<verbatim>
% fossil help artifact
Usage: fossil artifact ARTIFACT-ID  ?OUTPUT-FILENAME?
</verbatim>

There is no way to specify a repository to extract the artifact directly without having to open it first.

On the same line:

<verbatim>
% fossil help test-parse-manifest
Usage: fossil test-parse-manifest FILENAME ?N?
</verbatim>

There is absolutely no reason why it needs a repository at all. Not helpful when debugging why a rebuild failed.