This is where webhooks and results are posted by CrowdFlower and where CPS retrieves them. You can manually download them or browse the webhook logfile.
Each time CrowdFlower posts a webhook, its signal attribute is stored here along with its date and hour.
A JSON formatted file containing the payload attribute of the last 'job_complete' webhook.
Once they are received, the results are parsed in order to be csv formatted (rather than json formatted). Why ?
This is where CPS posts the results.xml files it creates when the sort is over.