There are a set of CRM fields you can use to get details about the Contacts from the API.
"crm_company_id": "string",
"crm_company_link": "string",
"crm_company_name": "string",
"crm_contact_full_name": "John Smith",
"crm_contact_id": "AJS939FN39FNFN",
"crm_contact_link": "string",
"crm_contact_type": "Contact",