Research
Primary sources, verbatim quotes, dated
What the vendor documents actually say about AI shopping visibility — verified by the same weekly agent run that checks every Shelfgrade audit rule. When a spec changes, it shows up here with the before/after language. RSS
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The AEO Quickstart
The full framework in one page: how AI answers are assembled, which crawlers gate visibility, what markup and feeds each surface consumes, and the priority order to fix things in.
- Spec watchOct 7, 2026
Spec Watch #002: OpenAI's product feed now requires nine fields, not twelve
OpenAI rewrote its product feed reference between Aug 28 and Sep 9, 2026. The search and checkout flags and target_countries are no longer required on every row, availability_date left the native schema, and two length caps are gone. Shelfgrade's audit now follows the new rules.
- ExplainerSep 1, 2026
Shopify stores and ChatGPT Shopping: what's automatic, and what's still on you
OpenAI says Shopify product data flows into ChatGPT with “no additional work” from merchants — yet in our all-Shopify readiness panel, 20% of top stores block Perplexity and 20% ship no Product JSON-LD. The feed is automatic; the rest of AI visibility is not.
- DataSep 1, 2026
We scanned 40 top DTC stores for AI-shopping readiness. 1 in 5 is invisible to Perplexity.
Original scan data across 40 well-known DTC brands: 20% block PerplexityBot outright, 20% ship no Product JSON-LD at all, and half are missing GTIN in their product markup — the field Google-compatible feed parsing can require.
- ExplainerAug 29, 2026
Blocking GPTBot does not remove you from ChatGPT Shopping
The most common robots.txt mistake in AI-shopping advice: conflating OpenAI's training crawler with the bot that actually gates ChatGPT answers. The vendor docs are unambiguous.
- ExplainerAug 29, 2026
Is GTIN required in OpenAI's product feed? It depends which parser you hit
OpenAI's feed pipeline runs two parser profiles with different identifier rules. GTIN is optional in one and effectively required in the other — and the selection logic is documented.
- ExplainerAug 29, 2026
Google-Extended does not affect Google Shopping, Search, or AI Overviews
The robots.txt token everyone blocks 'to be safe' controls Gemini training and grounding — and Google states outright that it has no effect on Search inclusion or ranking.
- Spec watchAug 29, 2026
Spec Watch #001: the ten load-bearing rules, verified
The baseline entry for our weekly spec-verification run: the ten vendor-doc claims every Shelfgrade audit stands on, each re-checked against the primary source. Current status: claims 1 and 5 drifted when OpenAI rewrote its feed reference (Spec Watch #002); the other eight hold.