ERR_NGROK_210: The content type you specified CTYPE is not supported by the API

What does ERR_NGROK_210 mean?

ngrok returns ERR_NGROK_210 with this message:

The content type you specified <CTYPE> is not supported by the API. Check your API client implementation and see the list of supported content types: https://ngrok.com/docs/api#content-types

Troubleshoot ERR_NGROK_210 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_210?

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