Commerce & Payments · Integration
Walmart Seller
Add Walmart Seller to your product for your customers, and give your AI agents governed access to it.
A Walmart Seller integration puts marketplace operations inside your product: orders to acknowledge and ship, items and their published status, returns, and the price and inventory updates that keep listings live. The fact that shapes every build here is that bulk changes are asynchronous. You submit a feed, get a feed id back, and learn nothing about success until you poll that id and read the per-item results, where a feed can be accepted overall while individual items fail validation. Orders behave differently again, needing acknowledgement before shipment, and buyer detail is deliberately limited to what fulfilment requires. fastn holds each seller's credentials, polls feeds to completion and keeps up with Walmart's API versions.
In your product
Embedded for your customers. Per-tenant auth, no per-customer code, maintained by fastn.
Let a seller connect their own Walmart account so your product acknowledges and ships their orders without a spreadsheet.
Submit price and inventory feeds from your product and surface the per-item results once the feed id reports back.
Read item status so a seller can see which listings are published, unpublished or held for a data problem.
Handle returns alongside orders, so a refund raised on the marketplace reaches the records your product keeps.
For your AI agents
Governed, audited access for the agents you build, through the MCP server.
An agent reports which orders are still unacknowledged and past their expected ship date for one seller.
An agent submits an approved price change as a feed and reports the outcome once the feed finishes.
An agent explains why an item failed validation by reading the feed result rather than guessing.
Example prompt
Which Walmart items failed on my last inventory feed, and what did the feed report for each?
Set up Walmart Seller in 4 steps
- 01Enable the Walmart Marketplace connector from your fastn dashboard.
- 02Have each customer authorise their own Walmart Marketplace account, so calls run under their credentials rather than a shared key.
- 03Decide which orders, items, returns and feeds your product needs, and plan for feeds being asynchronous, so you submit and then poll a feed id.
- 04Call it from your product and expose it to your agents through the same governed connection.
Why teams use the Walmart Seller integration
What you get by embedding it with fastn instead of building it yourself.
- Ship a Walmart Seller integration without building it. Your customers connect their own Walmart Seller account inside your product and work their orders, payments and customers there, with no per-customer code on your side.
- Handle the part that actually costs time: money and order state must never be double-applied, and reconciliation has to be possible. fastn owns the auth, token refresh, rate limits, pagination and breaking-change fixes, so a Walmart Seller update is not your on-call problem.
- One integration serves your product and your agents. The same governed Walmart Seller connection powers in-product features and gives AI agents scoped, audited access, so you keep commerce and payment records in step with your product without wiring it twice.
Used by these teams
Compare with
Amazon Seller Central
eBay
ChannelEngineOften used alongside
Tools the same teams tend to run next to Walmart Seller, across other categories.
NetSuite
Notion
Box
DocusignWalmart Seller integration FAQ
How do I add a Walmart Seller integration to my product?
Enable the Walmart Seller connector in your fastn dashboard, then let each customer authenticate their own Walmart Seller account. fastn handles the OAuth flow, token storage and refresh per tenant, so there is no Walmart Seller client code in your app and no per-customer branch in your codebase. Setup is 4 steps.
Do my customers each connect their own Walmart Seller account?
Yes. Every connection is scoped to the individual customer, so each authorises their own Walmart Seller account and only ever sees their own orders, payments and customers. That per-tenant isolation is the point of an embedded integration: you support the long tail of customer setups without maintaining an integration per customer.
Can AI agents use this Walmart Seller integration?
Yes. The same connection is exposed to your agents through the fastn MCP gateway, with permissions scoped per tenant and every call audited. An agent reports which orders are still unacknowledged and past their expected ship date for one seller.
Who maintains the Walmart Seller integration?
fastn does. When Walmart Seller changes an endpoint, deprecates a field or alters its auth, the fix lands in the connector rather than in your backlog, and your customers' connections keep working.
Is the Walmart Seller integration safe for payment and order writes?
Writes are idempotent, so a retry cannot double-charge or duplicate an order, and every call is logged per tenant so a transaction can be reconciled against the event that triggered it.
Can my product react to a new order, payment or refund immediately?
Yes, through event triggers, so fulfilment, entitlement or accounting steps run as soon as the event lands rather than on a nightly sync.
What can I build with the Walmart Seller integration?
A common starting point: let a seller connect their own Walmart account so your product acknowledges and ships their orders without a spreadsheet. Teams also use it for the other use cases listed above, and expose it to agents for governed reads and writes.
How much does the Walmart Seller integration cost?
It is included. Pricing is based on connected accounts, not on how many connectors you enable, so adding Walmart Seller does not change your per-connector cost. You can start free with 3 connected accounts.
Add Walmart Seller to your product
Start free with 3 connected accounts. No sales call required, and no per-customer integration code.