A developer ran arc install certificate instead of arc install-certificate and the error message was very confusing:
> arc install certificate Trying to connect to server... Exception Conduit URI '/api/' must include a valid host. (Run with `--trace` for a full exception trace.)
Here's what's happening, in detail:
We accept any unique prefix of a command as that command, so arc install-cer is the same as arc install-certificate, so long as there are is no arc install-ceramics or similar. If there are, we list alternatives:
$ arc l Usage Exception: Unknown command 'l'. Try 'arc help'. Did you mean: land liberate lint linters list
There are no other commands which begin with install, so arc install is equivalent to arc install-certificate. Expanded, this gives us:
$ arc install-certificate certificateThe argument is treated as a server URL, so it's correct for it to fail, but we're mangling it badly by the time it gets to an error message. The /api/ stuff gets added on later, largely for historical reasons.