Competitor Price Monitor - Product Matching & Stock Alerts

Monitor public Shopify catalogs and product-page Schema.org JSON-LD for price, promotion, and stock-availability changes. The Actor emits one dataset row per deduplicated offer or variant and keeps run notices and summaries in the default key-value store.

Why this monitor is different

• Identifier-first matching: exact GTIN, or exact brand plus MPN/model.
• Explicit variant and pack conflicts abstain instead of forcing a false match.
• ProductGroup pages emit their real size, color, pattern, and material variants without an extra group-summary offer.
• Price, currency, availability, and structured unit evidence remain separate so an inferred unit price is never presented as observed data.
• Partial collection is disclosed and never used to infer removals.

Product titles and merchant-local SKUs do not establish identity. Unknown or unsupported currency is null; do not compare prices across observations unless both rows have the same explicit currency. Unit and pack matching is used only when structured source data and reference fields make it explicit.

Inputs

Use either stores for public Shopify roots or productUrls for public HTTPS product pages. The two modes cannot target the same host in one run. Tracking parameters, fragments, duplicate URLs, and store path variations are normalized before monitoring. referenceProducts accepts GTIN or brand plus MPN/model, with optional variant, packSize, and packUnit conflict guards. monitoringKey gives a monitor a stable customer-defined baseline scope.

The default input monitors https://www.allbirds.com/products/mens-strider-explore with monitoringKey: "default" and returns at most 25 observations. Collection supports up to 20 stores, 100 product URLs, 1,000 reference products, 10,000 catalog products per store, and 20,000 delivered observations.

Output and history

Dataset rows are offer observations. STATUS, SUMMARY, and OUTPUT in the default key-value store describe completion, partial sources, first-seen/changed/unchanged counts, and nonbillable notices. A partial run preserves prior unobserved offers and does not infer removals.

History assumes the same actor, user, normalized input configuration, and monitoringKey. Changing that scope starts a different baseline. Source data can change between requests, and public catalogs do not provide inventory counts. Shopify availability is an availability signal only.

Billing

A valid run start costs $0.03 and each delivered offer observation costs $0.03. The default maximum is $0.78: one $0.03 start plus up to 25 observations at $0.03 each. Free and paid Apify users receive the same inputs, collection limits, and result fields. Invalid input and KVS notices are not observation events.

Dataset storage and event charging are separate Apify operations, so exactly-once delivery is not guaranteed if storage, charging, or the run fails between those operations. A billing limit or delivery failure stops further observations and prevents an unsafe baseline replacement.

Support limits

Only public HTTPS Shopify catalog JSON and server-visible Schema.org product JSON-LD are supported. JavaScript-rendered content, logins, CAPTCHA or anti-bot bypass, private APIs, exact inventory counts, and universal merchant coverage are outside scope. The network client rejects credentials, custom ports, IP literals, private/link-local/metadata addresses, and unsafe redirects.

This Actor is unofficial and is not affiliated with Shopify, Allbirds, or any monitored merchant.