A

Protocol

HIGH

UCP profile carries all four required top-level keys

Profile carries top-level `version`, `services`, `capabilities`, and `signing_keys`. A profile missing one of the four required keys is treated as non-conformant — agent runtimes fall back to default behaviour and may skip the merchant.

What this check looks for

The UCP overview requires every profile to expose four top-level keys: `version` (string), `services` (array or object), `capabilities` (array or object), and `signing_keys` (array). We tolerate both root and top-level `ucp`-wrapped layouts. Any missing key fails the check; the evidence enumerates what's missing.

Which AI surfaces it affects

  • Google AI Mode (UCP)100
  • Microsoft Copilot70
  • ChatGPT (ACP)30
  • Meta AI30
  • Perplexity20

Weighted against the live specs — ACP 2026-04-17, UCP 2026-04-08.

How to fix it

Add every required top-level key to the UCP profile

Shopify

Developer
  1. Update your custom UCP template / handler to emit all four required keys, even if `capabilities` and `signing_keys` are empty arrays today.

BigCommerce

Developer
  1. Edit the edge worker / proxy producing `/.well-known/ucp` to include all four top-level keys.

WooCommerce

Developer
  1. Update your UCP handler / file to emit the four required keys — empty arrays are valid.

Custom / headless

Developer
  1. Emit `version`, `services`, `capabilities`, and `signing_keys` at the top level of your JSON document.
<!-- /.well-known/ucp -->
{
  "version": "2026-04-08",
  "services": [],
  "capabilities": [],
  "signing_keys": []
}

The spec it's pinned to

  • UCP overview — required profile keys

    Every UCP profile MUST declare `version`, `services`, `capabilities`, and `signing_keys` at the root. Missing any of these signals a non-conformant profile to agent runtimes.

UCP overview

Does your store pass this check?

Run the full audit — 82 checks across five AI shopping surfaces. Most tools only check whether you get mentioned; we check whether an agent can buy from you.

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