diff --git a/index.md b/index.md
index 4b207ef..d13dde9 100644
--- a/index.md
+++ b/index.md
@@ -234,7 +234,8 @@ prometheus_log_level: error
 #### Default value
 
 ```YAML
-prometheus_packages: []
+prometheus_packages:
+  - tar
 ```
 
 ### prometheus_read_only_dirs