[B2BTEAM-3748] Accept optional priceToken on ItemInput (Pricing Fallback V2)

CHANGELOG.md

@@ -7,6 +7,10 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ## [Unreleased]
 
+### Added
+
+- Optional `priceToken` on `ItemInput` (Pricing Fallback V2), forwarded as-is to the checkout REST API on `addToCart` and `updateItems`, so storefronts can send the signed price returned by the search and the cart can be closed while the Pricing system is unavailable.
+
 ## [0.68.0] - 2026-06-12
 
 ### Fixed

graphql/types/Item.graphql

@@ -158,6 +158,13 @@ input ItemInput {
   uniqueId: String
   inputValues: InputValues
   options: [AssemblyOptionInput]
+  """
+  Signed price (Pricing Fallback) returned by the search for this SKU and
+  seller, forwarded as-is to the checkout REST API so it can close the cart
+  with that price while the Pricing system is unavailable. Optional: when it
+  is absent the payload reaches checkout exactly as before.
+  """
+  priceToken: String
 }
 
 input AssemblyOptionInput {

node/typings/global.d.ts

@@ -466,6 +466,7 @@ declare global {
     seller?: string
     uniqueId?: string
     options?: AssemblyOptionInput[]
+    priceToken?: string
   }
 
   interface AssemblyOptionInput {