curl "https://server.smartlead.ai/api/v1/client/?api_key=YOUR_KEY"

{
  "ok": true,
  "data": [
    {
      "id": 301,
      "name": "Acme Agency",
      "email": "admin@acme.com",
      "created_at": "2025-12-01T10:00:00.000Z"
    },
    {
      "id": 302,
      "name": "Beta Corp",
      "email": "admin@beta.com",
      "created_at": "2025-12-05T14:00:00.000Z"
    }
  ]
}

{
  "message": "Invalid API Key"
}