KiPart has been around for about a year. It takes a CSV spreadsheet file describing the pins of a part (or parts) and generates a KiCad schematic library.
I’ve added another utility to KiPart called kilib2csv. It “completes the circle” and allows KiCad libraries to be converted to CSV files that can serve as the input to KiPart. This allows you to take one or more existing KiCad libraries, convert them to a CSV file, edit all the parts in a spreadsheet, and then regenerate the library with KiPart.
I developed this primarily to use libraries of parts where they didn’t set the pin types correctly (i.e., they just made every pin an input). Making the wholesale changes was easier in a spreadsheet than laboriously clicking on every pin in the library part editor.
The only downside is that any graphics for the part symbol are discarded. (KiPart draws every part as a box.) That doesn’t matter to me since I’m moving away from designing schematics graphically and all I need is the pin data, but it might make a difference to you.
I also added the capability to set the part reference prefix for each part within the spreadsheet. (Previously, it just defaulted to “U”.)