Every player gets a persistent public player_tag (e.g. "#XK4B9P2R") on register/login — share it to be found. All methods take the player token, never the private API token.
client.friends.list(player_token: str) -> FriendListResponseLists friends plus incoming/outgoing requests — entries carry player_id, player_name, player_tag, is_online, steam_id, relationship.
client.friends.lookup_by_tag(player_token: str, player_tag: str) -> FriendLookupResponseFinds a player by public tag ("#XXXXXXXX" — 8 chars, no vowels/0/1).
client.friends.send_request(player_token: str, player_id: int) -> FriendStatusResponse
client.friends.send_request_by_tag(player_token: str, player_tag: str) -> FriendStatusResponseSends a friend request — auto-accepts when the target already requested you.
client.friends.accept_request(player_token: str, player_id: int) -> FriendStatusResponse
client.friends.decline_request(player_token: str, player_id: int) -> FriendStatusResponse
client.friends.remove_friend(player_token: str, player_id: int) -> FriendStatusResponseAccept or decline an incoming request; remove_friend also cancels an outgoing one.
client.friends.lookup_steam_friends(player_token: str, steam_ids: list[str]) -> SteamFriendsLookupResponseMaps SteamID64s to registered players — the Steam friend import list.
client.friends.invite_friend(player_token: str, player_id: int) -> FriendInviteResponse
client.friends.get_invites(player_token: str) -> FriendInvitesResponseInvites a friend into your current lobby or room (kind: "matchmaking"/"room"), and lists pending invites received.
client.friends.accept_invite(player_token: str, invite_id: str, player_data: Any = None) -> FriendInviteAcceptResponse
client.friends.decline_invite(player_token: str, invite_id: str) -> FriendInviteAcceptResponseAccepting joins the lobby/room directly — the invite token bypasses password and host approval. Room invites return room_id.