This may be obvious, but I just spent some time on it so I’ll post it in case it can save anybody else a few minutes.

I was getting the Unknown Action errors from spiders requesting a robots.txt file, as noted earlier. Since it caused an Unknown Action error, which is thrown by Routes, I was thinking I needed to add an entry to my routes.rb file in config, but I was wrong. Just upload the file to your /public directory and you’ll be all set.