logger
 {
 
-	/** @var */
+	/** @var string */
 	private $slackUrl;
 
 	/** @var string */