diff --git a/index.d.ts b/index.d.ts
index 9472cc1c..742d9348 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -161,12 +161,18 @@ export interface IValidation {
   [validation: string]: any
 }
 
-export interface AllowedResource {
+export interface ContentfulEntryResource {
   type: 'Contentful:Entry'
   source: string
   contentTypes: string[]
 }
 
+export interface ExternalResource {
+  type: string
+}
+
+export type AllowedResource = ContentfulEntryResource | ExternalResource
+
 export type WidgetSettingsValue = number | boolean | string | undefined
 
 export interface IEditorInterfaceOptions {