diff --git a/DEVELOP.md b/DEVELOP.md
new file mode 100644
index 0000000..16a20d3
--- /dev/null
+++ b/DEVELOP.md
@@ -0,0 +1,15 @@
+# Development Guide
+
+1. install http-server to enable debug at local.
+
+```bash
+npm install -g http-server
+```
+2. run `npm install` to build the project.
+3. in `./` folder, use `http-server` to start server
+4. open the following link to debug.
+   please note, the server address should be checked in the source code of `xxx.html`!
+```
+http://127.0.0.1:8080/test/ws.html
+http://127.0.0.1:8080/test/http.html
+```
\ No newline at end of file
diff --git a/package.json b/package.json
index 327a0b6..7490d08 100644
--- a/package.json
+++ b/package.json
@@ -1,6 +1,6 @@
 {
   "name": "@bdware/bdcontract-sdk",
-  "version": "0.3.0-alpha.14",
+  "version": "0.3.0-alpha.15",
   "description": "BDContract SDK for Node.js and browsers",
   "license": "MIT",
   "keywords": [
@@ -47,5 +47,14 @@
     "shx": "^0.3.4",
     "sucrase": "^3.25.0",
     "typescript": "^4.8.2"
-  }
+  },
+  "directories": {
+    "lib": "lib",
+    "test": "test"
+  },
+  "repository": {
+    "type": "git",
+    "url": "git@gitea.internetapi.cn:bdware/bdcontract-sdk-javascript.git"
+  },
+  "author": "caihq@pku.edu.cn"
 }
diff --git a/test/ws.html b/test/ws.html
index 80f04aa..086b271 100644
--- a/test/ws.html
+++ b/test/ws.html
@@ -10,18 +10,20 @@
         document.write(`${string}\n\n`)
       }
 
-      const url = 'ws://39.104.201.40:18010/SCIDE/SCExecutor'
+      const url = 'ws://127.0.0.1:18000/SCIDE/SCExecutor'
 
       const client = new bdcontract.WsClient(
         url,
         (ev) => {
-          console.log(JSON.stringify(ev))
+          console.log("onOpen:"+JSON.stringify(ev))
+          invokeContract()
         },
         (ev, ws) => {
           console.log(ev.data)
         },
       )
-      setTimeout(async () => {
+     function invokeContract(){
+     setTimeout(async () => {
         const status = client.status()
         console.log(status)
         try {
@@ -42,6 +44,8 @@
           print(JSON.stringify(data))
         }
       }, 1000)
+     }
+
     </script>
     <link rel="icon" type="image/svg+xml" href="favicon.svg"/>
     <meta name="viewport" content="width=device-width, initial-scale=1.0"/>