Running jarg on crontab

[btoztas]

I'm trying to run jarg on crontab, simple by doing this:

jarg foo=bar

but I get this error:

Traceback (most recent call last):
File "/usr/bin/jarg", line 9, in
load_entry_point('jarg==0.4.1', 'console_scripts', 'jarg')()
File "/usr/lib/python2.7/site-packages/jarg/cli.py", line 66, in main
context = dialect.from_literal(sys.stdin.read())
File "/usr/lib/python2.7/site-packages/jarg/dialects.py", line 41, in from_literal
return json.loads(value)
File "/usr/lib64/python2.7/json/init.py", line 338, in loads
return _default_decoder.decode(s)
File "/usr/lib64/python2.7/json/decoder.py", line 366, in decode
obj, end = self.raw_decode(s, idx=_w(s, 0).end())
File "/usr/lib64/python2.7/json/decoder.py", line 384, in raw_decode
raise ValueError("No JSON object could be decoded")
ValueError: No JSON object could be decoded

I've placed all my env variables on crontab.

Any thoughts on how to solve it?

Thanks