"Raw_body_text" is an experimental feature that allows access to the raw response of an API call. Currently, it is only accessible via the API connector when the “include errors” or “include headers” checkbox is clicked in the API Connector.
Right now, we only allow using the raw_body_text when the response is wrapped since non-wrapped responses can be shallow types like text, so you couldn’t add other operators on top of it.
To resolve this, we recommend accessing the response data through the returned fields, instead of using the response's raw data – as this will give you more control over how the response data is handled.
For more information on the API Connector, check out our manual entry here.