---
title: Checkout MCP and Cart MCP now support UCP buyer consent - Shopify developer changelog
description: Shopify’s developer changelog documents all changes to Shopify’s platform. Find the latest news and learn about new platform opportunities.
source_url:
  html: https://shopify.dev/changelog/posts/checkout-mcp-and-cart-mcp-now-support-ucp-buyer-consent
  md: https://shopify.dev/changelog/posts/checkout-mcp-and-cart-mcp-now-support-ucp-buyer-consent.md
---

October 16, 2026

# Checkout MCP and Cart MCP now support UCP buyer consent

DateOctober 16, 2026

FlagsNew

SurfacesUCP

Checkout MCP and Cart MCP now support the UCP buyer consent extension (`dev.ucp.shopping.buyer_consent`) starting with UCP `2026-08-25`. Buyers can now make the same privacy and marketing choices in your agent that they'd make in a shop's own checkout, like opting in to email or SMS. Shops receive those choices with the cart, checkout, and order.

## What changed

Storefronts now list `dev.ucp.shopping.buyer_consent` in their discovery profiles at `/.well-known/ucp`. This extension applies to both cart and checkout.

If your agent profile negotiates `dev.ucp.shopping.buyer_consent` on UCP `2026-08-25`:

* Checkout MCP and Cart MCP responses include a `buyer.consent` object.
* `buyer.consent` lists each consent purpose that the shop supports, its current state, a description, and links to the shop’s policies.

Shopify storefronts advertise at least these consent purposes:

* `dev.ucp.consent.analytics`
* `dev.ucp.consent.preferences`
* `dev.ucp.consent.sale_or_sharing`
* `dev.ucp.consent.marketing`, with `email` and `sms` segments

You can send the buyer’s consent choices when you create, update, or complete a cart or checkout. If you don’t send consent, Shopify applies the shop’s default settings for the buyer’s country. If the buyer's country is unkown, consent defaults to opt-out.

Some choices require a contact detail, such as an SMS opt-in without a phone number. In that case, the response includes a `missing_consent_data` warning, and the checkout can’t complete until you provide the missing detail.

## Who's affected

Platforms and agents that use Checkout MCP or Cart MCP with UCP `2026-08-25` and negotiate the `dev.ucp.shopping.buyer_consent` extension are affected.

Integrations that don’t declare this extension, or that negotiate an earlier UCP version, aren’t affected.

## Why this matters

This change lets your agent present accurate, store-specific consent options during cart and checkout, record the buyer’s explicit choices, and respect the shop’s default rules when consent isn’t provided. This reduces custom logic for regional defaults and helps merchants meet their consent and communication requirements.

## What to do

1. Declare the `dev.ucp.shopping.buyer_consent` extension at version `2026-08-25` in your agent profile.
2. When you render cart or checkout, show each consent option to the buyer using the shop’s description and policy links from `buyer.consent`.
3. When the buyer makes a choice, send that choice back on cart and checkout create, update, or complete calls, and set `source: "platform"` only for choices that the buyer actually made during your flow.
4. If you receive a `missing_consent_data` warning, collect the required contact detail from the buyer and retry so the checkout can complete.

## Related docs

* [Understand Carts and Checkout MCP for agents](https://shopify.dev/docs/agents/carts-and-checkout)
* [Configure agent profiles and UCP negotiation](https://shopify.dev/docs/agents/profiles)
* [Review the UCP buyer consent specification](https://ucp.dev/2026-08-25/specification/shopping/extensions/buyer-consent/)