Retrieve article object including its image using the Shopify JavaScript Buy SDK custom query

I'm using the shopify-buy SDK to try and fetch the articles off of my Shopify store just using JavaScript on the frontend, following the "Expanding the SDK" directions here: https://shopify.github.io/js-buy-sdk/#expanding-the-sdk.

Using the code below, I am able to retrieve my articles and some of the fields that I need.

// Build a custom query using the unoptimized version of the SDK
const articlesQuery = client.graphQLClient.query((root) => {
  root.addConnection('articles', {args: {first: 10}}, (article) => {
    article.add('title')
    article.add('handle')
    article.add('url')
    article.add('contentHtml')
  })
})

// Call the send method with the custom query
client.graphQLClient.send(articlesQuery).then(({model, data}) => {
  console.log('articles data')
  console.log(data)
})

However, I really need to pull the featured image for each article as well, and unfortunately, when I add the line article.add('image') in my articlesQuery, the resulting articles data logs null. I tried building a custom productsQuery, and that has a similiar problem - I can retrieve some of the product fields, but when I try add the line product.add('images'), I just get null back from the storefront API.

Does anyone have experience building custom/expanded queries and successfully retrieving images?

from Retrieve article object including its image using the Shopify JavaScript Buy SDK custom query