On the Steam client, call ISteamUser::GetAuthTicketForWebApi to obtain a session ticket and send it to your game's EOS integration layer
Call EOS_Connect_Login with EOS_EExternalCredentialType set to EOS_ECT_STEAM_SESSION_TICKET and the hex-encoded ticket as the token
If the call returns EOS_InvalidUser, call EOS_Connect_CreateUser with the returned ContinuanceToken to create a new Product User ID bound to this Steam identity
To link an additional platform to an existing player, first authenticate the primary identity, then call EOS_Connect_Login with the new platform's credentials; on EOS_InvalidUser, call EOS_Connect_LinkAccount with the ContinuanceToken and the existing EOS_HConnect handle
Query entitlements using EOS_Ecom_QueryEntitlements against the PUID; the linked account allows entitlement access regardless of which platform the player logs in from
Known gotchas
Steam session tickets used for EOS_Connect_Login must be generated with GetAuthTicketForWebApi, not the older GetAuthSessionTicket; the identity string passed to GetAuthTicketForWebApi should match EOS's expected value — check Epic's current integration guide for the exact string
A PUID created from a Steam credential can have Epic Games Store entitlements linked to it only if an Epic Account is also linked via EOS Auth; EOS Connect alone does not grant access to EGS catalog items
ContinuanceTokens are short-lived; the linking or create-user call must be made within the token's validity window or the player must re-authenticate
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