If I understand correctly, this is approximately how I should produce an output:

expositionFormats.findWriter(accept)
 .write(System.out, registry.scrape(), EscapingScheme.fromAcceptHeader(accept));

The problem with this is that the API forces me to pass the accept header twice, so theoretically I can do this:

expositionFormats.findWriter(acceptHeaderOne)
 .write(System.out, registry.scrape(), EscapingScheme.fromAcceptHeader(acceptHeaderTwo));

Which can lead to inconsistencies, it is easy to misuse the API.
I'm wondering if something like this would make sense:

expositionFormats.findWriter(accept).write(System.out, registry.scrape());

and the writer would have the EscapingScheme.
The writer still can be cached but it would be a little more than today.