diff --git a/pkg/apis/tenant/v1alpha2/register.go b/pkg/apis/tenant/v1alpha2/register.go
index e54992c17..7e148b30e 100644
--- a/pkg/apis/tenant/v1alpha2/register.go
+++ b/pkg/apis/tenant/v1alpha2/register.go
@@ -151,7 +151,7 @@ func addWebService(c *restful.Container) error {
 	ws.Route(ws.GET("/logs").
 		To(tenant.LogQuery).
 		Doc("Query cluster-level logs in a multi-tenants environment").
-		Param(ws.QueryParameter("operation", "Query type. This can be one of three types: query (for querying logs), statistics (for retrieving statistical data), and histogram (for displaying log count by time interval).").DataType("string").Required(true)).
+		Param(ws.QueryParameter("operation", "Query type. This can be one of three types: query (for querying logs), statistics (for retrieving statistical data), and histogram (for displaying log count by time interval). Defaults to query.").DefaultValue("query").DataType("string").Required(false)).
 		Param(ws.QueryParameter("workspaces", "A comma-separated list of workspaces. This field restricts the query to specified workspaces. For example, the following filter matches the workspace my-ws and demo-ws: `my-ws,demo-ws`").DataType("string").Required(false)).
 		Param(ws.QueryParameter("workspace_query", "A comma-separated list of keywords. Differing from **workspaces**, this field performs fuzzy matching on workspaces. For example, the following value limits the query to workspaces whose name contains the word my(My,MY,...) *OR* demo(Demo,DemO,...): `my,demo`.").DataType("string").Required(false)).
 		Param(ws.QueryParameter("namespaces", "A comma-separated list of namespaces. This field restricts the query to specified namespaces. For example, the following filter matches the namespace my-ns and demo-ns: `my-ns,demo-ns`").DataType("string").Required(false)).