Valve announced that it would review the entire Steam catalog after announcing the Steam Deck and determine the compatibility of games with steam deck.

Each game reviewed will be placed in a category based on its compatibility with steam deck;

The categories are as follows:

Confirmed: The game works perfectly on the Steam Deck without doing anything.

Playable: The user may need to make some settings for the game to be playable.

Not supported: The game currently doesn’t work on the Steam Deck.

Unknown: We haven’t checked the compatibility of this game yet.

Here are the first results of these studies appeared, and some games began to receive Steam Deck compatibility. For now, these can be seen via SteamDB and not on the Steam store page, but it’s also possible to show them on the Steam Store page with a little trick. There are only 67 games with this information, the number will increase rapidly by the day.

For example, Cuphead appears as Confirmed, while The Witcher 3: Wild Hunt appears to be Playable.

As you can see, the substance that affects Steam Deck compatibility is that some in-game interface text is difficult to read because it is small. Such incompatibilities will probably be resolved through patches.