SlowDen › Blog › Why a portal thinks your game is dead
We checked all 249 games on our shelf. 13 point at URLs that no longer work, and 3 were fine but looked broken to us. Both are avoidable.
We check every game on our shelf automatically. Today we checked all 249 of them and then, unusually, checked the checker. Both halves are worth passing on.
14 of 249 listings (5.6%) point at a URL that no longer serves anything — a 404, a 403, a 503, or a host that does not answer at all.
Four days earlier that number was 7. It is rising, and the reason is mundane: nothing re-checks a URL after the day it is approved. A game goes up, the listing is correct, and then months later the hosting changes and nobody is watching.
The pattern underneath most of them: a URL that was never meant to be permanent. Preview deployments, free tiers that sleep or expire, and build-specific URLs carrying a version parameter. One in this set was live and correct when we verified it, and returned 404 the next morning.
If you are submitting a game anywhere, submit a URL you intend to keep. A plain path on a domain or project you control will outlive a preview link by years.
This is the one almost nobody writes about, so here it is with the numbers.
Our check flagged 64 games as unplayable in an embed. We
re-checked every one of them by hand, sending the same request a browser would send — a normal
User-Agent and Accept header. 60 were
genuinely blocked. 3 were not blocked at all.
| Our automated check | Games |
|---|---|
| Said "blocked" | 64 |
| Genuinely blocked | 60 |
| Fine — we were wrong | 3 |
Those 3 answered 403 Forbidden to our request and 200 OK
to the identical request carrying browser headers. They run bot protection. An automated check with
no User-Agent looks exactly like a scraper, so it got the scraper's answer.
From the developer's side this is invisible. The game works every single time you test it, because you test it in a browser. The portal quietly decides it is broken.
One command. Request your own game the way an automated checker would — with no headers:
curl -sS -o /dev/null -w "%{http_code}\n" https://your-game-url/
Then the way a browser does:
curl -sS -o /dev/null -w "%{http_code}\n" -A "Mozilla/5.0" https://your-game-url/
If the first returns 403 and the second returns 200, your host is filtering bots and some portals will read that as a dead game. It is worth knowing before it costs you a listing.
Our checker now sends browser headers, and treats 429 Too Many Requests as "ask
again later" rather than "broken" — we were rate-limiting ourselves by checking several games on
one host in quick succession and then believing the result.
We would rather say that plainly than quietly fix it. If an automated check decides whether people can play your game, the check itself has to be held to a standard.
Related reading: how many browser games refuse to be embedded and why your game breaks inside an iframe.
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