Issue #3 — Sources

Published April 17, 2026

This is the sources post for Issue #3. If you haven’t read the issue yet, start there.

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OpenAI killed Instant Checkout and pivoted to product discovery

OpenAI’s own announcement, March 24, 2026: https://openai.com/index/powering-product-discovery-in-chatgpt/

The direct quote used in the issue (“did not offer the level of flexibility”) is from this post.

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Target, Sephora, Nordstrom, Lowe’s, Best Buy, Home Depot, Wayfair already integrated into ACP for discovery

Same OpenAI announcement above.

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Shopify merchants now in ChatGPT through Shopify Catalog

Shopify’s announcement of UCP and Agentic Storefronts: https://www.shopify.com/news/ai-commerce-at-scale

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Agentic Storefronts activated by default for all Shopify stores, late March 2026

Ask Phill guide, citing Shopify Winter ‘26 Edition: https://askphill.com/blogs/blog/agentic-commerce-for-shopify-protocols-platforms-and-what-to-prioritize-in-2026

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Shopify Catalog Mapping — product description warning

First-party observation. Screenshot taken April 16, 2026 in a Shopify admin. Settings → Sales channels → Agentic Storefronts banner → Preview products → Catalog Mapping.

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UCP co-developed by Shopify and Google, endorsed by 20+ retailers and platforms

Shopify engineering post on UCP architecture: https://shopify.engineering/ucp

UCP official site, listing co-developers (Google, Shopify, Etsy, Wayfair, Target, Walmart) and endorsers: https://ucp.dev/

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ACP co-developed by OpenAI and Stripe

OpenAI announcement of Instant Checkout (original ACP launch): https://openai.com/index/buy-it-in-chatgpt/

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Correction policy

If anything in Issue #3 is wrong, I’ll fix it publicly here and note the date and what changed. Email sacha@paidaisearch.com if you spot an error.