This help article lists the fields that SnapEngage sets when you use the default Salesforce integration settings:

If you select: “I use Salesforce for Support. Create contacts and cases.”
Cases
Subject –> “Live Chat with <name>” Or “Support Request from <name>”
Description –> <initial chat message>, <geo location>, <coming from url>, <os/browser info>, <language>, <js/other variables>
Origin –> “Web”
SuppliedEmail –> <visitor email address>
Type –> “SnapEngage”
ContactId –> <from Salesforce>
OwnerId –> <chat agent id – if agent mapping configured> (Or else defaults to Admin account)
Contacts
Email –> <visitor email address>
FirstName –> <from SnapEngage contact data> (If available)
LastName –> <from SnapEngage contact data> (or “t.b.d” if not available, since this is Required)
Description –> “SnapEngage user name: <contact data name>” (If available)
Title –> <from SnapEngage contact data> (If available)
Phone –> <from SnapEngage contact data> (If available)
If you select: “I use Salesforce for Sales. Create new leads.”
Leads
Email –> <visitor email address>
FirstName –> <from SnapEngage contact data> (If available)
LastName –> <from SnapEngage contact data> (or “t.b.d” if not available, since this is Required)
Description –> <initial chat message>, <geo location>, <coming from url>, <os/browser info>, <language>, <js/other variables>
LeadSource –> ”Live Chat” Or “Web Form” (If Offline request)
Title –> <from SnapEngage contact data> (If available)
Company –> <from SnapEngage contact data> (or “t.b.d” if not available, since this is Required)
Phone –> <from SnapEngage contact data> (If available)
OwnerId –> <chat agent id – if agent mapping configured> (Or else defaults to Admin account)
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