diff --git a/gen-go-code.py b/gen-go-code.py
index d875dc71e..3af2730ec 100755
--- a/gen-go-code.py
+++ b/gen-go-code.py
@@ -246,7 +246,7 @@ def update_at_commands() -> None:
             os.remove(dest)
         with open(dest, 'w') as f:
             f.write(code)
-    print('\x1b[31mTODO\x1b[m: test set_font_size, send_text, env, scroll_window', file=sys.stderr)
+    print('\x1b[31mTODO\x1b[m: test send_text, env, scroll_window', file=sys.stderr)
 
 
 def main() -> None:
diff --git a/kitty/rc/set_font_size.py b/kitty/rc/set_font_size.py
index 6b41f35e3..649059a93 100644
--- a/kitty/rc/set_font_size.py
+++ b/kitty/rc/set_font_size.py
@@ -26,9 +26,10 @@ class SetFontSize(RemoteCommand):
         ' must have the same font size. A value of zero'
         ' resets the font size to default. Prefixing the value'
         ' with a :code:`+` or :code:`-` increments the font size by the specified'
-        ' amount.'
+        ' amount. Use -- before using - to have it not mistaken for a option. For example:'
+        ' kitty @ set-font-size -- -2'
     )
-    args = RemoteCommand.Args(spec='FONT_SIZE', count=1, special_parse='+increment_op:parse_set_font_size(args[0], io_data)', json_field='size')
+    args = RemoteCommand.Args(spec='FONT_SIZE', count=1, special_parse='+increment_op:parse_set_font_size(args[0], &payload)', json_field='size')
     options_spec = '''\
 --all -a
 type=bool-set
diff --git a/tools/cmd/at/set_font_size.go b/tools/cmd/at/set_font_size.go
index 340970b94..a307dc80f 100644
--- a/tools/cmd/at/set_font_size.go
+++ b/tools/cmd/at/set_font_size.go
@@ -6,16 +6,15 @@ import (
 	"strconv"
 )
 
-func parse_set_font_size(arg string, io_data *rc_io_data) error {
-	payload := io_data.rc.Payload.(set_font_size_json_type)
+func parse_set_font_size(arg string, payload *set_font_size_json_type) error {
 	if len(arg) > 0 && (arg[0] == '+' || arg[0] == '-') {
 		payload.Increment_op = arg[:1]
+		arg = arg[1:]
 	}
 	val, err := strconv.ParseFloat(arg, 64)
 	if err != nil {
 		return err
 	}
 	payload.Size = val
-	io_data.rc.Payload = payload
 	return nil
 }