Guide
ACP vs UCP: what is the difference in agentic commerce?
Short answer: ACP (Agentic Commerce Protocol) is how assistants like ChatGPT complete instant checkout with participating merchants, backed by OpenAI and Stripe. UCP (Universal Commerce Protocol) is how agents discover products and negotiate checkout with merchants on an open catalog standard, co-developed by Shopify and Google.
They solve different layers of the same problem, and the useful question is not which one wins. It is what neither of them answers: whether the supplier on the other end will actually deliver.
Side by side
Both are open standards for agentic commerce. The useful distinction is where each one shows up and what it standardizes.
Where each wins
ACP wins when the buyer is already in an assistant and a merchant has opted into that assistant’s instant-checkout program. Friction drops: the human (or agent surface) never leaves the chat to finish a participating purchase.
UCP wins when you need a shared language for catalog search, cart, discounts, and checkout across many merchants, not just the ones wired into one assistant. It is the broader "speak commerce" format for agents calling stores.
- Choose ACP-shaped flows when the product is assistant-native checkout.
- Choose UCP-shaped flows when the product is multi-merchant discovery and capability negotiation.
- Expect both to coexist. The same agent may see ACP in one channel and UCP on the open web.
What actually decides the order
Here is the part the protocol comparison hides. A wire format tells you how to ask. It does not tell you who to ask. Both standards will happily hand your agent a cheap offer from a supplier that will miss the date, refuse the rail, or never answer the quote.
The fields that decide a real purchase order are not in either spec, because they cannot be declared by the merchant. They have to be observed:
- Execution readiness. Can an agent complete this checkout right now, on a rail it actually holds? Scored as an Agentic Execution Score, calibrated on real order outcomes.
- Stated against observed delivery. What the merchant promised, next to what actually happened on the last orders, per carrier.
- Reputation on both sides. Merchant and product ratings that come from settled orders, not from who paid for placement.
- Rail payability. An offer your agent cannot pay is not an offer, however well-formed the handshake is.
What neither one solves
Protocols move data and complete handshakes. Left alone, agentic commerce still fragments into walled gardens: approved-merchant allowlists, curated catalogs, restricted rails, and pay-for-rank.
For an operator, that fragmentation has one concrete cost. When you are sourcing under pressure, a garden hands you a shorter list. The supplier that could have covered you is not ranked badly in it. It is invisible to it, because it never enrolled.
The layer above both
Conduit does not try to be the protocol. The wire format is being commoditized to zero by trillion-dollar consortia, and winning it is not available to anyone. Conduit is the decision-and-execution layer above all of them: one identity, every handshake, nothing to redo when the next standard lands.
That layer is worth something only if it knows your supply. Connector reads vendors, lead times, on-hand stock, and inbound out of the ERP you already run and puts that graph in Hub, whichever platform it was stored in. Pipes then watch those lines and keep ranked, payable alternates warm before you need one.
If you already self-host agents, you can skip the ladder and point them at the MCP endpoint today. Either way, there is no fee between the agent and the merchant, and rank is never for sale.
Frequently asked questions
- Which protocols power agentic commerce?
- The main open standards are UCP (Universal Commerce Protocol, by Shopify and Google), ACP (Agentic Commerce Protocol, by OpenAI and Stripe), and MCP (Model Context Protocol, by Anthropic) for data and tools, plus AP2 and x402 for agent payments and A2A/A2CN for agent-to-agent negotiation. Conduit speaks all of them so an agent needs only one identity.
- How is Conduit different from Amazon, Shopify, or a Google shopping garden?
- Those are walled gardens: approved-merchant allowlists, curated catalogs, restricted rails, pay-for-rank, and per-transaction fees, all controlled by one giant. Conduit is neutral ground: every merchant, every payable rail, every carrier, ranked purely on the merits, with no fee between agent and merchant and no allowlist.
- What is UCP (Universal Commerce Protocol)?
- UCP is an open standard, co-developed by Shopify and Google and launched in 2026, that lets AI agents discover products, negotiate capabilities, and complete checkout with any participating merchant. Conduit adopts UCP as one normalized input while keeping reputation and execution scoring neutral and cross-platform.
- What is ACP (Agentic Commerce Protocol)?
- ACP is an open standard from OpenAI and Stripe that powers instant checkout inside AI assistants like ChatGPT. Conduit rides ACP as one discovery and checkout path among many, so an agent is never locked to a single assistant or payment processor.