Read this first — this is not Microsoft software

• This is an independent client. It is not made by, endorsed by, or affiliated with Microsoft or Xbox.
• To reach a game session it authenticates using Microsoft's own web-client identifier. The Microsoft consent screen you are about to see will therefore name Microsoft's client, not this site. That is why you are being told here instead.
• Your password is entered on Microsoft's own page and never reaches this server. The session tokens it issues do pass through this server in order to start a stream.
• Third-party clients like this one are tolerated rather than authorised. Tolerance can end without notice. Any consequence lands on the account that signs in — yours.
• You need Xbox Game Pass Ultimate. Nothing here grants access to games.