Stock Monitor
Cassian Sentinel™ alerts you when a tracked product sells out, and projects low-stock warnings before it happens. Available on WooCommerce and BigCommerce.
A product that quietly sells out stops earning until someone notices. Stock Monitor, part of Cassian Sentinel™, watches your tracked inventory daily and tells you when a variant hits zero — and, where enough history exists, warns you before it does.
Stock Monitor is available on WooCommerce and BigCommerce only. Shopify does not grant inventory-tracking data under Cassian™'s read-only permission set (the read_inventory scope is not requested), and Wix is not supported. If your store is on Shopify or Wix, stock monitoring will show as unavailable — this is expected, not a fault.
What Stock Monitor Detects
| Alert | Trigger |
|---|---|
| Stock-out | A tracked variant's quantity reaches zero. The one fact-based stock alert — no projection involved. |
| Low stock | The projected days-to-stockout falls at or below your threshold, based on the variant's sales velocity over the trailing 14 days. |
Low-stock projections need at least 7 days of inventory history before they switch on — a shorter window is too thin to trust a trend. The projection also resets when you restock mid-window, so velocity is measured from the restock forward, not blurred across it.
No Separate Toggle
Stock Monitor has no toggle of its own. On WooCommerce and BigCommerce, it's enabled automatically alongside Pricing Pulse — inventory is read in the same daily check that reads your prices, at no extra setup. See Pricing Pulse for how that run is scheduled.
Tier Depth
| Plan | Coverage |
|---|---|
| Inspector | Stock-out alerts on your top sellers only. No low-stock projections. |
| Analyst and above | Stock-out alerts on all tracked variants, plus low-stock projections. |
"Top sellers" means variants with recorded sales in the trailing 30 days.
Sensitivity
Your per-site sensitivity preset (Settings → Alert controls) tunes how early and how broadly Stock Monitor fires:
| Preset | Low-stock threshold | Scope |
|---|---|---|
| Relaxed | — (low-stock off) | Stock-outs on top sellers only |
| Normal | ≤7 days projected | Stock-outs on all tracked variants; low-stock on top sellers |
| Sensitive | ≤14 days projected | Both alerts on all tracked variants |
Tier limits and presets combine — whichever is more restrictive wins. See Alerts & Incidents for how presets work across all monitors.
One Alert per Episode
Stock Monitor fires once per stock-out episode. You're alerted when a variant sells out; you are not re-alerted every day it stays at zero, and there is no "restocked" recovery notification — when you restock, the incident resolves silently and the monitor re-arms for the next episode. This is deliberate: stock chatter is the classic source of alert fatigue.
Frequently Asked Questions
Why can't Cassian monitor stock on my Shopify store?
Cassian requests read-only Shopify permissions, and Shopify puts inventory-tracking data behind a separate read_inventory scope that Cassian does not request. Without it, a quantity of "0" can't be distinguished from "not tracked", so Cassian declines to guess. Pricing Pulse still works fully on Shopify.
I just connected my store — why no low-stock warnings yet? Low-stock projections need about 7 days of inventory history to establish a sales velocity. Stock-out alerts work from day one.
A variant sold out and came back — will Cassian tell me it's back? No. There is no restock notification by design. The incident resolves on the Alerts page, and the variant is watched again for its next stock-out.
Does Stock Monitor count untracked inventory? No. Variants without inventory tracking enabled on your platform are ignored — an untracked "0" doesn't mean out of stock.
Where do stock alerts appear? On the Alerts page alongside every other monitor, delivered through your configured notification channels. Stock-outs and low-stock warnings respect quiet hours and per-channel severity floors like any other alert.