diff --git a/src/pjson.ts b/src/pjson.ts
index b3fbb1de..e0b8e6a0 100644
--- a/src/pjson.ts
+++ b/src/pjson.ts
@@ -18,6 +18,7 @@ export namespace PJSON {
       commands?: string;
       plugins?: string[];
       devPlugins?: string[];
+      helpClass?: string;
       aliases?: { [name: string]: string | null };
       repositoryPrefix?: string;
       update: {