diff --git a/cmd/options.go b/cmd/options.go
index f166d8fba..b8ff855f4 100644
--- a/cmd/options.go
+++ b/cmd/options.go
@@ -98,8 +98,8 @@ func WithLazyRefresh() Option {
 	}
 }
 
-// WithConnRefuseNotify configures the Proxy to start a goroutine and run the
-// given notify callback function in the event of a connection refuse.
+// WithConnRefuseNotify configures the Proxy to call the provided function when
+// a connection is refused. The notification function is run in a goroutine.
 func WithConnRefuseNotify(n func()) Option {
        return func(c *Command) {
                c.connRefuseNotify = n
diff --git a/internal/healthcheck/healthcheck_test.go b/internal/healthcheck/healthcheck_test.go
index b4729bb3f..bb86b72ea 100644
--- a/internal/healthcheck/healthcheck_test.go
+++ b/internal/healthcheck/healthcheck_test.go
@@ -78,7 +78,7 @@ func newProxyWithParams(t *testing.T, maxConns uint64, dialer cloudsql.Dialer, i
 		Instances:      instances,
 		MaxConnections: maxConns,
 	}
-	p, err := proxy.NewClient(context.Background(), dialer, logger, c)
+	p, err := proxy.NewClient(context.Background(), dialer, logger, c, nil)
 	if err != nil {
 		t.Fatalf("proxy.NewClient: %v", err)
 	}