Function: get_credit_card_balance
Description: This tool belongs to the travel system, which allows users to book flights, manage credit cards, and view budget information. Tool description: Get the balance of a credit card
Parameters:
type: dict
properties: access_token: type: string
description: The access token obtained from the authenticate
card_id: type: string
description: The ID of the credit card
required: access_token, card_id
Response:
type: dict
properties: card_balance: type: float
description: The balance of the credit card