Steam Deck Verified will show you how "the entire Steam catalog" plays on the handheld

Steam Deck Verified is Valve's newly announced way of evaluating how well Steam games play on its upcoming Steam Deck handheld. 

Valve unveiled this corner of the Steam Deck compatibility program today, describing Steam Deck Verified as a four-tier grading system. Here's how Steam games will be ranked under this new system:

• Verified: for games that play well on Steam Deck without any additional setup. Ghostrunner is highlighted in Valve's announcement, but many more games already fit this criteria.
• Playable: these games "may require some manual tweaking" to play well on Steam Deck, Valve says. The company points to Team Fortress 2 as one example. 
• Unsupported: these games are totally unplayable on Steam Deck. Half-Life Alyx, a VR exclusive, is an obvious example here.
• Unknown: Valve has yet to evaluate these games for Steam Deck playability. There are a zillion games on Steam, so expect to see this rating pretty often, especially while Steam Deck Verified is still getting off the ground. 

A game has to check four key boxes to earn a Verified grade. The Steam Deck is basically a handheld gamepad with a screen on it, so Verified games will need full controller support with fitting icons, for one, as well as on-screen keyboard support. Their display settings will also need to accommodate the Steam Deck's default resolution of 1280x800 (preferred) or 1280x720 (minimum) without mangling text legibility.

Every part of a Verified game, from launchers to anti-cheat support, will also have to be compatible with Proton, the Windows compatibility layer that bridges gaps between some games and Steam Deck's Linux operating system. And finally, Verified games mustn't have any compatibility warnings – part of Valve's more nebulous criteria for "seamlessness." 

Valve says it's already begun the herculean task of evaluating "the entire Steam catalog on Deck" and will display compatibility ratings via the Steam Store on the handheld, with a dedicated "Great on Deck" tab highlighting Verified games. 

"You'll be able to see Steam Deck compatibility details for every title that has been reviewed, giving you the information you need to inform your playing and purchasing decisions," Valve says. This should also make it easier to see how well your existing Steam library would play on the handheld. 

Valve advised that a game's rating may change over time, so we're sure to see some fluctuations as games and the Steam Deck are tweaked. The review process FAQ states that developers can update their game and request a re-evaluation to improve their Steam Deck rating, for instance. Valve expects each review process to be turned around "within a week of submission," but acknowledged that this time frame will change "based on the current size and complexity of the other titles in the queue." 

Here's an encouraging frontrunner for Valve's handheld: The Witcher 3 looks seriously good on Steam Deck.