curl -X POST "{{base_url}}/v1/exchange-rate" \
  -H "x-api-key: YOUR_CONSUMER_KEY" \
  -H "Content-Type: application/json" \
  -d '{"currency_code":"KES"}'

{
  "code": 200,
  "message": "Exchange rates",
  "data": {
    "buying_rate": 129.5,
    "selling_rate": 131.2
  }
}