Routing is not the same as truth
Discovery hints — files like llms.txt and agents.txt — tell automated systems which paths matter, how often to revisit them, and sometimes what to avoid. They are useful when your site is large or when you want a clear policy boundary between marketing pages and commerce pages.
They do not replace product facts. If price, availability, or GTINs are wrong or missing, a polite routing file will not persuade an assistant to recommend the SKU.
Keep a simple mental stack
Start from data the agent must trust: Schema.org JSON-LD on the product URL, Merchant Center / feed alignment where you sell, and stable identifiers (barcodes) on the variant.
Layer policy and discovery files on top once that base is honest. New transport and commerce protocols (for example tooling that connects catalog systems to assistants) matter for how integrations are wired — but merchants still win or lose on whether the underlying record is complete, consistent, and reviewable.
What to verify before chasing new acronyms
Validate structured data on real PDPs, not sample templates. Check that feeds reflect what shoppers see. Resolve GTINs deliberately when your category expects them.
When those boxes are in place, publish and maintain llms.txt and agents.txt as the readable contract between your site and crawlers — short, current, and aligned with where your product truth actually lives.