Microsoft said in December 2020 that its Xbox Cloud Gaming service would be coming to PC sometime in the first half of 2021, allowing Game Pass subscribers to instantly stream games rather than having to download them first Today it followed through on that promise, to a limited extent at least, announcing that beta test invitations will start going out to "select" Xbox Game Pass Ultimate subscribers tomorrow, April 20.
"The limited beta is our time to test and learn; we’ll send out more invites on a continuous basis to players in all 22 supported countries, evaluate feedback, continue to improve the experience, and add support for more devices," Microsoft said. "Our plan is to iterate quickly and open up to all Xbox Game Pass Ultimate members in the coming months so more people have the opportunity to play Xbox in all-new ways."
There are a few qualifications (aside from being a Game Pass Ultimate subscriber) required in order to take part in the test. Access to the service will be supported through either the Edge or Chrome browsers (or Safari if you're on an iOS device—the beta is also coming to Apple phones and tablets), and you'll need a controller, either wired or Bluetooth, or "custom touch controls" for the games that support them on iOS.
Microsoft said that the early stage of the test will be dedicated to "fine-tuning features and creating a consistent experience across platforms, while making sure games are running their best." More than 100 Xbox Game Pass games will be available through the cloud, and more invitations to the test will be sent out in future waves.
An FAQ clarifies that there's no option to sign up for access to the beta—batches of invitations will be sent to existing Xbox Game Pass Ultimate subscribers via email. More information on the beta is available through the Xbox Cloud Gaming Support Hub on Reddit.