diff --git a/source/_docs/automation/templating.markdown b/source/_docs/automation/templating.markdown
index ad5b5ac5309..daf42cb408a 100644
--- a/source/_docs/automation/templating.markdown
+++ b/source/_docs/automation/templating.markdown
@@ -22,7 +22,7 @@ The following describes trigger data associated with all platforms.
 | Template variable | Data |
 | ---- | ---- |
 | `trigger.id` | Optional trigger `id`, or index of the trigger.
-| `trigger.idx` | Index of the trigger.
+| `trigger.idx` | Index of the trigger. (The first trigger idx is `0`.)
 
 ### Calendar