Custom fields

Your own fields, added to any record type the product offers one for — a customer, a project, whatever your firm tracks that the product does not have a column for out of the box.

When you would use this: your business tracks something specific that has no home anywhere else — an account number from another system, a renewal date, a category only you use.

Adding one: pick the record type from the selector at the top, then add a field with a label and a type (text, number, date, and the others the manager offers). The field's underlying key is fixed the moment it is created — renaming the label afterwards changes nothing about that key, so an export or an API integration built against it keeps working even after you rename what people see.

Retiring one: fields can be marked inactive rather than deleted outright, which is why the list can be switched to show inactive ones too — a field taken out of use does not erase the values already recorded against it.

A narrower view: seeing the fields on a record type needs only the read capability; adding, editing or retiring one needs a further capability, so a colleague who fills these fields in day to day may not be able to define new ones.

When it refuses: "Custom fields are not available to your role" means you cannot see them at all — ask an Owner or Admin. Seeing the list but not the controls to add or edit one means the same people can grant you the further capability.