FunnelEnvy's developer tools includes a browser console log that can be activated by appending the fe-log=true parameter to a running campaign.
As an example if you had a campaign running at https://www.example.com/campaignPage you could view this log by requesting the URL https://www.example.com/campaignPage?fe-log=true and opening your browser console.
The following information is logged:
Page targeting results for all running campaigns
Results of any browser condition functions
Audience evaluation & classification
Activated campaigns & variations
Javascript which is evaluated