diff --git a/specification/web/resource-manager/Microsoft.Web/stable/2021-01-15/Certificates.json b/specification/web/resource-manager/Microsoft.Web/stable/2021-01-15/Certificates.json
index d13f0cb4be44..d378cc1e18b8 100644
--- a/specification/web/resource-manager/Microsoft.Web/stable/2021-01-15/Certificates.json
+++ b/specification/web/resource-manager/Microsoft.Web/stable/2021-01-15/Certificates.json
@@ -441,7 +441,7 @@
               "type": "string"
             },
             "domainValidationMethod": {
-              "description": "Method of domain validation for free cert",
+              "description": "Method of domain validation for free cert. Possible values include: 'CNameValidationValue', 'HttpTokenValidationValue'",
               "type": "string"
             }
           },