Get Virtual Pack spec

Use this endpoint to retrieve the latest JSON schema for the MP_VIRTUAL_PACK_BUNDLE feed type. The schema helps you validate your feed, build the payload correctly, and confirm required fields and constraints before upload.

This endpoint is available only to sellers who are enabled for Virtual Packs and onboarded to MLMQ. Contact Support for access.

Reference guide

This guide explains how to retrieve the latest JSON schema for the MP_VIRTUAL_PACK_BUNDLE feed type. For implementation details, refer to the Virtual Packs API reference guide.

POST https://marketplace.walmartapis.com/v3/items/spec

Request sample

curl -X POST "https://marketplace.walmartapis.com/v3/items/spec" \ -H "WM_QOS.CORRELATION_ID: b3261d2d-028a-4ef7-8602-633c23200af6" \ -H "WM_MARKET: US" \ -H "WM_SVC.NAME: Walmart Marketplace" \ -H "WM_SEC.ACCESS_TOKEN: eyJraWQiOiIzZjVhYTFmNS1hYWE5LTQzM....." \ -H "WM_GLOBAL_VERSION: 3.1" \ -H "Accept: application/json" \ -H "Content-Type: application/json" \ -d '{ "feedType": "MP_VIRTUAL_PACK_BUNDLE", "version": "5.0.20260508-19_30_00-api" }'

Request body

{ "feedType": "MP_VIRTUAL_PACK_BUNDLE", "version": "5.0.20260508-19_30_00-api"
}

Request fields

Modify your code

Use the sample request as a starting point, then update the values below to retrieve the schema version you need.

1. Replace WM_SEC.ACCESS_TOKEN with your valid access token.
2. Use a unique WM_QOS.CORRELATION_ID for each request.
3. Set feedType to MP_VIRTUAL_PACK_BUNDLE.
4. Set version to the schema version you want to retrieve.
5. Omit productTypes for virtual pack requests.

Response

On success, the API returns schema models for the requested feed type and version. Use the returned schema to validate the MP_VIRTUAL_PACK_BUNDLE feed before upload.

{ "schemaModels": [ { "dataModel": "Product", "schema": { "title": "MPItemFeed", "properties": { "MPItemFeedHeader": { "properties": { "feedType": { "enum": [ "MP_VIRTUAL_PACK_BUNDLE" ] } } }, "MPItem": [ { "Orderable": { "required": [ "price", "bundleComponentItemQuantity", "bundle_component_gtin" ] } } ] } } } ], "errors": null
}

Result

You now have the Virtual Pack schema for the requested version. Use the schema to validate your MP_VIRTUAL_PACK_BUNDLE feed before submitting it.

Errors and remediation

Next steps

After retrieving the schema:

1. Validate your Virtual Pack feed against MP_VIRTUAL_PACK_BUNDLE.
2. Build the feed payload using the required fields and constraints from the schema.
3. Submit the feed with Create or update Virtual Packs.
4. Use Get items with Virtual Packs to verify the published offer.