Short answer
A website becomes machine-readable when its public assets are structured clearly enough that a system can tell what each route, file, and page is for without guessing.
In practice that usually means
- Clean URLs
- Distinct content types
- Public JSON files with explicit fields
- Markdown or low-noise text sources
- Stable titles, descriptions, and relationships
What this does not mean
It does not mean abandoning design or writing for machines only. It means the public architecture is clean enough that machines can follow along without reverse-engineering the site.
Why it matters
The more guesswork a system has to do, the less reliably it can cite, rank, or reuse your content.