Currently you can only get the list of dweets for a thing-name but for a personal project I needed to be able to get the value of a key so I've now added this functionality.

Example
send a normal dweet with 2 keys

curl "https://dweet.cc/dweet/for/thing-name?key1=foo&key2=bar"

Retrieve the value of key1

curl https://dweet.cc/get/dweet/for/thing-name/key1
"foo"

Retrieve the value of key2

curl https://dweet.cc/get/dweet/for/thing-name/key2
"bar"