2026-04 Release Notes

Inventory

We have redesigned the inventory endpoints to use POST request bodies instead of query parameters, added new response fields, and improved consistency across the API.

Breaking Changes

• POST /inventory (was GET): Now accepts a JSON request body (InventoryRequest) instead of query parameters. The response returns a flat array of Inventory objects instead of a { data: [...] } wrapper.
• POST /inventory_levels (was GET): Now accepts a JSON request body (InventoryLevelsRequest) instead of a JSON-encoded options query parameter. The response returns a flat array of InventoryLevel objects instead of a { data: [...] } wrapper.
• GET /inventory_levels/{product_id}: The inactive parameter (integer 0/1) has been renamed to include_inactive (boolean). The totals object has been removed from the response.
• Quantity field changes: inventory_level and quantity have been split into current_inventory_level and quantity_to_procure. In older APIs, stock required for fulfillments and services was represented as negative quantity values. In the 2026-04 API, this is now represented as positive quantity_to_procure values. This is not a straight renaming — consumers relying on negative values in quantity or inventory_level must update their logic.

Updated Endpoints

• POST /inventory: List inventory records. Supports filtering by product_id, variants, after, before, include_deleted, pagination via size (max 5000), and sort_direction.
• GET /inventory/{product_id}: List inventory records for a single product. Improved product_id and variants parameter descriptions to clarify variant matching behavior.
• POST /inventory_levels: List inventory levels. Now supports group_variants and to_be_procured_only filters. The out_of_stock_only and group_by parameters have been removed. product_ids and root_product_ids are now documented as mutually exclusive. size now has an explicit maximum of 10,000.
• GET /inventory_levels/{product_id}: List inventory levels for a single product.

Schema Changes

Inventory

• inventory_level has been renamed to current_inventory_level.
• New fields: quantity_to_procure, average_cost, deleted_at, version, reorder_target, reorder_method.

InventoryLevel

• quantity has been renamed to current_inventory_level.
• New fields: root_product_id, quantity_to_procure.
• Removed: levels object (containing producible and on_hand).

Deprecations

• GET /inventory: Deprecated. Please use POST /inventory instead.
• GET /inventory_levels: Deprecated. Please use POST /inventory_levels instead.

Gift Cards

New 2026-04 Gift Card and Gift Card Transaction endpoints are now available. These endpoints follow the 2026-04 API conventions while delegating to the same underlying gift card business logic.

New Endpoints

Gift Card Resource

Gift Card Transaction Resource

Key Changes

• Response structure: All responses return the resource inside a top-level data key in the response object.
• Monetary values as strings: Fields such as balance, total_sold, total_redeemed, and amount are now returned as strings for precision.
• POST returns 201: Create endpoints now return 201 Created instead of 200 OK.
• system_id support: The GET gift card by transaction ID endpoint accepts an optional system_id query parameter (defaults to x-series, also supports e-series).