diff --git a/packages/hydrooj/src/handler/api.ts b/packages/hydrooj/src/handler/api.ts
index 8ec815625..8ac678bf3 100644
--- a/packages/hydrooj/src/handler/api.ts
+++ b/packages/hydrooj/src/handler/api.ts
@@ -94,6 +94,7 @@ export function rebuild() {
 }
 
 class ApiHandler extends Handler {
+    category = '#api';
     noCheckPermView = true;
 
     query(q: string, variables: any) {
diff --git a/packages/hydrooj/src/plugin-api.ts b/packages/hydrooj/src/plugin-api.ts
index 7aac4e66c..1181e7066 100644
--- a/packages/hydrooj/src/plugin-api.ts
+++ b/packages/hydrooj/src/plugin-api.ts
@@ -11,6 +11,7 @@ export * as BlogModel from './model/blog';
 export * as SettingModel from './model/setting';
 export * as DiscussionModel from './model/discussion';
 export * as DocumentModel from './model/document';
+export { DocType } from './model/document';
 export * as BuiltinModel from './model/builtin';
 export * as ContestModel from './model/contest';
 export { default as TokenModel } from './model/token';
@@ -26,12 +27,14 @@ export { default as StorageModel } from './model/storage';
 export { default as TaskModel } from './model/task';
 export * from './model/builtin';
 export * as JudgeHandler from './handler/judge';
+export { registerResolver, registerValue, registerUnion } from './handler/api';
 export { postJudge } from './handler/judge';
 export { Collections } from './service/db';
 // export { Collections } from './interface';
 export { Service, Context } from './context';
 export { buildContent } from './lib/content';
 export * as validator from './lib/validator';
+export { default as avatar } from './lib/avatar';
 export { default as rank } from './lib/rank';
 export { default as paginate } from './lib/paginate';
 export * from './service/decorators';