How do we include markdown in between stories without MDX?

[matthew-dean]

In blog posts, it mentions that MDX compiles down to CSF. But it doesn't say how or how to define MDX features within a CSF.

The use case is that MDX is hard to debug. It doesn't have auto-complete or TypeScript support, and we sometimes get errors that are not easy to reason about. Whereas CSF is usually more straightforward with more logical errors.

However, there doesn't seem to be any clear API / spec for CSF anywhere. This repo points to https://storybook.js.org/docs/react/api/csf and there it says there's an "open standard" which points to this repo. But what is the spec exactly? What are all available exports and the supported object keys? How does one provide documentation in between stories? How does MDX compile / transpile to CSF?