diff --git a/tools/etcd-dump-metrics/main.go b/tools/etcd-dump-metrics/main.go
index a2ff77c31..0648c8b2b 100644
--- a/tools/etcd-dump-metrics/main.go
+++ b/tools/etcd-dump-metrics/main.go
@@ -12,6 +12,7 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
+// etcd-dump-metrics automates etcd Prometheus metrics documentation.
 package main
 
 import (