diff --git a/data/scripts/game.lua b/data/scripts/game.lua
index 0f332c0..cf909c8 100644
--- a/data/scripts/game.lua
+++ b/data/scripts/game.lua
@@ -4,9 +4,11 @@ local Vector3 = require "types.vector3"
 local List = require "types.list"
 
 local Feed = require "classes.feed"
+---@type List
 local feed = List()
 
 local Duck = require "classes.duck"
+---@type List
 local ducks = List()
 
 local function create_feed(position, direction)
diff --git a/data/scripts/types/list.lua b/data/scripts/types/list.lua
index 3a06476..9529561 100644
--- a/data/scripts/types/list.lua
+++ b/data/scripts/types/list.lua
@@ -154,7 +154,7 @@ function List:shuffled()
 end
 
 ---Returns a sorted copy of this list.
----@param f? fun(a: any, b: any)
+---@param f? fun(a: any, b: any): boolean
 ---@return List
 function List:sorted(f)
   local list = self:copy()