You'll notice
Artifact file listing now clearly reports 'single page, no files' instead of a generic not-found error
What
When you list the files for an artifact that turns out to be a single page with no separately published files, the tool now returns a specific single_page error reason with a clearer explanation. Previously this case was lumped in with genuine not-found (404) errors and handled the same way.
Why
This makes it clear when an artifact simply has no separate files to list, rather than making it look like a broken or missing artifact.