Where's the order item custom options labels in the REST API?

Question

I'm trying to retrieve orders from the REST API in Magento Enterprise 2.3.1, and that's easy enough with endpoints like /rest/default/V1/orders, but while I can see the values for custom options of the items in the order, I can't see their labels. For example:

"product_option": {
    "extension_attributes": {
        "custom_options": [
            {
                "option_id": "3730",
                "option_value": "Some text value."
            },
            {
                "option_id": "3731",
                "option_value": ""
            }
        ]
    }
}

It's great that I can see that for one of the custom options, the customer said "Some text value.", but I'd really like to know what it was they were responding to. What I'd expect to see for each custom option is something like:

{
    "option_id": "3728",
    "option_label": "What's your favorite Star Trek ship?"
    "option_value": "U.S.S. Excelsior"
} 

So far, any time I can find a way to load an order via the REST API, it is returned this way, and I don't see any other way to get the custom option label.

It's hard to believe I'm the first person to come across this - am I just missing something obvious?

Answer 1

You can retrieve the option labels from the catalog product endpoint like this:

GET /rest/default/V1/products/{sku}/options/{optionId}

The label will be returned in the response under title.