diff --git a/express-openapi/express-openapi-tests.ts b/express-openapi/express-openapi-tests.ts
index ca79c90ed..226f97939 100644
--- a/express-openapi/express-openapi-tests.ts
+++ b/express-openapi/express-openapi-tests.ts
@@ -13,8 +13,43 @@ api = openapi.initialize({
     routes: './api-routes'
 });
 
-app.use(function (err, req, res, next) {
-    res.status(err.status).json(err);
-});
+app.listen(3000);
 
-app.listen(3000);
\ No newline at end of file
+// "./api-routes/user/{id}.ts"
+export var get: openapi.Operation = (req, res, next) => {
+};
+
+export var post: openapi.Operation = [(req, res, next) => {}];
+
+export var parameters = [
+    {
+        name: 'id',
+        in: 'path',
+        type: 'string'
+    }
+];
+
+get.apiDoc = {
+    description: 'get user information',
+    operationId: 'getUser',
+    parameters: [
+        {
+            name: 'includeDetail',
+            in: 'query',
+            type: 'boolean'
+        }
+    ],
+    responses: {
+        default: {$ref: '#/definitions/error'}
+    },
+    "x-some-vendor-property": {}
+};
+
+post.apiDoc = {
+    description: 'post to user',
+    operationId: 'postToUser',
+    responses: {
+        default: {$ref: '#/definitions/error'}
+    },
+    "x-some-vendor-property": {}
+}
\ No newline at end of file
diff --git a/express-openapi/express-openapi.d.ts b/express-openapi/express-openapi.d.ts
index 633407ee1..a769cc7df 100644
--- a/express-openapi/express-openapi.d.ts
+++ b/express-openapi/express-openapi.d.ts
@@ -251,6 +251,28 @@ declare module "express-openapi" {
         routes: string
     }
 
+    export interface OperationFunction extends express.RequestHandler {
+        apiDoc?: OpenApi.OperationObject;
+    }
+
+    export interface OperationHandlerArray {
+        apiDoc?: OpenApi.OperationObject;
+        [index: number]: express.RequestHandler;
+    }
+
+    export type Operation = OperationFunction | OperationHandlerArray;
+
+    export interface PathModule {
+        parameters?: OpenApi.Parameters;
+        get?: Operation;
+        put?: Operation;
+        post?: Operation;
+        delete?: Operation;
+        patch?: Operation;
+        options?: Operation;
+        head?: Operation;
+    }
+
     interface IJsonSchema {
         id?: string
         $schema?: string