diff --git a/scada-common/mqueue.lua b/scada-common/mqueue.lua
index 30c21e8..8069ecb 100644
--- a/scada-common/mqueue.lua
+++ b/scada-common/mqueue.lua
@@ -24,6 +24,10 @@ mqueue.new = function ()
     ---@field qtype TYPE
     ---@field message any
 
+    ---@class queue_data
+    ---@field key any
+    ---@field val any
+
     ---@class mqueue
     local public = {}