CS2 skin price alerts

The one tool here that needs a server

Every other tool on this network runs entirely in your browser, and that is a deliberate design rule. This one breaks it, for a reason worth stating plainly: the whole point is to watch a price while you are not here. A closed tab cannot poll a market or send an email. Watching for you is the product.

So this site has a small backend — a Node process, a Postgres table and a loop. It stores the minimum that job requires: your Steam ID, the skin name, your threshold and the email address to notify. No inventory access, no trade permissions, no browsing history.

How the Steam login works

Steam uses OpenID 2.0, which means the login page is Steam's own, on Steam's domain, and your password never touches this site. When you come back, Steam includes a signed claim of your identity, and we hand that claim straight back to Steam asking whether it really issued it. Only if Steam says yes does a session get created.

What we receive is a 17-digit Steam ID and nothing else. This flow needs no API key and grants no permissions over your account — it cannot read your inventory, cannot trade, and cannot post anything.

Why alerts start as pending

Any form that takes an email address and later sends mail to it can be pointed at someone else's inbox. That is why the first message you receive is a confirmation link and the alert sits inactive until you click it. It costs you one click and stops the service from becoming a way to send unsolicited mail to strangers.

The price history chart, and where it comes from

Click any alert in your list to see the price series for that skin. The data is Valve's own: it is the same official Steam Market price endpoint that drives the alerts.

What it is not is the full historical series Steam shows on the item page. That endpoint (/market/pricehistory/) requires a logged-in account session cookie and returns 400 without one — keeping a Steam account logged in on a server purely to scrape it is not something we will do. So the series here is built from our own readings: it starts empty for a new skin and gains a point at each check where the price moved. An item tracked for a week has a week of chart.

Rate limits, and what they mean for you

Steam's public price endpoint is aggressively throttled — a few requests per minute before it starts refusing. Two consequences follow, and both are worth knowing before you rely on this:

• Checks are spaced. Each alert is re-checked about every half hour rather than continuously. For a sharp spike that lasts minutes, you may get the email after the moment has passed.
• Prices are shared. Every fetched price goes into a cache keyed by skin and currency, so many people watching the same item generate one request between them. This is what lets the service scale at all under those limits.

If you need second-by-second precision on a fast-moving item, no email-based alert service can give you that — you need to be watching the market yourself.

Getting the name right

Steam matches on the exact market hash name, and it is unforgiving. The wear is part of the name in parentheses, and StatTrak™ and Souvenir are prefixes, not flags. The builder above assembles all three in the right order, but the safest approach is to copy the title straight from the item's Steam Market page.

What we store, precisely

Your Steam ID, the skins and thresholds you set, the email address you gave, and the last observed price for each alert. Delete an alert and its row goes with it. There is no tracking, no profiling, and the email address is used for nothing except the confirmation and the alert itself.