David Kimura PRO said over 4 years ago on Rails API Documentation :
Are you able to verify that the doc is generated and at that location? You should be able to do an `eb ssh` within the root of your application to SSH into the environment. From there, look under `/var/app/current/public/docs` to see if it is there. If it is, check the URL to see if you're able to access the file. You may also need to edit your `config/environments/production.rb` file and set this entry `config.public_file_server.enabled = true`