Some Lead Managers implement an API endpoint to parse JSONLead’s. Simple send the JSONLead as the payload of a POST HTTP Request. Here is a curl example:
curl -d '{"client": {"first_name": "John"},"sales_lead": \
{"car": {"make" : "Ford"}},"version": "1.0.0"}' \
-H "Content-Type: application/json" \
-X POST http://www.exampleCRM.com/saveLead