diff --git a/scripts/generate_road_colours.py b/scripts/generate_road_colours.py
index 754a6900d7..9003a52e49 100755
--- a/scripts/generate_road_colours.py
+++ b/scripts/generate_road_colours.py
@@ -1,5 +1,7 @@
 #!/usr/bin/env python2
 
+# Generates a set of highway colors to be stored in road-colors-generated.mss.
+
 from colormath.color_conversions import convert_color
 from colormath.color_objects import LabColor, LCHabColor, sRGBColor
 from colormath.color_diff import delta_e_cie2000