wait for the cloudflared tunnel to fully start before exposing its URL

package.json

@@ -1,7 +1,7 @@
 {
   "name": "gerbil",
   "productName": "Gerbil",
-  "version": "1.16.2",
+  "version": "1.16.3",
   "description": "Run Large Language Models locally",
   "main": "out/main/index.js",
   "homepage": "./",
@@ -67,7 +67,7 @@
   "devDependencies": {
     "@eslint/js": "^9.39.2",
     "@types/mime-types": "^3.0.1",
-    "@types/node": "^25.0.1",
+    "@types/node": "^25.0.2",
     "@types/react": "^19.2.7",
     "@types/react-dom": "^19.2.3",
     "@types/yauzl": "^2.10.3",

src/components/screens/Launch/NetworkTab.tsx

@@ -92,7 +92,7 @@ export const NetworkTab = () => {
               checked={remotetunnel}
               onChange={setRemotetunnel}
               label="Remote Tunnel"
-              tooltip="Creates a trycloudflare tunnel. Allows you to access your server from other devices over an internet URL."
+              tooltip="Creates a cloudflare tunnel. Allows you to access your server from other devices over an internet URL."
             />
 
             <CheckboxWithTooltip

src/main/modules/koboldcpp/tunnel.ts

@@ -81,6 +81,25 @@ const getTunnelTarget = (frontendPreference: FrontendPreference) => {
   }
 };
 
+const waitForBackend = async (url: string, timeoutMs = 30000) => {
+  const startTime = Date.now();
+
+  while (Date.now() - startTime < timeoutMs) {
+    try {
+      const response = await fetch(url, {
+        method: 'HEAD',
+        signal: AbortSignal.timeout(2000),
+      });
+      if (response.ok) {
+        return true;
+      }
+    } catch {}
+    await new Promise((resolve) => setTimeout(resolve, 500));
+  }
+
+  return false;
+};
+
 export const startTunnel = async (
   frontendPreference: FrontendPreference = 'koboldcpp'
 ) => {
@@ -89,6 +108,17 @@ export const startTunnel = async (
   }
 
   try {
+    const tunnelTarget = getTunnelTarget(frontendPreference);
+
+    sendKoboldOutput('Waiting for backend to be ready...');
+    const backendReady = await waitForBackend(tunnelTarget);
+
+    if (!backendReady) {
+      throw new Error(
+        'Backend not ready after 30 seconds. Start your backend first before enabling tunnel.'
+      );
+    }
+
     sendKoboldOutput('Starting Cloudflare tunnel...');
 
     const bin = getCloudflaredBin();
@@ -101,7 +131,6 @@ export const startTunnel = async (
       await downloadCloudflared(bin);
     }
 
-    const tunnelTarget = getTunnelTarget(frontendPreference);
     const tunnel = execa(bin, [
       'tunnel',
       '--url',
@@ -163,6 +192,8 @@ export const startTunnel = async (
       });
     });
 
+    await new Promise((resolve) => setTimeout(resolve, 3000));
+
     tunnelUrl = url;
     sendKoboldOutput(`Tunnel ready at ${tunnelUrl}`);
     sendToRenderer('tunnel-url-changed', tunnelUrl);

yarn.lock

@@ -1401,12 +1401,12 @@ __metadata:
   languageName: node
   linkType: hard
 
-"@types/node@npm:*, @types/node@npm:^25.0.1":
-  version: 25.0.1
-  resolution: "@types/node@npm:25.0.1"
+"@types/node@npm:*, @types/node@npm:^25.0.2":
+  version: 25.0.2
+  resolution: "@types/node@npm:25.0.2"
   dependencies:
     undici-types: "npm:~7.16.0"
-  checksum: 10c0/1d5ca9f240d0cf8e43d5281c0e6ee96fb22d37dc2e5ef52c6ca71de47957a6128e124990cedf5b14c03d0250737bd78ad370d93bcf1729a75ca4e54384fdd51a
+  checksum: 10c0/12c4044bf2e46ba3d313ddf6256ee3c88e336a62d129fe788eeab8ff2631b3df51eb31ade4cdc04552fbe51e285f0663c49b60c78acd31da2b9f2c86a84347e3
   languageName: node
   linkType: hard
 
@@ -3860,7 +3860,7 @@ __metadata:
     "@mantine/core": "npm:^8.3.10"
     "@mantine/hooks": "npm:^8.3.10"
     "@types/mime-types": "npm:^3.0.1"
-    "@types/node": "npm:^25.0.1"
+    "@types/node": "npm:^25.0.2"
     "@types/react": "npm:^19.2.7"
     "@types/react-dom": "npm:^19.2.3"
     "@types/yauzl": "npm:^2.10.3"