diff --git a/kitty/options/definition.py b/kitty/options/definition.py
index d8371fe9c..413455f6f 100644
--- a/kitty/options/definition.py
+++ b/kitty/options/definition.py
@@ -140,6 +140,10 @@
 from Ø. Fira Code Retina also includes other discretionary features known as
 Stylistic Sets which have the tags :code:`ss01` through :code:`ss20`.
 
+For the exact syntax to use for individual features, see the
+:link:`Harfbuzz documentation
+<https://harfbuzz.github.io/harfbuzz-hb-common.html#hb-feature-from-string>`.
+
 Note that this code is indexed by PostScript name, and not the font
 family. This allows you to define very precise feature settings; e.g. you can
 disable a feature in the italic font but not in the regular font.