I stumbled upon this site when taking a trip down memory lane. Recalling the FILE_ID.DIZ file format[0] from my BBS days, I typed in the closest matching URL (file-id.biz) and found this curious interface.
I've only found one command so far after a bit of exploring: help → "I am not what I am."
Hah, nice find —- this is mine, it was briefly a weird little puzzle based on Shakespeare (“I am not what I am” -> Iago), though I haven’t used the http endpoint for much in awhile and it doesn’t work anymore. Now that I work at the Internet Archive, I should make it an interface to some of our BBS archives!