diff --git a/backend/src/index.ts b/backend/src/index.ts
index cc15439..614e27b 100644
--- a/backend/src/index.ts
+++ b/backend/src/index.ts
@@ -1,13 +1,30 @@
 import { Hono } from "hono";
 import { validator } from "hono/validator";
 
+let canConnectBridgeServer: boolean = true
+try {
+    await Bun.connect({
+        hostname: "localhost",
+        port: 8081,
+        socket: {
+            data: () => { },
+        },
+    })
+} catch (e) {
+    canConnectBridgeServer = false
+}
+
+if (!canConnectBridgeServer) {
+    console.log("Connect to bridge: localhost:8081 failed");
+    process.exit(1)
+}
+
 const appTmp = new Hono()
 const app = appTmp.basePath("/watermark")
-
 /**
  * param: image: 图片大小必须<=10MB
  * param: payload: 必须是长度<=8的字母大小写或数字组合
- * param: strength: 取值>=0,一般取值0~1.5
+ * param: strength: 取值0~100,一般取值0~1.5
  * param: outputType: 输出的文件类型，只允许 jpeg | png
  */
 app.post("/encode",