> It won't scan cards with AI - you manually enter the barcode, which I think makes it less prone to error.

This is a very interesting sentence.

I interpret this sentence as saying that manually entering a barcode is less error prone than letting AI do it, that AI would have an unacceptable margin of error (and this is probably an accurate assessment).

But you don't need AI to find or read barcodes. Finding and reading barcodes is a reasonably mature technology that has existed long before AI.

Barcodes exist as a fast, machine readable data transfer format meant to avoid data entry errors by avoiding manual data entry, and yet you've implemented manual entry in order to avoid errors?

Now, if one of the constraints you've put on your implementation is that it work only in the browser and you don't want to have to download a large barcode scanning library to the browser, then it makes sense to implement manual entry. But that has nothing to do with AI.

That being said, there are some barcode reading apps that can be used to prompt for a scan from a web page, and you get the barcode payload back. I've used an app called "bineye" on Android (source on GitHub) that works like this. This helps avoid error prone manual entry and gets the full barcode payload (many barcodes store/encode more information than the human readable text printed next to them).