About martdata
martdata is a local bridge to HasData’s Walmart data service, providing product, review, and storefront search results as JSON. It offers read-only access through an MCP server and CLI, without cart or checkout operations.
Key features
- 01Retrieve product details by item ID or URL
- 02Browse and filter customer reviews
- 03Search products by keyword or category
- 04Filter by price, fulfillment, and sort order
- 05Use tools through CLI or MCP
Use cases
- 01Compare product prices and availability
- 02Inspect reviews for a specific product
- 03Find items within a price range
- 04Browse a Walmart category
MCP support
Exposes three read-only Walmart data tools to MCP clients and forwards calls to the hosted HasData MCP server. It also provides CLI subcommands for each tool.
Configuration
Local server config is the same for every client. Copy it into your client’s MCP config file.
Tools
3Saved tool list · updated 2d ago
| Parameter | Type | Required | Description |
|---|---|---|---|
| url | string | No | A full Walmart product URL to scrape as is. When provided, it overrides `itemId` and the storefront is taken from the URL itself. Required unless `itemId` is provided. |
| domain | enum | No | Walmart storefront the item belongs to. Each storefront has its own catalog, item ids, prices and currency, so an id from one storefront does not resolve on another. Ignored when `url` is provided. Default is `walmart.com`.walmart.com | walmart.ca |
| itemId | string | No | Walmart item id, taken from a product URL or from the id field of the Walmart Search API response. On `walmart.com` it is numeric (for example `14977205582`), on `walmart.ca` an alphanumeric code (for example `6NZMJ5CW6MH2`). Required unless `url` is provided. |
| language | enum | No | Language of the product details. Availability depends on the storefront - `walmart.com` serves `en` and `es`, `walmart.ca` serves `en` and `fr`. A language the storefront does not support falls back to its default.en | es | fr |
| otherOffers | boolean | No | Also collect the offers of other sellers competing for this item - each seller name, storefront, price, condition, shipping cost, delivery date and return policy. This takes an extra request to Walmart and costs 5 credits on top of the base 10, whether or not the item turns out to have competing sellers. How many competitors the item advertises, and the cheapest competing price, are returned in the `otherOffers` block whether the switch is on or off, so it can be left off until the count shows there is something to collect. Default is `false`. |
Details
From the project READMEmartdata
martdata is a small local bridge to the hosted HasData Walmart MCP server, which returns Walmart storefront data as JSON. It can pull one product page in full from an item id or URL, page through that product's customer reviews, and run keyword or category searches across a storefront with price, fulfillment and sort filters.
The bridge holds no product data of its own. It answers the tool list locally, exactly as captured from the live endpoint, and forwards each tool call upstream, returning whatever comes back untouched. The captured surface is three read-only fetches over public storefront data: there is no cart, checkout, order or payment tool in it, and no individual contact data is returned.
Tools
hasdata_walmart_product_getWalmartProduct— fetch one Walmart product in full, byitemIdor byurl(the URL wins when both are given). Optional:domain(walmart.com/walmart.ca),language(en/es/fr), andotherOffersto also collect competing sellers' offers. Returns title, brand, price and availability, the buy-box seller, ratings, variants, fulfillment details and the other-sellers block. No argument is marked required in the captured schema:itemIdandurlare alternatives for each other.hasdata_walmart_reviews_getWalmartReviews— the customer reviews of one product, ten a page, byitemIdorurl. Optional:domain,language,page,sort(most relevant, most recent, most helpful, highest or lowest rated, oldest),rating(one star value),aspectId(one frequent-mention topic),condition, andverifiedPurchasesOnly. Returns each review with its rating, text, author and vote counts, plus the item's rating breakdown, AI review summary, per-aspect scores and the filters block naming the values later calls can filter by.hasdata_walmart_search_getSearchResults— search a storefront by keywordq, or browse a category withcatId, or scrape a full search URL viaurl. Optional:domain,language,sort(best match, price low-to-high or high-to-low, bestseller, highly rated, new arrivals),page,minPriceandmaxPrice,deliveryType(shipping/pickup), andfacetnarrowing inname:valueform. Returns the product list with prices, ratings, sellers and fulfillment details, plus the facets block and pagination.
Configuration
HASDATA_WALMART_MCP_URL(optional) — override the upstream endpoint. Defaults tohttps://mcp.hasdata.com/mcp?apis=walmart. (The override hook is this rebuild's own labelled reconstruction.)HASDATA_API_KEY(optional) — when set, every upstream request carries anx-api-key: <key>header, for the caller's own HasData API key. When it is not set, no key header is sent. (The header name and the env name are pinned by the original's registry record; forwarding the key from this env var is a labelled reconstruction — the original surface was captured keyless.)
Forwarding mechanics
On the first tool call the client opens a streamable
HTTP session upstream: a JSON-RPC initialize request
(protocolVersion 2025-03-26, clientInfo name
martdata), then a notifications/initialized
notification, then the tools/call request carrying
the caller's arguments unchanged. When the upstream
answers initialize with an Mcp-Session-Id header,
that value rides on every later request of the
session, which is reused for the life of the process.
Replies may arrive as plain JSON or as server-sent
events; both are read.
Successful upstream results pass through verbatim,
including any isError flag the upstream sets.
Failures — a JSON-RPC error, a non-2xx status, an
unreadable response, or a request that cannot be
completed — come back as an isError result whose
text starts with martdata error: (this rendering is
this rebuild's own labelled reconstruction).
CLI
Each tool is also a subcommand taking one JSON argument string:
npx @reneturcios/martdata hasdata_walmart_product_getWalmartProduct '{"itemId":"14977205582"}'
npx @reneturcios/martdata hasdata_walmart_reviews_getWalmartReviews '{"itemId":"14977205582","sort":"mostRecent"}'
npx @reneturcios/martdata hasdata_walmart_search_getSearchResults '{"q":"coffee maker","maxPrice":90}'
npx @reneturcios/martdata --version
Exit codes: 0 on success, 1 on an isError
result, 2 on a usage error.
MCP server
npx -y @reneturcios/martdata mcp
MCP client config:
{
"mcpServers": {
"martdata": {
"command": "npx",
"args": ["-y", "@reneturcios/martdata", "mcp"]
}
}
}
Docker
docker run -i ghcr.io/cloudcorprecords/martdata
docker run --rm ghcr.io/cloudcorprecords/martdata --version
The container's default command is mcp, so the first
form is a stdio MCP server; any other arguments reach
the CLI normally.
Development
npm install
npm run build
npm test
npm run dev
The test suite runs entirely against a stubbed JSON-RPC upstream — no live network calls.
License
MIT — see LICENSE.
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