Amazon Seller Alerts — Real-Time Buy Box & Hijacker Notifications | SentryKit

Buy Box Intelligence Platform

You lost $247 today.
You reversed it in 90 seconds.

Most sellers find out hours later — after the damage is done. SentryKit alerts arrive before you open your dashboard: who caused it, what it's costing, and three ranked options to recover.

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82%

of all Amazon purchases
go through the Buy Box

30 days free

to start — full monitoring available

4 threat areas

Buy Box, hijackers,
inventory, listing health

What a SentryKit Alert Looks Like

Not just "something changed."
Who. What it costs. Exactly what to do.

Every alert delivers the context you'd otherwise spend 20 minutes digging for — before you've opened your dashboard. Pick a scenario below.

Buy Box Lost

Competitor took it · $22.9/day

Hijacker Detected

Unknown FBM · 30% below

Out of Stock

FBA zero · restock in transit

Sales Volume Up

Sales up 71% ~5 days of stock cover

Price Floor Breach

$1.50 lost per unit

Buy Box Suppressed

Amazon removed it entirely

And many more:

Competitor Price Change

Tracked competitor moved

Low Stock

Approaching your threshold

Margin Threshold

Margin fell below target

Content Changed

Title or image modified

Delivery

Alerts where you already work

Every signal SentryKit fires can reach you on your preferred channel — no dashboard required.

Rich alert emails with KPI cards, ranked options, and signal detail — delivered within 90 seconds.

Google Sheets

Every alert auto-appends a new row — timestamp, ASIN, alert type, and key metrics. Your live ops log.

Slack

Direct Slack integration — alerts posted to your channel the moment they fire, no relay needed.

Zapier

Connect alerts to 7,000+ apps — trigger workflows in your existing tools the moment an alert fires.

Intelligence That Compounds

Same alert.
Sharper signal every day it runs.

Day 1 you get the event. Day 30, you get context. Day 60, the alert knows whether you even need to act — because it's learned your catalog's patterns.

Day 1 Event + context

Day 30 Baseline visible

Day 60 Patterns known

Full Alert Coverage

Every signal that moves your revenue.
Nothing missed. Nothing late.

Real-time for what's urgent. Digest for what needs context. Every alert tells you what happened, what it costs, and what to do next.

Buy Box

Buy Box Lost

Who took your Buy Box — and the exact revenue you're losing per day

Fires within ~90 seconds via SQS push. Includes the competitor's price, your gap to them, floor room available, and three ranked options to recover.

Buy Box Suppressed

Your Buy Box was removed entirely — no competitor holds it, no repricer fixes it

Amazon removed it due to a listing or pricing issue. Not the same as Buy Box Lost — the cause and the fix are completely different. SentryKit keeps them separate so your response is correct.

Competitor Price Change

A tracked competitor moved their price — know before your repricer reacts

Set your own threshold. Fire when a competitor crosses it — so you decide how to respond, rather than finding out after your repricer has already chased them down.

Pricing & Margin

Price Floor Breach

Your price dropped below your landed cost floor — every sale is now costing you money

Floor = COGS + FBA fees + inbound + your margin target. FBA fees auto-update from SP-API. The alert shows exactly which cost component drove the breach so you know what to fix.

Margin Threshold

Your margin on an ASIN fell below your target — before more units sell at a loss

Set a minimum margin percentage per ASIN. SentryKit fires when your effective margin falls below it, calculated live against current fees, price, and your cost inputs.

Competitive Intelligence

Hijacker Detected

An unknown seller appeared on your branded listing — before your repricer matches their price

Fires the moment an unauthorized seller appears. Profile includes fulfillment type, feedback score, and listing count. Full Zyte seller enrichment available for instant IP and cease-and-desist assessment.

Inventory & Sales

Out of Stock

FBA stock hit zero — including pending transshipment units most tools don't see

Stock calculated as fulfillable + pending transshipment — so this only fires on a true stock-out. Includes whether a restock is already in transit and the estimated arrival window.

Low Stock

Inventory is falling toward your threshold — time to restock before Buy Box eligibility drops

Set your own minimum per ASIN. Fires when FBA stock falls below it, giving you lead time to replenish before a stock-out silently removes you from Buy Box contention.

Sales Volume Up

Sales spiked above your threshold — your stock cover may be shorter than it looks

A velocity surge is good news until your stock cover quietly collapses. Fires when sales exceed your threshold so you can restock before the momentum stalls out.

Sales Volume Drop

Sales fell below your threshold — and the causal signal is surfaced alongside it

Set your drop percentage and rolling window. When triggered, the alert includes concurrent Buy Box status, ownership trend, and ranked options to help you diagnose fast.

Listing Signals

Content Changed

Your title, main image, or category was modified — by Amazon, a co-seller, or an error

Detected through SP-API catalog data. Surfaces in your morning digest with what changed, what it was before, and whether action is required to restore your listing.

Badge & Add-to-Cart Changes

Amazon's Choice, Best Seller, or Add to Cart status changed on your listing

Badge gains and losses directly affect conversion rate — often without any obvious cause. Surfaces the change so you can correlate it with sales impact and act before it compounds.

Daily Portfolio Digest

Your full catalog, briefed in one email every morning

Buy Box win rate across all ASINs, revenue at risk today, low stock flags, and top competitor movements. Free tier: held Tier 1 alerts are delivered here.

BB win rate across all ASINs
Revenue at risk today
Low stock and stock-out flags
Free tier: held critical alerts delivered here

Every hour without monitoring is revenue at risk

Real-time alerts from $19/mo.

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Frequently Asked Questions

Tier 1 critical alerts — Buy Box Lost, Buy Box Suppressed, Hijacker Detected, Out of Stock — fire within approximately 90 seconds of the event via Amazon SQS push notifications. This is a push architecture, not polling. SentryKit doesn't check your listings every few hours. Amazon pushes the event the moment any offer changes, and SentryKit processes and delivers it immediately.

Buy Box Lost means a competitor is now holding your Buy Box — there's a winner and it isn't you. Buy Box Suppressed means Amazon has removed the Buy Box from your listing entirely — no seller holds it. The cause and the fix are completely different, which is why SentryKit treats them as separate alerts.

A repricer reacts to price — it doesn't know why someone appeared or who they are. SentryKit's hijacker alert fires the moment an unauthorized seller appears on your branded listing and includes their fulfillment type, feedback score, and listing count. Full Zyte enrichment gives you the seller profile you need for an immediate IP or cease-and-desist response.

Tier 1 real-time alerts (Buy Box Lost, Buy Box Suppressed, Out of Stock) are held on the free plan and delivered in your daily morning digest. Immediate push delivery — email, Slack, Sheets, Zapier within 90 seconds — requires a paid plan starting at $19/mo. The 30-day free trial gives you full access to all real-time alert delivery across every channel.

Yes. SentryKit monitors your entire catalog across all connected marketplaces. Each ASIN gets its own alert configuration — you can set different thresholds per product. The daily digest gives you a portfolio-level view across everything, while real-time alerts fire per ASIN the moment an event occurs.

You lost $247 today.You reversed it in 90 seconds.

Not just "something changed."Who. What it costs. Exactly what to do.