diff --git a/changelogs/fragments/doc_debug_var.yml b/changelogs/fragments/doc_debug_var.yml
new file mode 100644
index 00000000000..1318b69a264
--- /dev/null
+++ b/changelogs/fragments/doc_debug_var.yml
@@ -0,0 +1,2 @@
+bugfixes:
+    - document debug's var already having implicit moustaches
diff --git a/lib/ansible/modules/utilities/logic/debug.py b/lib/ansible/modules/utilities/logic/debug.py
index 480e088fc49..6be2607cf01 100644
--- a/lib/ansible/modules/utilities/logic/debug.py
+++ b/lib/ansible/modules/utilities/logic/debug.py
@@ -33,6 +33,8 @@ options:
   var:
     description:
       - A variable name to debug.  Mutually exclusive with the 'msg' option.
+      - Be aware that this option already runs in Jinja2 context and has an implicit ``{{ }}`` wrapping,
+        so you should not be using Jinja2 delimiters unless you are looking for double interpolation.
   verbosity:
     description:
       - A number that controls when the debug is run, if you set to 3 it will only run debug when -vvv or above