API reference / Changelog / 2026

API changelog: 2026

Every change to the Kintsugi API in 2026, newest first. For the latest changes and every release, see the API changelog.

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Area: Products

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2026-09-17

Breaking changes

Returns the existing product when a product is created twiceProducts

Breaking changeProducts

Creating a product with an external_id and source that already exist used to fail with 409 Conflict. It now succeeds with 200 and returns the stored product unchanged: the fields in the request are not applied. A product you deleted is restored instead, with status PENDING, and is not used in tax calculation until it is approved again. Creating a new product now answers 201 instead of 200.

Endpoints

POST/v1/productsv1

What to do

Treat both 201 and 200 as success.
Stop relying on 409 to detect an existing product.
To change an existing product, update it with PUT /v1/products/{product_id}.