ERR_NGROK_394: Each tunnel must specify either a protocol or labels, but neither was set - ngrok documentation

What does ERR_NGROK_394 mean?

ngrok returns ERR_NGROK_394 with this message:

Each tunnel must specify either a protocol or labels, but neither was set.

Troubleshoot ERR_NGROK_394 with your AI agent. Connect it to the ngrok MCP server, then ask what caused the error and how to fix it.

Where can I get more help with ERR_NGROK_394?

Email support@ngrok.com and include the error code.