So has Amazon Marketplace Web Services and it is by a huge margin the worst API I've seen my share of bad ones over the years.

And yet it is still better than the Amazon Vendor Central API... which they forgot to build at all

Oh my. Vendor central is such a pita one can't help thinking they do it on purpose. (Also, I had to write several puppeteer based scripts for different reporting web apps that don't expose an API and vendor central was definetly the most painful to write)

And ads API, is just so bad. And data is only available for the last 3 months.

One of my clients has been waiting for over 3 months for a reply for access to that API. Right now they are stuck manually processing hundreds of orders per day.

Dm me I have access and can help. I’m specializing it helping amazon sellers.