diff --git a/spec/schemas/cluster.health.yaml b/spec/schemas/cluster.health.yaml
index 1776ac780..aec20cc20 100644
--- a/spec/schemas/cluster.health.yaml
+++ b/spec/schemas/cluster.health.yaml
@@ -138,6 +138,7 @@ components:
         - status
         - unassigned_shards
     Level:
+      description: Controls the amount of detail included in the cluster health response.
       type: string
       enum:
         - awareness_attributes