{
  "contacts": [
    {
      "externalId": "lead-123",
      "email": "john.doe@example.com",
      "firstName": "John",
      "lastName": "Doe",
      "phone": "+1234567890",
      "company": "Acme Inc",
      "title": "CEO",
      "linkedinUrl": "https://linkedin.com/in/johndoe"
    }
  ]
}

{
  "results": [
    {
      "externalId": "lead-123",
      "crmId": "crm-contact-456"
    }
  ]
}