If you configure a third-party REST API (Service Editor > TL script functions for external APIs), you can include a response header value as additional arguments in the response processing, but not the actual status code that the response provides.
You can handle individual status codes separately, but in "general" response processing you cannot determine which status code the response has:
Usually you have a positive response (e.g. status code 200) and a set of error codes (400, 401, ...) that you want to handle differently from the positive response. Currently, you have to configure an extra treatment for each individual status code, otherwise you will not have the status code.
It would therefore be good if the status code could be passed as an extra argument for (at least general) post-processing.
Implementation
In the "Additional arguments" section, "Response status code" can be selected and this can then be used in processing.