diff --git a/docs/src/reference/types.md b/docs/src/reference/types.md
index 31b41598f..aabe88510 100644
--- a/docs/src/reference/types.md
+++ b/docs/src/reference/types.md
@@ -153,16 +153,20 @@ Lightens a color.
 
 - amount: ratio (positional, required)
   The factor to lighten the color by.
+- returns: color
 
 ### darken()
 Darkens a color.
 
 - amount: ratio (positional, required)
   The factor to darken the color by.
+- returns: color
 
 ### negate()
 Produces the negative of the color.
 
+- returns: color
+
 # Symbol
 A Unicode symbol.