diff --git a/doc/user/project/integrations/webhook_events.md b/doc/user/project/integrations/webhook_events.md
index d05e9533d7df65b96b5d5a6f55851866729e90b3..e6bf766e17791d9f46d9f8b479d304e853930ae9 100644
--- a/doc/user/project/integrations/webhook_events.md
+++ b/doc/user/project/integrations/webhook_events.md
@@ -824,6 +824,11 @@ The available values for `object_attributes.action` in the payload are:
 - `unapproval`
 - `merge`
 
+The field `object_attributes.oldrev` is only available when there are actual code changes, like:
+
+- New code is pushed.
+- A [suggestion](../merge_requests/reviews/suggestions.md) is applied.
+
 Request header:
 
 ```plaintext