diff --git a/runtime/lua/vim/_extui/shared.lua b/runtime/lua/vim/_extui/shared.lua
index eac8ff5e38..5ac4cb55d4 100644
--- a/runtime/lua/vim/_extui/shared.lua
+++ b/runtime/lua/vim/_extui/shared.lua
@@ -17,6 +17,7 @@ local M = {
     },
   },
 }
+--- @type vim.api.keyset.win_config
 local wincfg = { -- Default cfg for nvim_open_win().
   relative = 'laststatus',
   style = 'minimal',
diff --git a/runtime/lua/vim/_meta/api.lua b/runtime/lua/vim/_meta/api.lua
index 54fd1c0d01..61e4a28704 100644
--- a/runtime/lua/vim/_meta/api.lua
+++ b/runtime/lua/vim/_meta/api.lua
@@ -2415,7 +2415,7 @@ function vim.api.nvim_win_get_buf(window) end
 --- `relative` is empty for normal windows.
 ---
 --- @param window integer `window-ID`, or 0 for current window
---- @return vim.api.keyset.win_config # Map defining the window configuration, see |nvim_open_win()|
+--- @return vim.api.keyset.win_config_ret # Map defining the window configuration, see |nvim_open_win()|
 function vim.api.nvim_win_get_config(window) end
 
 --- Gets the (1,0)-indexed, buffer-relative cursor position for a given window
diff --git a/runtime/lua/vim/_meta/api_keysets_extra.lua b/runtime/lua/vim/_meta/api_keysets_extra.lua
index a3a444ae98..42bb7ffaea 100644
--- a/runtime/lua/vim/_meta/api_keysets_extra.lua
+++ b/runtime/lua/vim/_meta/api_keysets_extra.lua
@@ -247,3 +247,24 @@ error('Cannot require a meta file')
 --- @field fill integer
 --- @field end_row integer
 --- @field end_vcol integer
+
+-- Inherit from vim.api.keyset.win_config so this type can be passed to nvim_open_win().
+-- Because of this we only need to define the fields with different types (nil or non-nil).
+
+--- @class vim.api.keyset.win_config_ret : vim.api.keyset.win_config
+--- @field focusable boolean
+--- @field external boolean
+--- @field hide boolean
+--- @field mouse boolean
+--- @field width integer
+--- @field height integer
+--- @field relative 'cursor'|'editor'|'laststatus'|'mouse'|'tabline'|'win'
+---
+--- @field noautocmd nil
+--- @field title nil
+--- @field title_pos nil
+--- @field footer nil
+--- @field footer_pos nil
+--- @field style nil
+--- @field fixed nil
+--- @field vertical nil
diff --git a/src/gen/gen_eval_files.lua b/src/gen/gen_eval_files.lua
index 4ac4d754da..5ff07a0f53 100755
--- a/src/gen/gen_eval_files.lua
+++ b/src/gen/gen_eval_files.lua
@@ -24,6 +24,10 @@ local TEXT_WIDTH = 78
 --- @field remote boolean
 --- @field since integer
 
+local LUA_API_RETURN_OVERRIDES = {
+  nvim_win_get_config = 'vim.api.keyset.win_config_ret',
+}
+
 local LUA_META_HEADER = {
   '--- @meta _',
   '-- THIS FILE IS GENERATED',
@@ -306,7 +310,8 @@ local function render_api_meta(_f, fun, write)
 
   if fun.returns ~= 'nil' then
     local ret_desc = fun.returns_desc and ' # ' .. fun.returns_desc or ''
-    write(util.prefix_lines('--- ', '@return ' .. fun.returns .. ret_desc))
+    local ret = LUA_API_RETURN_OVERRIDES[fun.name] or fun.returns
+    write(util.prefix_lines('--- ', '@return ' .. ret .. ret_desc))
   end
   local param_str = table.concat(param_names, ', ')