> ## Documentation Index
> Fetch the complete documentation index at: https://ngrok.com/docs/llms.txt
> Use this file to discover all available pages before exploring further.

# Error 3806

## ERR\_NGROK\_3806

Expression `EXPRESSION` must return an AIModel or \[]AIModel, got `ACTUALTYPE`. See [https://ngrok.com/docs/ai-gateway/reference/error-codes#err\_ngrok\_3806](https://ngrok.com/docs/ai-gateway/reference/error-codes#err_ngrok_3806) for more information.

## Further help

If you're having trouble resolving this error, please reach out to [support@ngrok.com](mailto:support@ngrok.com?subject=Help%20with%20ERR_NGROK_3806)