E-Commerce Price Tracker — Amazon & Shopify Price, Rank & Review Velocity

One scan per product. Tracks the four signals every e-commerce operator monitors daily: price, stock, category rank, and review velocity. Works on Amazon ASINs and any Shopify store.

If you sell on Amazon, run a brand on Shopify, do MAP enforcement, run a repricer, or watch competitors — you already check these four signals every morning. This actor does it for you, returns structured JSON plus a markdown report, and tells you what changed since your last scan.

What this scan returns per product

Amazon products (ASIN-based):

• Current price (deal price, sale price, or buy-box price)
• List / strike-through price + computed discount %
• Availability + Buy Box seller + Prime eligibility
• Star rating and total review count
• Review velocity — new reviews in the last 30 and 90 days (sampled from recent reviews sort)
• Best Sellers Rank for primary and sub-categories
• Variations (color/size), image count, top feature bullets, breadcrumb category path
• Delta vs your last scan: price change, BSR change, new reviews, availability flips

Shopify products (any Shopify-powered store, custom domain or .myshopify.com):

• Current price + compare-at price + discount %
• Stock status, vendor, product type, tags
• All variants with prices and stock state
• Image count, creation/update timestamps, description body
• Delta vs your last scan: price moves, new variants, stock changes

Bonus: an AI-written executive narrative for each product, plus a fully formatted markdown intelligence report — ready to paste into Slack, a spreadsheet, or a client deliverable.

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Who uses this

• Amazon sellers — monitor your own listings + competitor ASINs in the same run
• Brand owners doing MAP enforcement — alert when a reseller drops below your floor
• Repricer feeds — pipe the JSON dataset directly into your repricing logic
• Investors — track BSR drift on the products driving a portfolio company's revenue
• Competitive intel teams — watch 200 SKUs across Amazon and Shopify in one run
• Agencies — sell a "price + rank + review velocity dashboard" deliverable without building the scraper

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Why this is different

Most price scrapers only return price. This one returns the operating dashboard for a product:

• Price tells you where you are. Rank delta tells you whether you're winning.
• Review count tells you total volume. Review velocity tells you whether the listing is gaining or losing momentum right now.
• Stock status tells you availability. Stock change vs last scan tells you whether a competitor just sold out or restocked.

Run on a schedule (daily or weekly) and you have a full e-commerce intelligence feed — at $0.90 per product scan.

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Input

{
    "products": [
        { "url": "https://www.amazon.com/dp/B08N5WRWNW", "label": "Echo Dot 4th gen" },
        { "url": "https://www.amazon.co.uk/dp/B07YH8E4SV" },
        { "url": "https://shop.example.com/products/blue-widget", "label": "Competitor Blue Widget" }
    ],
    "maxReviewsForVelocity": 25,
    "reportStyle": "full"
}

Field	Required	Default	Description
products[].url	Yes	—	Product URL. Amazon /dp/ASIN or any Shopify /products/handle
products[].label	No	—	Your internal name for the product (echoed back in output)
products[].platform	No	auto	amazon or shopify — auto-detected from URL if omitted
maxReviewsForVelocity	No	25	Amazon-only: how many recent reviews to scan for velocity (5–100)
reportStyle	No	full	full (detailed markdown) or brief (one-liner)

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Output — one record per product

Amazon record (excerpt)

{
    "platform": "amazon",
    "asin": "B08N5WRWNW",
    "title": "Echo Dot (4th Gen)",
    "brand": "Amazon",
    "price": 29.99,
    "currency": "$",
    "listPrice": 49.99,
    "discountPct": 40,
    "availability": "In Stock",
    "stars": 4.7,
    "reviewCount": 612843,
    "buyboxSeller": "Amazon.com",
    "prime": true,
    "bsr": [ { "rank": 12, "category": "Smart Home" } ],
    "reviewVelocity": { "reviewsLast30d": 8, "reviewsLast90d": 22, "recentSampled": 25 },
    "changeSinceLastRun": {
        "priceDelta": -3.00, "pricePctChange": -9,
        "reviewCountDelta": 142,
        "bsrPrimaryDelta": -4,
        "availabilityChanged": null
    },
    "aiNarrative": "Echo Dot (4th Gen) is currently at $29.99 (In Stock). Discount of 40% off list price. Rated 4.7/5 across 612,843 reviews. Price moved down by 3.00 (-9% vs last run). Picked up 142 new reviews since last run. Category rank improved: #16 → #12 (-4). Review velocity: 8 in last 30 days, 22 in last 90 days. Best Sellers Rank: #12 in Smart Home.",
    "intelligenceReport": "# Product Scan Report — Echo Dot…\n…"
}

Shopify record (excerpt)

{
    "platform": "shopify",
    "title": "Blue Widget",
    "brand": "ExampleBrand",
    "handle": "blue-widget",
    "price": 24.00, "listPrice": 30.00, "discountPct": 20,
    "availability": "in_stock",
    "variants": [
        { "title": "Default", "price": 24.00, "available": true }
    ],
    "changeSinceLastRun": { "priceDelta": -3.00, "pricePctChange": -11 },
    "aiNarrative": "Blue Widget is currently at $24.00 (in_stock). Discount of 20% off list price. Price moved down by 3.00 (-11% vs last run).",
    "intelligenceReport": "# Product Scan Report — Blue Widget…\n…"
}

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Pricing

$0.90 per product scan (pay-per-event). One product in products = one scan = one charge.

That is cheaper than every Amazon-only price tracker on the market and includes Shopify, review velocity, BSR tracking, and the delta-since-last-run feature.

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Common workflows

• Daily MAP enforcement: schedule daily across 50 reseller URLs → filter price < your_map → push to Slack
• Repricer feed: schedule every 6 hours on your competitor ASINs → consume price field via webhook
• BSR drift alert: weekly schedule → alert when bsrPrimaryDelta > 500 (rank worsening fast)
• Launch velocity tracker: scan your new launch + 3 competitors daily for 30 days → graph reviewVelocity.reviewsLast30d
• Cross-channel pricing audit: scan your own product on Amazon AND your Shopify in one input → flag pricing inconsistency

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Tips

• Amazon multi-region: works on amazon.com, amazon.co.uk, amazon.de, amazon.ca, amazon.com.au, amazon.co.jp etc — the actor uses the request host to fetch reviews from the matching domain
• Shopify .json endpoint: the actor uses <url>.json first (no scraping, no rate-limit risk). If the store has disabled the JSON endpoint, it falls back to DOM scraping
• Review velocity is sampled — set maxReviewsForVelocity: 50+ for higher-traffic listings where you need a stable 30-day count

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Limits & honesty

• Amazon shows different prices to different users. This actor scrapes the page-as-served — most often the standard logged-out US price. For per-region or per-cart pricing, run multiple scans with the relevant regional URL.
• BSR is read from the page text — Amazon occasionally omits BSR for some categories. When absent, the field returns [].
• Shopify stock: the JSON endpoint reports per-variant availability boolean — the actor reports the first variant's state in availability, and the full list in variants.

Built and maintained by Johnson AI Consulting — see also our Amazon Product Intelligence actor, Review Intelligence Agent, LinkedIn Company Monitor, and Competitor Intelligence Monitor.