On https://letsencrypt.readthedocs.org/en/latest/using.html#plugins there is a chart listing the plugins. There are columns titled “A” and “I” (I have highlighted them in the photo below).
I am assuming these columns stand for “Authorization” (meaning the plugin can perform authorization of the requested domain to get a cert from Let’s Encrypt) and “Installation” (meaning the plugin can install/configure the certificate on the user’s server).
Is this accurate? If so, may I suggest some sort of elaboration on that page to make it more clear.