diff --git a/tools/cli/internal/openapi/filter/sunset.go b/tools/cli/internal/openapi/filter/sunset.go
index ae13930f3b..2f11c8f854 100644
--- a/tools/cli/internal/openapi/filter/sunset.go
+++ b/tools/cli/internal/openapi/filter/sunset.go
@@ -15,6 +15,7 @@
 package filter
 
 import (
+	"maps"
 	"strings"
 
 	"github.com/getkin/kin-openapi/openapi3"
@@ -55,12 +56,9 @@ func applyOnOperation(op *openapi3.Operation) {
 		}
 
 		for _, content := range response.Value.Content {
-			if v, ok := content.Extensions["x-sunset"]; ok {
-				if v != sunsetToBeDecided {
-					continue
-				}
-				delete(content.Extensions, "x-sunset")
-			}
+			maps.DeleteFunc(content.Extensions, func(_ string, v any) bool {
+				return v == sunsetToBeDecided
+			})
 		}
 	}
 }
diff --git a/tools/cli/internal/openapi/filter/sunset_test.go b/tools/cli/internal/openapi/filter/sunset_test.go
index 3ef1e67c23..049c7c7ec0 100644
--- a/tools/cli/internal/openapi/filter/sunset_test.go
+++ b/tools/cli/internal/openapi/filter/sunset_test.go
@@ -326,6 +326,7 @@ func TestSunsetFilter_Apply(t *testing.T) {
 
 	for _, tc := range testCases {
 		t.Run(tc.name, func(t *testing.T) {
+			t.Parallel()
 			f := &SunsetFilter{
 				oas: tc.initSpec,
 			}