This comes up fairly regularly and there have been several proposals in the past about standardizing fields - they seem to cause a lot of disagreement…
Following discussions here on the forum , on the KiCAD libraries GitHub and the developers mailing list it seems there is no consensus on setting up default names in KiCAD or the standard symbol libraries as an acceptable solution to encouraging interoperability between third party tools.
It is therefore up to the community of tool builders to decide on a standard to follow, to prepare a document that describes it and to put it up online somewhere and badger people when they don’t use it. …
A github issue requested that KiCost support a field called PartNumber (or something like that) that the KiCad libraries now had for each symbol. I’ve got a nightly Windows version of KiCad and I’ve examined and grepped the symbol libraries but can’t find any field like that. Does such a field exist? Is it in the standard libraries that are installed with the nightly builds, or is it somewhere else?