diff --git a/index.d.ts b/index.d.ts
index 9165925..2fb217f 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -1,5 +1,13 @@
 import { Application, Context } from 'egg';
 import { MockMate } from 'mm';
+import { Test } from 'supertest';
+
+interface EggTest extends Test {
+  unexpectHeader(name: string, b?: Function): EggTest;
+  expectHeader(name: string, b?: Function): EggTest;
+}
+
+type Methods = 'get' | 'post' | 'delete' | 'del' | 'put' | 'head' | 'options' | 'patch' | 'trace' | 'connect';
 
 export interface BaseMockApplication<T, C> extends Application { // tslint:disble-line
   ready(): Promise<void>;
@@ -42,7 +50,11 @@ export interface BaseMockApplication<T, C> extends Application { // tslint:disbl
   /**
    * http request helper
    */
-  httpRequest(): any;
+  httpRequest(): {
+    [key in Methods]: (url: string) => EggTest;
+  } & {
+    [key: string]: (url: string) => EggTest;
+  };
 }
 
 interface ResultObject {
diff --git a/package.json b/package.json
index 94840ef..b0a6ec2 100644
--- a/package.json
+++ b/package.json
@@ -26,6 +26,7 @@
   },
   "dependencies": {
     "@types/power-assert": "^1.5.0",
+    "@types/supertest": "^2.0.7",
     "await-event": "^2.1.0",
     "co": "^4.6.0",
     "coffee": "^5.2.1",
@@ -41,9 +42,9 @@
     "merge-descriptors": "^1.0.1",
     "methods": "^1.1.2",
     "mm": "^2.5.0",
+    "mz-modules": "^2.1.0",
     "power-assert": "^1.6.1",
     "supertest": "^4.0.2",
-    "mz-modules": "^2.1.0",
     "urllib": "^2.33.3"
   },
   "devDependencies": {