Specify empty Content-Type for unauthorized requests in Swagger

In order to generate a complete swagger.json file, I specify all possible return statuses for my minimal .NET API methods, which look like this:

app.MapGet(rootPattern, async (MyDbContext db) =>
{
    return await db.Something.Where(x => x.SomeCondition).ToListAsync();
})
    .Produces(200)
    .Produces(401)
    .RequireAuthorization();

However, this will now specify a 401 result as having a content type of application/json, while in reality, .NET does not set Content-Type (and returns no content) when the request is unauthorized. (A side effect is that our testing suite (ApiDog) will always mark the request as Failed because the Content-Type does not match the expected value).

I can do this .Produces(401, typeof(string), "text/plain"), which is somewhat better and satisfies ApiDog, but still not quite correct.

So my question is: Can I specify a 401 response without Content-Type? Or alternatively, can I configure my app in a way so that a 401 has some kind of json response (e.g. { "status":"401" })

Or alternatively, can I configure my app in a way so that a 401 has some kind of json response (e.g. { "status":"401" })

You could add a middleware as below:

app.Use(async (context, next) =>
    {
        await next.Invoke();
        if (context.Response.StatusCode == 401)
        {
            await context.Response.WriteAsJsonAsync(new ResponseModel() { statuscode=401});
        }
    });
    
    app.UseAuthentication();
    app.UseAuthorization();
    
    ....
    app.Map(....)

Result: