Undocumented option:

TAG option: -T

$ TAG=ENV:KEY:VALUE ./burneye -T TAG -o ls /bin/ls
$ ./ls
README  README.private  burneye  fingerprint  ls
$ ENV=KEY ./ls
VALUE
$ ENV=KEY_ ./ls
ÒB9^"g06š!ùñûï›`1¼å¤ÚØÔÂûL
$