Distinguished Engineer, @Shopify. On a mission to make commerce better for everyone.
Portland, OR
Joined November 2007
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@tobi and I sat down to talk UCP and the art of protocol design. A couple of themes worth expanding on...
The hard part of good protocol design isn't the spec. It's the deep understanding of the problem you're solving and the humility to approach it at the right level. Commerce is infinitely complex and always evolving; it's hubris to pretend anyone can 'spec commerce'.
But wait — isn't UCP trying to do exactly that?
No, UCP doesn't 'spec commerce'. It models the rules of the bazaar that make commerce possible. The job of UCP is to build the boring parts: the small core of common and composable primitives, and the discovery and negotiation mechanisms that everything else runs on. Done right, this lets commerce thrive in the open, with merchants, agents, and buyers deciding what is advertised, supported, and adopted, not by fiat from a protocol committee. This is UCP. 👇🏻🧵
Ilya Grigorik retweeted
We made a good version of both of these within a day … and then we were like “but what if…” over and over again.
Working with @igrigorik and @suprb on this was so fun that I laughed basically every day out of disbelief from how ridiculous we were making it.
We pushed these marketing sites to the limit, and then kept pushing.
Built a full terminal in the browser (you can mkdir/echo/cd/whatever) on shop.dev, and on shop.md made what is now my favourite markdown editor.
Publish a skill to see my favourite Easter egg.
Yo dawg, heard you like MCP. So we compiled the shop CLI (an MCP client) to WASM, put it in a browser terminal, and exposed it over #WebMCP, so your agent can call MCP tools that call MCP tools.
Silly? Yes. Necessary? No. Fun? Abso-yes-lutely. 😆
But really, try the playground on shop.dev!
1B+ products from millions of Shopify stores, cart → checkout → Shop Pay, order tracking. Bonus, try `shop spend-request`: buyer approves in Shop, your agent gets a single-use payment credential, and checks out anywhere on the web.
$> npm install --global @shopify/shop@latest
$> shop skill --install
From discovery to purchase, batteries included.
Yo dawg, heard you like MCP. So we compiled the shop CLI (an MCP client) to WASM, put it in a browser terminal, and exposed it over #WebMCP, so your agent can call MCP tools that call MCP tools.
Silly? Yes. Necessary? No. Fun? Abso-yes-lutely. 😆
But really, try the playground on shop.dev!
1B+ products from millions of Shopify stores, cart → checkout → Shop Pay, order tracking. Bonus, try `shop spend-request`: buyer approves in Shop, your agent gets a single-use payment credential, and checks out anywhere on the web.
$> npm install --global @shopify/shop@latest
$> shop skill --install
From discovery to purchase, batteries included.
Ilya Grigorik retweeted
All the tools we used to create this skill are open to devs at shop.dev/
Ilya Grigorik retweeted
Turn any existing Agent into the world's best personal shopper for you.
The new shop skill: shop.md/
Add the skill & connect your Shop account & finally find the thing that you always wanted
Behind the curtain: we upgraded UCP to offer rich media (video, 3D models, and whatever else you want to bring). Live on Shopify Catalog! 🎉
PR: github.com/Universal-Commerc…
Ilya Grigorik retweeted
This was truly a labour of love. Hope you enjoy the magic of Shop Pay everywhere, dear internet. LFG 🚀
Ilya Grigorik retweeted
Shopify merchants are live in @Meta Muse! 🎉 I've had early access and it's just so good. Well built and awesome for shopping. Leveraging Shopify's Catalog, UCP, and Shop Pay.
Meta just launched a brand new app. Muse.
Here's what matters if you're a founder: Shopify merchants are already discoverable. If your products are in Shopify Catalog and shipping to the US? You're in.
Muse didn't exist yesterday. Today our merchants can already sell through it.
That's the advantage of building on @Shopify in the agentic era.
Agentic commerce comes batteries included on @Shopify, with frontier capabilities. Your move, agents.
Ilya Grigorik retweeted
UCP, the universal commerce protocol is growing better and better shopify.com/ucp/2026-08
🎉 UCP 2026-08 release is out. MASSIVE upgrade.
👉🏻 shopify.com/ucp/2026-08/
Agents can prove their identity and negotiate identity providers for the buyer; read the terms that govern a purchase down to the individual line item; split a payment across instruments (e.g. gift cards) without splitting the checkout; negotiate payment terms and schedules (due now vs. later); find nearby physical stores that carry what they need; transact in any unit (each, weight, length, whatever); navigate a 3DS challenge with new action primitives; use and build cart permalinks that can travel anywhere a URL can go (QR codes, email, chat), ..., and SO. MUCH. MORE.
88 improvements. 40 contributors. 21 weeks.
Agents: time to cook!
ALT Interactive tour of 2026-08 UCP release
Need a fast start for UCP? Install the UCP CLI+skill:
$> npm install -g @shopify/ucp-cli
$> ucp skills add
Boot up your agent and ask it to search for products, or build a cart/checkout. Yes, that simple.
See: github.com/Shopify/ucp-cli
Ilya Grigorik retweeted
I built a shopping agent inside iMessage. Open sourcing the code: github.com/gil--/ucp-agent-i…
1. Send a msg or photo.
2. It searches Shopify’s global catalog.
3. Builds one cart per merchant.
4. Connects Shop identity w/ budget.
5. No cc details exposed.
Why Shopify? Shop identity already covers hundreds of millions of buyers.
One protocol (UCP), every merchant. Millions of products. No scraping or “computer use”is necessary. 💚
Instinct shows how far LLM computer use has come but it’s still awfully slow 😴 and no one wants to share payment (or address) credentials with a 3p. 😱
Here’s a short demo of my agent, Concierge using Shopify’s UCP tools and our Shop identity tokens to directly checkout with spend controls.
👋 If you’re building in this space, let’s work together to enable seamless agentic commerce.
Shipped AgentBoard 0.9, huge upgrade.
👉 github.com/igrigorik/AgentBo…
You can now mount a local workspace that will auto load your AGENTS.md, IDENTITY.md, etc. Better yet, it unlocks read+write support for MEMORY.md — the agent can save and retrieve context across threads, and everything lives as plain markdown on your device.
h/t @tobi for the workspace nudge, huge unlock.
p.s. bonus: did you know that millions of Shopify storefronts ship 🪄 WebMCP tools for catalog + cart? Makes a *huge* difference in speed and quality of agents assisting the user on the storefront.
Ilya Grigorik retweeted
Thanks for the UCP origin story talk - one of the best sessions at DotDev. I'd built frunkandtrunk.com on the Global Catalog a couple weeks before (an EV-accessory finder, all live lookups), so hearing the why behind the design was really helpful!
Fun chat. I stand by my claim: Shopify's Global Catalog is *the* gold rush opportunity of 2026. It's open, it's free, and it's agent ready to power discovery-to-checkout.
Docs @ shopify.dev/docs/agents/cata…
Demos: xitter.cf/vlaurenlee/status/2067…
UCP deep-dive: xitter.cf/igrigorik/status/20564…
"This is the biggest @ShopifyDevs opportunity right now."
@igrigorik, Distinguished Engineer at Shopify, shared more about the Universal Commerce Protocol (UCP) and what's coming next during DotDev.
The major moments:
- UCP is a free, public, global catalogue API.
Only Google, Amazon, and a few others have solved discovery at internet scale, and almost none expose it publicly.
Shopify spent $100M+ over two years and made it free. "This is a picks-and-shovels moment. There's gold in that mountain."
- Built with Google, launched in January.
Decades of Shopify scale compressed, plus partners like Target. By April, Meta, Salesforce, Amazon, and Stripe had joined.
- How UCP works.
A merchant declares what it supports like cards, checkout, subscriptions, split payments, gift cards. A client or agent says "I don't speak gift cards yet, but I understand subscriptions."
They negotiate the overlap and transact.
- Completely open participation.
A merchant can invent "fancy subscriptions" tomorrow, and any agent that speaks it can transact. It turns commerce into a market negotiation.
- Modelling all of commerce is absurdly hard.
It's the world's longest-running trade and always evolving, so you can't write a static spec. UCP is built around capability negotiation instead.
UCP aggregates across all merchants and normalizes the permutations (one seller's size 10 is another's 9.5; blue is someone's turquoise) into coherent availability, prices, and latency.
Thanks for coming on the show Ilya! We'd love to have you back.
Ecomm Cowboy is live every M-F at 12P CT.
Standard events and actions are gold, and key to unlocking entire new class of browser+agentic experiences with WebMCP. Don't sleep on it. – at Toronto, Ontario
Ilya Grigorik retweeted
This one's going to be a banger‼️Tag teaming on UCP's origin story with the one and only @igrigorik... Can't wait to see you all at @Shopify DotDev next week.
