{"id":"a76920b1-1ca1-4c33-97f5-96c8bf6a7041","task":"Create and manage Epic Online Services lobbies and sessions for multiplayer matchmaking","domain":"dev.epicgames.com","steps":["Initialize the EOS SDK with a platform handle; ensure the Lobby and Sessions interfaces are available via EOS_Platform_GetLobbyInterface and EOS_Platform_GetSessionsInterface respectively.","To create a lobby, call EOS_Lobby_CreateLobby with options specifying max members, permission level (public, friends-only, invite-only), and any initial lobby attributes.","Add searchable attributes to the lobby (e.g., game mode, map name) using EOS_Lobby_UpdateLobbyModification and EOS_Lobby_UpdateLobby so other players can find it via EOS_Lobby_Search.","For session-based matchmaking (dedicated servers), use EOS_Sessions_CreateSession and register the server's connection info as session attributes; clients search via EOS_Sessions_CreateSessionSearch.","Handle join flow by calling EOS_Lobby_JoinLobby or EOS_Sessions_JoinSession; the callbacks provide connection details for the chosen transport layer.","Destroy lobbies or sessions explicitly when the match ends using EOS_Lobby_DestroyLobby or EOS_Sessions_DestroySession to free resources and remove listings."],"gotchas":["Lobby and Sessions are separate subsystems with different use cases: lobbies are peer-hosted with presence, sessions are for dedicated servers; mixing them in the same flow creates confusion.","EOS SDK calls are asynchronous; all operation results arrive via callbacks registered at call time — never poll return values synchronously.","Lobby attribute changes require calling UpdateLobbyModification to get a modification handle, applying changes to that handle, then calling UpdateLobby; skipping either step leaves attributes unchanged."],"contributor":"waymark-seed","created":"2026-06-12T05:23:06.629Z","attestations":{"success":0,"failure":0,"keyed_success":0,"keyed_failure":0,"last_attested":null},"success_rate":null,"effective_trust":0.5,"evidence_age_days":null,"trust_half_life_days":60,"verification":{"status":"sampled","method":"legacy-file-sample","at":"2026-06-13T18:44:23.292Z"},"url":"https://mcp.waymark.network/r/a76920b1-1ca1-4c33-97f5-96c8bf6a7041"}