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preview is currently in pre mode so this branch has prereleases rather than normal releases. If you want to exit prereleases, run changeset pre exit on preview.

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Releases

@shopify/hydrogen@2026.10.0-preview.3

Minor Changes

• 8827904: Add an account option to getShopifyScriptTags() and the React/Vue ShopifyScripts components. When enabled, Hydrogen loads the Shopify customer account web component (https://cdn.shopify.com/storefront/web-components/account.js) with the same nonce and crossorigin handling as the other Shopify runtime scripts. Render <shopify-account> where you want the account UI to appear. The script URL is also exported as SHOPIFY_ACCOUNT_SCRIPT.

• 96f9d2d: Add register("attributeValue", { key, value }) to ProductFormRegister for attaching line-item attributes (engraving text, gift messages, custom options) through the form-based add-to-cart path. Both client-side (getAddPayload) and server-side (parseAddIntent) now extract attributes.* entries from FormData. Exports two new types: ProductAttributeValueProps and ProductAttributeDefaultValueProps.

• d92f398: Add hydrogen skills check, which exits non-zero when the project's synced skills do not match the installed @shopify/hydrogen, or were never synced. It prints the summary skills sync would act on and writes nothing. The default --mode=error gates CI; --mode=warn prints the same message and exits zero for dev scripts.

• 05e43e6: Add hydrogen skills sync to keep packaged agent skills aligned with the installed @shopify/hydrogen version. Skills are always written to both .claude/skills and .agents/skills, covering Claude Code, Codex, Cursor, and OpenCode without configuration. Each copied SKILL.md records the package version and a content hash under frontmatter metadata. Rerunning the command after an upgrade overwrites unmodified skills, adds new ones, removes skills the package no longer ships, and leaves locally modified skills alone unless --force is passed. If you edited a skill the package no longer ships, you are asked before it is removed; without a terminal (for example in CI) it is kept and a warning is printed. hydrogen setup runs the same sync after installing the package and accepts the same --force, so rerunning it over previously synced skills now updates them instead of failing. Preview templates ship their skills with the same metadata, so skills sync works on deployed templates too.

  Projects that ran hydrogen setup before this version have skills without the metadata block. Run npx @shopify/hydrogen skills sync --force once to adopt them; later syncs then manage them normally. Skills from those earlier copies whose names are no longer shipped are not recognised and should be deleted by hand.

• 54a1e7e: Proxy caller-authenticated UCP MCP requests from /api/ucp/mcp to the configured Shopify store.

Patch Changes

• d8f8476: Add the hydrogen-cart-metafields skill: a behavioral guide for reading and writing cart metafields (custom cart data such as delivery instructions) through a custom CartFragment, an app-owned mutation route, and useCartActions().refresh().
• a6e3a71: Cart permalinks now hand off to the mock.shop demo store for every mock.shop host, not only mock.shop itself, so a storefront built against a per-store host such as pets.mock.shop behaves the same in mock mode. The hydrogen-storefront-client and hydrogen-setup skills now explain that mock.shop is a catalog of stores and how to pick one from https://mock.shop/llms.txt.
• c35ee9d: Prevent superseded cart mutations from producing unhandled AbortError console errors.