UCP radar · public data from /.well-known/ucp
Mercatian.

Report · Q3 2026

State of Agentic Commerce

July 23, 2026

First quarterly report built from the Mercatian radar's data: which stores speak UCP today, how mature they are, and what is missing for the protocol to land in Spain.

Executive summary

  • 01100% of tracked active UCP stores (51) are AI-agent ready: all expose MCP transport and keep 2+ protocol versions alive.
  • 02The ecosystem is a Shopify monoculture: 100% of active profiles are platform-generated. WooCommerce and PrestaShop — 44% of Spanish e-commerce — still have no path to UCP.
  • 03No store publishes signing keys (JWK): the protocol's signed requests (RFC 9421) are not yet possible in practice.
  • 04Europe is marginal ahead of the official rollout (7 active stores across FR, GB and SE) — and with the UK confirmed for late 2026, Spain's preparation window is narrowing.

The radar in numbers

70
stores tracked
51
with active UCP profile
100%
AI-agent ready (MCP)
0
publish signing keys
6
countries
223
snapshots archived

1 · One ecosystem, one platform

All 51 active profiles share structure, versions and payment handlers: every one is generated automatically by Shopify. The consequence for Spain is direct — WooCommerce (26% market share) and PrestaShop (18%) publish no UCP profiles, so nearly half of Spanish e-commerce currently has no way to participate in agentic commerce. Whoever builds that bridge controls the on-ramp.

2 · Agent-ready by default

100% of active stores expose an MCP endpoint — the native transport for AI agents — and all declare Google Pay among their payment methods. Adoption is not experimental: agentic purchasing infrastructure ships by default wherever Shopify reaches.

3 · The signing-key gap

Not a single store publishes a JWK Set, the mechanism that verifies signed requests (RFC 9421). It is the criterion behind the UCP Score concentration: 45 stores score 92 and 6 score 88 — all losing exactly the same 8 key points. Until platforms solve this, the protocol's trust layer remains incomplete.

4 · Geography: Europe still on the periphery

The United States concentrates 31 of the 51 active stores; France and the United Kingdom have 3 each, Sweden 1. With the UK rollout confirmed for late 2026, the European — and Spanish — preparation clock is running. Spain still registers no active UCP store.

5 · What comes next: trends in Q4

The radar archives an immutable snapshot of every verification (223 since July 20). Starting next quarter, this report will answer the question nobody else can: not just how many stores speak UCP, but how fast the ecosystem grows and changes.

Methodology

Mercatian radar data as of July 23, 2026: 70 domains tracked from public registries, seed lists and direct submissions; /.well-known/ucp profiles fetched, validated and re-verified hourly; UCP Score computed over 14 public criteria (breakdown visible on every store page). Cite this report by linking to this page.

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