I’ve recently done our claim via the new online system and had it paid 🙂.
I just summarised what was on the invoice as best as I could within the space and this seemed to work fine.
They asked to see 24 out of our 117 invoices. These were mainly the high value ones, not the ones where I had to summarise multiple items in the description.
So just do what seems sensible and if they want more info they’ll ask for it.
The turnaround was really fast!