diff --git a/docker-compose.yml b/docker-compose.yml
index 3d9d788e..ac9124b0 100644
--- a/docker-compose.yml
+++ b/docker-compose.yml
@@ -544,7 +544,7 @@ services:
       X_AUTHELIA_CONFIG_FILTERS: template
     expose:
       - 9091
-      - 9959
+      - 9959 # Metrics port for Prometheus
     image: authelia/authelia:master@sha256:30c4d60e09b5d55ff90372e5f272fd590076057e9144441a443b0bc21e1ff016
     labels:
       homepage.group: Privacy/Security