diff --git a/packages/redux-devtools-chart-monitor/src/actions.ts b/packages/redux-devtools-chart-monitor/src/actions.ts
index 0eefa3a9..062215ed 100644
--- a/packages/redux-devtools-chart-monitor/src/actions.ts
+++ b/packages/redux-devtools-chart-monitor/src/actions.ts
@@ -1,2 +1,6 @@
 export const TOGGLE_VISIBILITY =
   '@@redux-devtools-log-monitor/TOGGLE_VISIBILITY';
+interface ToggleVisibilityAction {
+  type: typeof TOGGLE_VISIBILITY;
+}
+export type ChartMonitorAction = ToggleVisibilityAction;