Hey @Paul_H,
I took a look at the Braintree API documentation, and it looks like that you will have to use their SDK to parse the JSON. If you’re self-hosting n8n, you can install the SDK on the server and use the NODE_FUNCTION_ALLOW_EXTERNAL variable to make it available in the Function node.
You can learn more here: [HELP] Not been able to import external modules - #12 by jan