Brand Price & Stock Monitor (Shopify + Product JSON-LD)

Enter product page URLs and get one flat JSON row per variant: listed price, currency, in-stock status, SKU, barcode, and the price change since your last run.

Built for brands, distributors and sellers who watch known product pages on reseller and competitor stores every day or every week. It reads public Shopify storefront data and public Product JSON-LD with plain HTTPS requests. No browser, no proxy, no login.

What you get

• Variant-level rows. A product with 5 sizes gives 5 rows, each with its own price and stock status.
• Change tracking. Give the run a history name and every row gets isNew, isChanged, previousPrice and priceChange. Turn on onlyChanges to store only what moved.
• Your own product code on every row. Add productCode to link the same product across stores, for example your brand store and three resellers.
• Honest status per URL. Every URL ends as completed, partial, failed, blocked or budgetLimited in the free RUN_SUMMARY record. A page that could not be read is never reported as "out of stock" or as an empty result.
• Pay per URL checked. Failed and blocked URLs are free.

Which pages work

Page type	Works?	Notes
Shopify storefront product page (/products/<handle>)	Yes	Exact variant prices from the storefront's own data.
Any public page with Product JSON-LD (<script type="application/ld+json">)	Yes	Many WooCommerce, Magento, BigCommerce and custom stores.
Sites that block data-center traffic (HTTP 403 / 429, captcha)	No	This Actor uses no proxy. Such URLs end as blocked and are not charged.
Pages that render the price only with JavaScript and publish no JSON-LD	No	They end as failed with the reason.
Amazon, marketplaces, pages behind a login	No	Not supported.

In our test run of 40 product URLs on 9 stores, 38 were read (95%); see Reliability. Try your URLs once: a failed URL costs nothing.

Quick start

1. Paste product URLs into Product page URLs.
2. Run. Each variant is one dataset row.
3. For monitoring, set a History name (for example my-brand-prices) and schedule the Actor daily. From the second run on, rows show what changed.

Input

Only products is required.

Field	Type	Default	Description
products	array	required	Up to 100 product pages per run. Each item is a URL string or an object (see below).
historyStoreName	string	none	Name of a key-value store in your account that remembers the last saved observation. Turns on change tracking.
onlyChanges	boolean	false	Store only new or changed rows. Needs historyStoreName.
maxItems	integer	1000	Maximum rows stored per run.
maxRequests	integer	300	Maximum HTTP requests per run. A URL needs 1 request (JSON-LD) or 2 (Shopify).
maxRunSeconds	integer	600	Time budget. URLs not reached are budgetLimited and free.
requestIntervalMs	integer	1000	Pause between two requests (minimum 500).

A product object:

Key	Description
url	Public https product page. Required.
productCode	Your own label, copied to every row of this URL. Use the same code for the same product on different stores.
variantId	Store only this variant (Shopify variant id, or the JSON-LD offer SKU). A ?variant= in the URL does the same.
adapter	auto (default): JSON-LD first, and on a Shopify storefront fall back to the storefront's variant data. jsonld: JSON-LD only. shopify: Shopify data only.

Example 1: one product on the brand store and on a reseller

{
  "products": [
    { "url": "https://www.cosrx.com/products/advanced-snail-96-mucin-power-essence", "productCode": "cosrx-snail-essence" },
    { "url": "https://sokoglam.com/products/cosrx-advanced-snail-96-mucin-power-essence", "productCode": "cosrx-snail-essence" }
  ]
}

Example 2: daily monitoring, store only what changed

{
  "products": [
    "https://sokoglam.com/products/klairs-freshly-juiced-vitamin-c",
    "https://colourpop.com/products/lunch-money",
    "https://www.deathwishcoffee.com/products/medium-roast"
  ],
  "historyStoreName": "my-brand-prices",
  "onlyChanges": true
}

Example 3: one variant only

{
  "products": [
    { "url": "https://www.cosrx.com/products/advanced-snail-96-mucin-power-essence", "variantId": "51086327742680", "productCode": "snail-100ml" }
  ]
}

Output

One row per variant. All fields are always present; a value the store does not publish is null. Numbers are numbers.

Real rows from a run on 2026-10-02 (Example 1):

{
  "source": "shopify",
  "productCode": "cosrx-snail-essence",
  "productId": "9070057062616",
  "title": "Advanced Snail 96 Mucin Power Essence",
  "variant": "3.38 fl.oz / 100mL",
  "sku": "113020114",
  "gtin": "8809416470009",
  "price": 25,
  "currency": "USD",
  "available": true,
  "priceType": "listed",
  "lowerPrice": null,
  "upperPrice": null,
  "url": "https://www.cosrx.com/products/advanced-snail-96-mucin-power-essence",
  "currencySource": "source",
  "matchMethod": "customerSuppliedUrl",
  "offerIdentityType": "variantId",
  "recordKey": "https://www.cosrx.com/products/advanced-snail-96-mucin-power-essence|51086327742680",
  "schemaVersion": 1,
  "observedAt": "2026-10-02T07:09:03.715Z",
  "isNew": true,
  "isChanged": null,
  "previousObservedAt": null,
  "previousPrice": null,
  "priceChange": null
}

{
  "source": "product-jsonld",
  "productCode": "cosrx-snail-essence",
  "productId": "CRX110009",
  "title": "Advanced Snail 96 Mucin Power Essence",
  "variant": "10286705669",
  "sku": "CRX110009",
  "gtin": "8809416470009",
  "price": 20.9,
  "currency": "USD",
  "available": true,
  "priceType": "listed",
  "lowerPrice": null,
  "upperPrice": null,
  "url": "https://sokoglam.com/products/cosrx-advanced-snail-96-mucin-power-essence",
  "currencySource": "source",
  "matchMethod": "customerSuppliedUrl",
  "offerIdentityType": "offerId",
  "recordKey": "https://sokoglam.com/products/cosrx-advanced-snail-96-mucin-power-essence|/products/cosrx-advanced-snail-96-mucin-power-essence?variant=10286705669#offer",
  "schemaVersion": 1,
  "observedAt": "2026-10-02T07:09:03.715Z",
  "isNew": true,
  "isChanged": null,
  "previousObservedAt": null,
  "previousPrice": null,
  "priceChange": null
}

Field	Type	Description
source	string	shopify or product-jsonld: where the row was read from.
productCode	string | null	Your label for this URL.
productId	string | null	The store's product identifier.
title	string | null	Product title as published.
variant	string | null	Variant name, or the variant id when the store publishes no name. null for a single-offer product.
sku	string | null	Store SKU.
gtin	string | null	Barcode (GTIN / EAN / UPC) when published.
price	number | null	Listed price of the variant. null for a price range or when no price is published.
currency	string | null	ISO 4217 code published by the store. Never assumed.
available	boolean | null	true in stock, false out of stock or discontinued, null when the page does not say.
priceType	string	listed (exact variant price) or range (the page only publishes lowest and highest price).
lowerPrice, upperPrice	number | null	Bounds of a range offer.
url	string	The URL exactly as you gave it.
recordKey	string	Stable key of the variant (input URL + variant identity). Join runs on it.
offerIdentityType	string	Which key identifies the variant: variantId, offerId, offerSku, variantName or product.
currencySource, matchMethod	string	Constants: currency comes from the store; products are linked by your URLs, not matched automatically.
schemaVersion	integer	1.
observedAt	string	Run observation time, ISO 8601 UTC.
isNew	boolean	Not in the history before (always true without a history name).
isChanged	boolean | null	Differs from the last saved observation. null when new.
previousObservedAt	string | null	Time of the last saved observation.
previousPrice	number | null	Last saved price, only when both observations have the same known currency.
priceChange	number | null	price - previousPrice. Negative means cheaper.

Dataset views: Prices and stock (core columns) and Identifiers (SKU, GTIN, product id).

Run summary (free)

The key-value record RUN_SUMMARY has one entry per URL. Shortened real example from the 40-URL test run:

{
  "status": "partial",
  "stopReason": "someTargetsIncomplete",
  "targetsRequested": 40,
  "targetsCompleted": 38,
  "targetsFailed": 2,
  "targetsBlocked": 0,
  "targetsBudgetLimited": 0,
  "rowsObserved": 78,
  "rowsSaved": 78,
  "rowsUnchanged": 0,
  "requests": 44,
  "historyEnabled": true,
  "historyCommitted": true,
  "targets": [
    { "target": "https://www.cosrx.com/products/advanced-snail-96-mucin-power-essence", "status": "completed", "reason": null, "observed": 3, "saved": 3, "unchanged": 0, "requests": 2 },
    { "target": "https://www.ikea.com/us/en/p/billy-bookcase-white-00263850/", "status": "failed", "reason": "Ambiguous products; target has no matching canonical URL", "observed": 0, "saved": 0, "unchanged": 0, "requests": 1 }
  ]
}

Each target also has checkCharged (true when this URL was billed), and the record has a charging object with the number of charged events and whether your maximum cost was reached.

URL status	Meaning	Charged
completed	Page read, rows stored (or all unchanged with onlyChanges).	Yes
partial	Read, but cut by maxItems or the 250-variant Shopify limit.	Yes, if at least one row was stored or found unchanged
failed	No usable product data (reason given), HTTP error, or conflicting prices.	No
blocked	The site answered HTTP 403 or 429.	No
budgetLimited	Not reached within maxRequests, maxRunSeconds or your maximum cost.	No

The run itself fails only when every URL failed.

Change tracking

• Without historyStoreName every run is an independent snapshot: all rows have isNew: true.
• With it, the Actor keeps the last saved observation of each variant (a hash, price and currency, not the page text) in a key-value store of that name in your account.
• isChanged is true when any field of the row differs: price, stock status, title, SKU and so on. priceChange is filled only when both prices have the same known currency.
• onlyChanges: true stores only new or changed rows. A quiet day gives zero rows; RUN_SUMMARY.rowsUnchanged shows how many were checked and identical.
• Only rows that were stored move the baseline. If a dataset write fails, the history is not advanced and the run fails.
• Use one history name per product list, and do not run two runs with the same name at the same time. Up to 10,000 variants are remembered per history. Changing a URL starts a new record.

Pricing

Pay per event: $0.003 for each product URL that was checked successfully (event name target-check), plus the standard Actor start event ($0.00005 per run). Rows are free: a URL with 12 variants costs the same as a URL with one.

What you run	Checks	Cost
10 URLs, once	10	$0.03
50 URLs, every day for 30 days	1,500	$4.50
100 URLs, every day for 30 days	3,000	$9.00
500 URLs (5 runs), once a week for 4 weeks	2,000	$6.00

Not charged: URLs that end as failed, blocked, budgetLimited or notStarted; dataset rows; the run summary.

Good to know:

• With onlyChanges, a URL that was checked and found unchanged is still one check. The check is the work.
• If you set a maximum cost per run, URLs that no longer fit are not fetched and end as budgetLimited. RUN_SUMMARY.charging.chargedEvents equals the number of URLs with checkCharged: true.

Reliability: what we measured

One cloud run on 2026-10-02, 256 MB, no proxy, 40 product URLs on 9 stores, one request per second:

Store type	URLs	Read	Notes
Shopify (6 stores)	31	31	29 by JSON-LD, 2 by Shopify fallback (the page had conflicting JSON-LD prices)
Other stores with JSON-LD (3 stores)	9	7	2 pages failed: no JSON-LD on the page, or several products without a matching URL
Total	40	38 (95%)	78 variant rows, 44 requests, 57 seconds, no HTTP 403/429

A second run with onlyChanges on the same URLs stored 0 rows and reported 78 unchanged.

This is a small same-day sample on stores that do not block data-center traffic. Stores with bot protection will be blocked.

Limits and honest notes

• No proxy, no browser, no cookies. Sites that block data-center IPs or need JavaScript for the price are not supported.
• Listed prices only. Shipping, tax, coupons at checkout, member prices and marketplace seller offers are not included.
• No automatic product matching. The Actor does not decide that two pages sell the same item. You link them with productCode.
• Conflicting data fails. If a page publishes two different prices for the same variant and is not a Shopify storefront, the URL fails instead of guessing.
• Requests are sequential, at least 500 ms apart, with no automatic retries. 100 URLs take about 2 to 4 minutes.
• Up to 100 URLs per run. Split larger lists into several runs or tasks; they can share one history name if they do not run at the same time.
• Shopify returns at most 250 variants per product.
• The robots-disallowed Shopify /cart.js endpoint is never requested; currency is read from the product page.

Use from the API

curl -X POST "https://api.apify.com/v2/acts/magenta_courser~brand-price-stock-monitor/run-sync-get-dataset-items?token=YOUR_TOKEN" \
  -H "Content-Type: application/json" \
  -d '{"products":["https://sokoglam.com/products/cosrx-advanced-snail-96-mucin-power-essence"],"historyStoreName":"my-brand-prices"}'

Schedule it in Apify Console (Schedules) or call it from n8n, Make or Zapier with the same JSON.

Use with AI agents (MCP)

The Actor works as a tool through the Apify MCP server. One required input (products, a list of URLs), flat output fields, numbers as numbers and null for unknown values. A good instruction: "Check these product URLs with brand-price-stock-monitor and list variants where available is false or priceChange is negative."

FAQ

Does it find resellers for me? No. You supply the product page URLs.

Why did my URL fail with "No public Product JSON-LD found"? The page does not publish machine-readable product data and is not a Shopify storefront. It cannot be read without a browser.

Why blocked? The site refused the request (HTTP 403 or 429). There is no proxy option. Blocked URLs are free.

Can I track thousands of URLs? Yes, in runs of up to 100 URLs. Remember that one history keeps up to 10,000 variants.

Is a missing row a sold-out product? No. Sold-out variants are rows with available: false. A URL that could not be read has no rows and a failed or blocked status in RUN_SUMMARY.