cli's help messages are too abstract, e.g. nothing toxic specific about toxiproxy HOT 1 OPEN

There's a couple reasons why things were done the way they are, though that's not to say they couldn't be improved.

The first is that having all clients toxic independent (and this this case, the cli is a client), means that when a toxic is added or changed, no further development time is needed to update all the clients, they will work as-is.
This is important for 3rd party clients especially, though for things like the cli and toxiproxy-ruby it's just a matter of ease of development.

The second reason is that toxiproxy does have support for 3rd party toxics, which currently only require using github.com/Shopify/toxiproxy and an include to build a custom server binary.
Requiring a cli build as well makes that process much more complicated, unless the generic format is also kept, but having a separate usage pattern for these toxics seems counter productive to me.

Some sort of way to list available toxics on the server seems like a reasonable addition, though I'm not sure of the best way to handle toxic fields in that scenario.
The experience for new toxiproxy users is definitely something that could be improved, it will take some discussion to figure out what changes to make though

from toxiproxy.