Sources

Public pages were reviewed for this research on 19 October 2026. Supplier pages substantiate descriptions of their own published offerings, not independent effectiveness. Academic papers are research evidence, not universal procurement standards. URLs are listed below for editorial verification.

Platform documentation and industry guidance

1. Google — Generative AI performance report: https://support.google.com/webmasters/answer/16984139
2. Google — Optimising for generative AI features: https://developers.google.com/search/docs/fundamentals/ai-optimization-guide
3. Google — AI features and your website: https://developers.google.com/search/docs/appearance/ai-features
4. Google — Spam policies: https://developers.google.com/search/docs/essentials/spam-policies
5. Microsoft — Introducing AI Performance in Bing Webmaster Tools: https://blogs.bing.com/webmaster/2026/2/Introducing-AI-Performance-in-Bing-Webmaster-Tools-Public-Preview/
6. OpenAI — Searching the web with ChatGPT: https://help.openai.com/en/articles/9237897-searching-the-web-with-chatgpt
7. OpenAI — Overview of crawlers: https://developers.openai.com/api/docs/bots
8. OpenAI — Publishers and developers FAQ: https://help.openai.com/en/articles/12627856-publishers-and-developers-faq
9. OpenAI — API web-search documentation: https://developers.openai.com/api/docs/guides/tools-web-search
10. IAB — Measuring Visibility in the AI Era, publication page: https://www.iab.com/guidelines/measuring-visibility-in-the-ai-era/
11. IAB — Full August 2026 framework, particularly printed pages 21–30: https://www.iab.com/wp-content/uploads/2026/07/IAB_Measuring_Visibility_in_the_AI_Era_August_2026-1.pdf

Supplier documentation

12. Profound — Pricing and trial limitations: https://www.tryprofound.com/pricing
13. Scrunch — Pricing FAQ: https://scrunch.com/faqs/what-is-the-pricing-for-scrunch-plans
14. Scrunch — Pricing page returning conflicting package information: https://scrunch.com/pricing/
15. Scrunch — How AXP serves content: https://helpcenter.scrunchai.com/en/articles/12845899-how-axp-serves-content-to-ai-agents
16. Peec AI — Pricing and package capacities: https://peec.ai/pricing
17. Peec AI — Collection-method documentation: https://docs.peec.ai/intro-to-peec-ai
18. OtterlyAI — Pricing: https://otterly.ai/pricing
19. Semrush — AI Visibility pricing: https://www.semrush.com/pricing/ai/
20. Semrush — AI Visibility Toolkit documentation: https://www.semrush.com/kb/1493-ai-visibility-toolkit
21. Ahrefs — Brand Radar product and pricing: https://ahrefs.com/brand-radar
22. Ahrefs — Custom prompts, allowances and check-based billing: https://help.ahrefs.com/en/articles/13192745-how-to-set-up-custom-prompts-to-track-brand-visibility-in-ai-assistants
23. Ahrefs — Brand Radar methodology: https://ahrefs.com/blog/brand-radar-methodology/
24. Omniscient Digital — AEO services and published starting price: https://beomniscient.com/services/answer-engine-optimization/

Measurement research and US regulatory guidance

25. Schulte, Bleeker and Kaufmann — Don’t Measure Once: Measuring Visibility in AI Search (GEO), 8 April 2026: https://arxiv.org/abs/2604.07585
26. Sielinski — Quantifying Uncertainty in AI Visibility: A Statistical Framework for Generative Search Measurement, 9 March 2026: https://arxiv.org/abs/2603.08924
27. FTC — Consumer Reviews and Testimonials Rule questions and answers: https://www.ftc.gov/business-guidance/resources/consumer-reviews-testimonials-rule-questions-answers
28. FTC — Endorsement Guides questions and answers: https://www.ftc.gov/business-guidance/resources/ftcs-endorsement-guides-what-people-are-asking