01 The short answer
League of Legends companion apps that read champ select and import a rune page are doing something you could do yourself in the client, just faster. They don't touch the game, they don't inject anything into it, and they don't play it for you. That category has run in the open for years: Warden works this way, and so do Blitz, Porofessor, Mobalytics and OP.GG. If you want the tour of what's out there, we compare them in the best League companion apps.
What gets accounts banned is a different category entirely, and the difference is worth understanding rather than guessing at.
02 What Riot's policy actually says
These apps talk to the League Client through what's called the LCU API, and Riot publishes a policy for it. Three parts matter.
Developers have to register. In Riot's words: Before you
release an application (or an update to your existing
application) that uses the League Client API in any region, you
must contact us and let us know.
There's also an approved
endpoint list, and only endpoints on our approved list are
allowed for use by developers.
And there's a regional exception that a lot of app pages don't
mention: For the time being we will no longer allow players in
Korea to use applications leveraging the League Client API.
That applies to the whole category, not to any one app. If you
play on KR, this is the part to know about.
Worth being straight about the rest: that policy is written for developers, and it doesn't say anything about penalties for players. We're not going to fill that silence with a promise we can't make. What we can say is what the tools do and don't do, which is the part you can actually judge.
03 Where the line sits
The distinction Riot has enforced consistently is between reading information the client already gives you and interfering with the game itself.
- Reading champ select and building a rune page. This is what every companion on the market does, including Warden. Nothing enters the game process.
- Scripting. Automated dodging, last-hitting, combos, skillshot dodging. This is what bans are for, and it's not a grey area.
- Anything reading or writing game memory. Map hacks, fog-of-war removal, cooldown trackers that read the process rather than the client.
- Automating account actions. Bots that queue, accept and play unattended.
Companion apps sit firmly in the first bucket. Everything below it is a different product doing a different thing, and no amount of "but it's just a tool" changes which side of the line it's on.
04 What Warden does, precisely
Worth spelling out, because "trust us" isn't an answer. Warden connects to the League client already running on your PC and reads the champ select state: your champion, your role, the queue. That's the input.
The output is a rune page and an item set, created through the same client interface you'd use by hand, named so you can see which ones it made. It never deletes or overwrites a page it didn't create. It doesn't attach to the game process, doesn't read game memory, doesn't modify game files, and doesn't do anything at all once the loading screen starts.
There's no Warden account and nothing is uploaded, so there's no profile of your play sitting on a server somewhere either. It also runs on its own, with no Overwolf client underneath it, so there's only one piece of software to judge: 26 MB, and that's the whole install.
The honest take
If you're asking this question because you saw a Reddit thread and got nervous, the thing to check isn't the app's marketing. It's whether it touches the game or only the client. Warden only ever touches the client.
And if you play on KR, Riot's policy says this whole category is off the table for you, ours included. We'd rather tell you that here than take the download.