Artos vs generic UCP

Artos implements the Universal Commerce Protocol faithfully, then adds capabilities a generic UCP store does not have. If you have integrated a UCP store before (or read a generic UCP agent flow), this page is the diff.

Area	Generic UCP store	Artos
Buyer identity	Per-store; the agent re-collects address/payment each store	One Universal Buyer Account across every store via My Artos ; `get_buyer_context` returns address + caps
Store addressing	Often a shop domain root	Path-based: `https://api.artos.sh/s/{slug}`; discover the slug from `metadata.artos_seller.slug`
Global catalog	Vendor-specific or none	Cross-store search in one call (`search_products`), each result seller-annotated
Cart model	May offer a (cross-)cart	No universal cart — discover globally, then checkout per store, sequentially
Autonomous pay	Card / hosted handoff	AP2 mandates + Sui crypto rail — cryptographically bound, human-not-present checkout
Settlement	PSP payout	USDsui stablecoin on Sui in ~300ms; any token in, dollars out
Purchase call	`complete checkout` you assemble	`confirm_purchase` — re-price + verify terms + mint mandate + pick rail + complete in one call
Account tools	Rare	Buyer-account MCP (`list_my_orders`, `get_wallet_balances`, `list_my_coupons`, …), bearer-scoped

Things that trip up a generic UCP client

Transport headers are required. Every shopping call needs a Request-Id and a UCP-Agent: profile="…" header; MCP also repeats the profile in meta["ucp-agent"].profile. The buyer-account surface (/account/mcp) needs neither. See Direct UCP.
Two-credential auth. The API prefers X-API-Key over a bearer, so buyer-bound calls (crypto completion, all account tools) must send the buyer bearer only — never both. See Authentication.
Money units differ by surface. Catalog price filters are major units (dollars) on the bridge and SDK, but minor units (cents) on the raw wire. Totals are always integer minor units.
Rails are selected by inner id. Pick artos.card / artos.crypto, not the sh.artos.* registry key.
Crypto needs an Agents spend mandate, separate from OAuth consent — see Connect an assistant.

What Artos does not do (yet)

No universal/cross-merchant cart. Per-store checkout is intentional until the UCP spec and merchant demand justify a universal cart.
No merchant onboarding via this surface. These docs are for agent/buyer integrators; merchants use the dashboard (see For merchants for merchant-side UCP credentials).

Next steps

Connect an assistant — the full flow end to end
Profiles & trust — UCP profiles, negotiation, AP2 conformance
Direct UCP — the raw transport under the SDK