Merge pull request #5 from geelen/add-vpn-warning

Add VPN warning and debugging guidance to README

README.md

@@ -20,3 +20,37 @@ E.g: Claude Desktop or Windsurf
 Cursor:
 
 ![image](https://github.com/user-attachments/assets/14338bfa-a779-4e8a-a477-71f72cc5d99d)
+
+
+## Debugging
+
+### Check your Node version
+
+Make sure that the version of Node you have installed is [16 or higher](https://modelcontextprotocol.io/quickstart/server).
+
+### Restart Claude
+
+When modifying `claude_desktop_config.json` it can helpful to completely restart Claude
+
+### VPN Certs
+
+You may run into issues if you are behind a VPN, you can try setting the `NODE_EXTRA_CA_CERTS`
+environment variable to point to the CA certificate file. If using `claude_desktop_config.json`,
+this might look like:
+
+```json
+{
+ "mcpServers": {
+    "remote-example": {
+      "command": "npx",
+      "args": [
+        "mcp-remote",
+        "https://remote.mcp.server/sse"
+      ],
+      "env": {
+        "NODE_EXTRA_CA_CERTS": "{your CA certificate file path}.pem"
+      }
+    }
+  }
+}
+```

package.json

@@ -18,6 +18,7 @@
     }
   },
   "scripts": {
+    "dev": "tsup --watch",
     "build": "tsup",
     "check": "prettier --check . && tsc"
   },

src/cli/proxy.ts

@@ -63,6 +63,28 @@ async function runProxy(serverUrl: string, callbackPort: number) {
     setupSignalHandlers(cleanup)
   } catch (error) {
     console.error('Fatal error:', error)
+    if (error instanceof Error && error.message.includes('self-signed certificate in certificate chain')) {
+      console.error(`You may be behind a VPN!
+
+If you are behind a VPN, you can try setting the NODE_EXTRA_CA_CERTS environment variable to point
+to the CA certificate file. If using claude_desktop_config.json, this might look like:
+
+{
+  "mcpServers": {
+    "\${mcpServerName}": {
+      "command": "npx",
+      "args": [
+        "mcp-remote",
+        "https://remote.mcp.server/sse"
+      ],
+      "env": {
+        "NODE_EXTRA_CA_CERTS": "\${your CA certificate file path}.pem"
+      }
+    }
+  }
+}
+        `)
+    }
     server.close()
     process.exit(1)
   }