Tapwhich

Use this when someone asks which of their credit or debit cards to pay with at a shop, app, category or city, to get the most cashback. Pass the place (a merchant such as Grab or Shopee, a category such as dining or supermarket, or a city such as Tokyo, or both: 'dining in Tokyo') and the cards they hold (names or ids). It answers in one line, 'use card X here, because Y, up to cap Z', with the second-best card, each card's cap and conditions, and the bank source link. The data pack covers Vietnam-issued cards; amounts are in VND.

{
  "type": "object",
  "properties": {
    "place": {
      "type": "string",
      "minLength": 1,
      "maxLength": 120,
      "description": "Merchant, category or city, for example 'Grab', 'supermarket', 'dining in Tokyo'."
    },
    "cards": {
      "type": "array",
      "minItems": 1,
      "maxItems": 20,
      "items": {
        "type": "string",
        "maxLength": 80
      },
      "description": "The cards the person holds, by name ('VPBank Z JCB') or id ('vpbank-z-jcb')."
    },
    "amount": {
      "type": "number",
      "exclusiveMinimum": 0,
      "description": "Purchase amount, in VND unless currency says otherwise. Default 1,000,000 VND."
    },
    "currency": {
      "type": "string",
      "pattern": "^[A-Z]{3}$",
      "description": "ISO code of amount when the person gives a foreign amount, such as JPY for 8,000 yen. The tool converts at its own dated rate; do not convert yourself."
    },
    "date": {
      "type": "string",
      "pattern": "^\\d{4}-\\d{2}-\\d{2}$",
      "description": "Purchase date YYYY-MM-DD. Default today in Vietnam."
    },
    "channel": {
      "type": "string",
      "enum": [
        "online",
        "pos"
      ],
      "description": "Online or in a shop, when the place alone does not say."
    },
    "statement_spend": {
      "type": "object",
      "additionalProperties": {
        "type": "number"
      },
      "description": "Spend so far this statement by card id, for minimum spend and tiers."
    },
    "picks": {
      "type": "object",
      "additionalProperties": {
        "type": "array",
        "items": {
          "type": "string"
        }
      },
      "description": "Bonus categories picked on pick-N cards, by group (vib-one, vib-max, cake-freedom, msb-mdigi)."
    }
  },
  "required": [
    "place",
    "cards"
  ],
  "additionalProperties": false
}

{
  "type": "object",
  "properties": {
    "answer": {
      "type": "string"
    },
    "place": {
      "type": "object"
    },
    "amount": {
      "type": "number"
    },
    "currency": {
      "type": "string"
    },
    "converted_from": {
      "type": [
        "object",
        "null"
      ]
    },
    "date": {
      "type": "string"
    },
    "best": {
      "type": [
        "object",
        "null"
      ]
    },
    "second": {
      "type": [
        "object",
        "null"
      ]
    },
    "ranking": {
      "type": "array",
      "items": {
        "type": "object"
      }
    },
    "check": {
      "type": "string"
    },
    "freshness": {
      "type": [
        "string",
        "null"
      ]
    },
    "pack": {
      "type": "object"
    }
  },
  "required": [
    "answer",
    "place",
    "amount",
    "currency",
    "date",
    "ranking",
    "check",
    "pack"
  ]
}