curl --request GET \
  --url https://staging.api.commercengine.io/api/v1/{store_id}/storefront/pos/carts/{id}/evaluate-coupons \
  --header 'Authorization: Bearer <token>'

{
  "message": "<string>",
  "success": true,
  "content": {
    "applicable_coupons": [
      {
        "id": "<string>",
        "name": "<string>",
        "coupon_code": [
          "<string>"
        ],
        "estimated_discount": 123,
        "savings_message": "<string>"
      }
    ],
    "inapplicable_coupons": [
      {
        "id": "<string>",
        "name": "<string>",
        "coupon_code": [
          "<string>"
        ],
        "reason": "<string>",
        "suggestion": "<string>"
      }
    ]
  }
}