Use of api key on the public instance (two questions)

hi,
I’m trying a system that automates the tests,
I would like some advice on how to take the results data:

/csv.php?test= …
or
/results.php?test=XXXX&f=xml

I noticed that using wptagent the format of the result data is different depending on the browser used;

there is a way to get data with a unique format?
(e.g. univocal field names etc.)

Thanks for your help
R.