There's also two other important limitations to using an LLM and just providing it with pairs of records.

It does not know enough about the records in the context of the overall dataset:

- what is the data quality and to what extent do we expect a errors in some fields - how unusual are certain values such as names in the context of the dataset as a whole, e.g. some names would be very common in some countries but rare in others.

I've written in more detail about this here: https://www.robinlinacre.com/fellegi_sunter_accuracy/