Maximise integrity,​ minimise hallucination​ - brightonSEO Oct 26

My talk from brightonSEO which was presented on 8th October 2026.

Agents are already reading your site and taking action on what they think you mean. The problem is that when your content leaves room for interpretation, a language model doesn't stop and ask. As a result fills this gap with whatever it deems most plausible - then responds with total confidence. These hallucinations are then attached to your brand, compounding throughout the session. Wrong answers are reiterated, then baked into the next round of model training where you have little to no control.

The solution lies at the data layer. Accuracy is favoured over scale, and maximising it is a job that already belongs to SEOs. This session covers why ambiguity is the new visibility problem, and how to remove the ambiguity before an agent does it for you.

Transcript

1. Maximise integrity, minimise hallucination Alex Moss Yoast / FireCask alex-moss.co.uk
2. It's up to SEOs to maximise data integrity & accuracy whilst minimising ambiguity & hallucinations
3. { "John worked at the shop for 40 years. He was basically a son to the owner, Robert. Robert's actual biological son, Mark, was estranged and lived abroad." "@context": "https://schema.org", "@graph": [ { "@type": "Person", "@id": "#robert", "name": "Robert Smith", "description": "The deceased business owner" }, { "@type": "Person", "@id": "#mark", "name": "Mark Smith", "parent": { "@id": "#robert" }, "description": "Biological son who lived abroad for 20 years" }, { "@type": "Person", "@id": "#john", "name": "John Doe", "description": "Caretaker who lived with Robert, often called 'my true son' in letters" }, { "@type": "Organization", "@id": "#familyBusiness", "name": "Smith & Sons Bakery", "owner": { "@id": "#robert" }, "employee": { "@id": "#john" } } ] }
4. "Sangue e Grafi" by WordLift Frontier LLMs fall for the story. A small model reads the graph. Sangue e Grafi, Andrea Volpini & Chiara Carrozza, WordLift
5. EntityMap x Bing
6. There is no general consensus or agreed standard
7. <h2 class="section-title" id="about">About Us</h2> ## About Us
8. "Converting pages to markdown is such a stupid idea." John Mueller, Google "Really want to double crawl load?" Fabrice Canel, Bing
9. "Converting pages to markdown is such a stupid idea." John Mueller, Google "Really want to double crawl load?"
10. <link rel="alternate" type="text/markdown" href="/article.md"> or content negotiation
11. OKF
12. ARD
13. Knowledge catalog
14. 99.37% drop in payload weight when serving the same URL as Markdown. 500 KB HTML → 3 KB Markdown vercel.com/blog/making-agent-friendly-pages-with-content-negotiation
15. The biggest event of the summer was legal, not technical.
16. AMAZON ARGUED THE NINTH CIRCUIT FOUND Perplexity is accessing our systems without authorisation. Amazon's customers are. The agent acts for them. Computer Fraud and Abuse Act. Injunction granted November 2025, keeping the Comet shopping agent off Amazon. Unanimous, 4 August 2026. Injunction vacated. Blocking the agent is blocking the customer. Narrow: limited to this record, no broader principle on agentic AI. Reporting: PYMNTS; Wilson Sonsini client alert.
17. Schema.org covers most of the moat
18. Schema.org's ItemTypes
19. Schema.org ItemType visibility: June - Sept Google crawl of schema.org term usage, published monthly at schemaorg/schemaorg/data/public_stats/google. Parsed from the May, June, July and August 2026 files.
20. 16 ItemTypes on 10m+ domains Twelve in May. Four arrived since, and three of the four are commerce. Organization Person WebPage WebSite BreadcrumbList ListItem ImageObject EntryPoint Thing PropertyValueSpecification ReadAction SearchAction Product Offer PostalAddress Article crossed in June crossed in June crossed in June crossed in July Google crawl of schema.org term usage, August 2026 file. Two Actions were already in this list; that has not changed.
21. BuyAction moved up two buckets Bucket positions per month, May to August 2026 files. Bands are domain-count buckets, not linear counts.
22. Trust needs to be earned Kyle Risley, Shopify, 11 August 2026. Q2 2026 Shopify storefront data.
23. UCP in the past 100(ish) days 2 Jun 16 Jun 14 Jul 4 Aug 25 Aug 2 Sep Hey Savi + PayPal: UK's first agentic checkout. Debenhams first retailer Adyen Agentic ships with UCP, AP2 and ACP support, plus Meta AI checkout x402 Foundation launches under the Linux Foundation with 40 members Ninth Circuit vacates the Amazon v Perplexity injunction on Comet UCP v2026-08-25: breaking release, 3DS2, grocery, deposits and instalments UCP Payments Tech Council seated: Adyen, Ant, Coinbase, Global Payments, Google, PayPal, Shopify, Stripe 10 Jun 17 Jun 23 Jul 19 Aug 28 Aug 8-9 Sep Visa × OpenAI. Mastercard AP4M. Stripe: UK Agentic Commerce Suite "later this year" Shopify Spring '26: 150+ updates built on UCP. Schema.org adds @list ordering UCP merges the Actions primitive (#582). Food Technical Council formed a week earlier Adobe: July AI referrals to US retail up 62%, converting 60% better Lodging TC files dev.ucp.lodging.book ing, the first capability outside shopping W3C/GS1 workshop on e-commerce for humans and agents, Zurich, hosted by Google
24. Three ways an agent can buy from you Yoav Weiss and Ilya Grigorik, Shopify, W3C/GS1 Zurich, 8 September 2026. WebMCP is in Chrome and Edge origin trial, has OpenAI Codex support, and is deployed on Shopify storefronts.
26. GS1 Databar
27. GS1 Digital Link
28. GS1 Digital Link Resolver
29. Schema & Merchant Center
30. Universal Cart make this seamless
31. Agentic grounding stack
32. Stuff to look into next week 1. Stabilise @ids; add sameAs to Wikidata etc 2. Test natural language interpretation with NLWeb 3. If you're Ecom – complete full Product feed audit, look into ACP & UCP 4. Look into Schema Actions. Ensure BuyAction is implemented on top-converting products 5. Implement WebMCP 6. Enable content negotiation/markdown serving
33. Don't chase the protocol. Own the layers underneath.
34. It's up to SEOs to maximise data integrity & accuracy whilst minimising ambiguity & hallucinations
35. Thank you! @alexmoss @alexmoss1