Link 's Steam account. Paste a profile URL (steamcommunity.com/id/… or /profiles/…) or the vanity name.
Steam only shares the game list if the profile's Game details privacy setting is Public (Steam → Profile → Edit Profile → Privacy Settings).
Anyone with this link can browse this library read-only — every game, its details and notes — without logging in. The other library isn't visible through it. Disable the link at any time.