diff --git a/def/Object.d.lua b/def/Object.d.lua
index 17ee45a..112e51a 100644
--- a/def/Object.d.lua
+++ b/def/Object.d.lua
@@ -21,4 +21,9 @@ function Object:extend() end
 ---@param mixin table
 function Object:implement(mixin) end
 
+---Checks if object is of a specific type
+---@param object Object
+---@return boolean
+function Object:is(object) end
+
 return Object