... make transaction data available via the API
It appears that there are two key things missing from the current version of the Xero API:
The Tables part of the API does not currently have a connection to the Nominal Ledger (Account) Transactions
The Reports part of the API connects to several of the standard reports, but doesn’t connect to the Account Transactions report.
Either of these would allow a full list of transactions to be accessed via the API.
Lauren Burns commented
Agree this is a massive missing piece that would be incredibly helpful