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## GraphQL Schema Updates

New checkout error types, locale fields, cart option identifiers, and B2B terminology updates across the Storefront and B2B GraphQL schemas.

### Storefront GraphQL

* **Structured checkout errors expanded** — new `CheckoutBillingAddressError` and `CheckoutCouponError` types with `COUPON_EXPIRED`, `COUPON_INELIGIBLE`, `COUPON_INVALID`, `COUPON_INVALID_LOCATION`, `COUPON_MIN_PURCHASE`, `COUPON_MODIFICATION_NOT_ALLOWED`, and `COUPON_NOT_APPLICABLE` codes on `CheckoutErrorCode`
* **Checkout result errors** — new `CompleteCheckoutError` and `UpdateCheckoutError` unions surfaced through `errors` on `CompleteCheckoutResult` and `UpdateCheckoutResult`; `CreateCheckoutError` now includes `CheckoutCouponError`
* **Locale alternates** — new `locales` field on `BlogIndexPage`, `BlogPost`, `Brand`, and `Category` for localized alternate paths and URLs
* **Cart option identifiers** — new `attributeId` field on every `CartSelectedOption` variant and `addedByAttributeId` on `CartPhysicalItem` and `CartDigitalItem` to correlate items back to the option that produced them

### B2B GraphQL

* **B2B Edition rebrand** — schema descriptions referencing `BundleB2B` updated to `B2BEdition` across `userCompany`, `BCInfomation`, `OrderType`, `OrderedProductType`, `CompanyUserInfoType`, `CustomerInfoType`, `StoreSitesType`, and `UserAuthResultType`

For schema details, browse the [Storefront GraphQL API reference](/developer/api-reference/graphql/storefront/queries/site) and the [B2B GraphQL API reference](/developer/api-reference/graphql/b2b/b2b-graphql/queries/company-roles).