How is the index frontmatter implemented?

[ZYJLiu]

On fumadocs site, some index.mdx files have an index: true frontmatter, which seems to be added in source.ts.

It seems that the frontmatter generates these cards links for pages in the folder. Where can I find where this index frontmatter is parsed to add these cards?

[fuma-nama]

You can see the docs page for the actual implementation