Following my attempts to create and learn Context's ways to manage fonts, I would like to ask about the following:

I've created the structure for fonts in texmf-local folder and after running scripts they are listed. The output for Roboto Flex is as follows:

identifier                          familyname   fontname            filename         subfont   instances

robotoflex                          robotoflex   robotoflexregular   robotoflex.ttf             thin extralight light regular medium semibold bold extrabold black extrablack thinitalic extralightitalic lightitalic italic mediumitalic semibolditalic bolditalic extrabolditalic blackitalic extrablackitalic

What is the proper way to use family name or font name to create a typescript file and a goodies file to take advantage of optical sizes. Google's Roboto Flex is an upgraded Roboto as a variable font.

I know that this topic has been discussed many times and I've read the fonts manual but still have these questions. Most of the examples are rather ready solutions or templates but not always cover ways how to figure out values from scratch and how they correspond.

Thanks for help,

Pawel