how to strongly type kline-candlestick request results in F#

As is documented here, a request to the kline endpoint returns a list with all the data such as kline open time etc. In the docs it is commented out. Why is this endpoint not strongly typed, so that you can access the data easier inside your program? e. g.:

    "OpenTime": 12345674,
    "High": 13.0,
    "CloseTime": 12345675

My attempt at doing this, aka casting untyped list to a proper object is the following:

type KlineRecord = {
    OpenTime : decimal
    OpenPrice : decimal
    HighPrice : decimal
    LowPrice : decimal
    ClosePrice : decimal
    Volume : decimal
    CloseTime : decimal
    QuoteAssetVolume : decimal
    NumberOfTrades : decimal
    TakerBuyBaseAssetVolume : decimal
    TakerBuyQuoteAssetVolume : decimal
    Ignore : decimal

let kline symbol interval =
    market.KlineCandlestickData(symbol, interval)
    |> Async.AwaitTask
    |> Async.RunSynchronously
    |> Kline.Parse
    |> (fun f -> {
        OpenTime = f[0]
        OpenPrice = f[1]
        HighPrice = f[2]
        LowPrice = f[3]
        ClosePrice = f[4]
        Volume = f[5]
        CloseTime = f[6]
        QuoteAssetVolume = f[7]
        NumberOfTrades = f[8]
        TakerBuyBaseAssetVolume = f[9]
        TakerBuyQuoteAssetVolume = f[10]
        Ignore = f[11]

Hope you guys can give me some feedback on my approach, and whether we can ask someone to change the api for easier access.

Thanks for feedback, we may improve it later, for now we just return the original data from server.