diff --git a/apps/server/src/application/coordinators/disconnectCoordinator.ts b/apps/server/src/application/coordinators/disconnectCoordinator.ts
new file mode 100644
index 0000000..4d40e81
--- /dev/null
+++ b/apps/server/src/application/coordinators/disconnectCoordinator.ts
@@ -0,0 +1,28 @@
+/**
+ * disconnectCoordinator
+ * DISCONNECTイベントの調停を行い，ゲーム離脱処理とルーム離脱処理を順序実行する
+ */
+import { GameManager } from "@server/domains/game/GameManager";
+import { RoomManager } from "@server/domains/room/RoomManager";
+import { handleGameDisconnect } from "@server/network/handlers/GameHandler";
+import { handleRoomDisconnect } from "@server/network/handlers/RoomHandler";
+
+type DisconnectCoordinatorParams = {
+  io: Parameters<typeof handleGameDisconnect>[0];
+  socketId: string;
+  gameManager: GameManager;
+  roomManager: RoomManager;
+};
+
+/** 切断時にゲーム処理とルーム処理を調停し，一貫した離脱処理を実行する */
+export const disconnectCoordinator = ({
+  io,
+  socketId,
+  gameManager,
+  roomManager,
+}: DisconnectCoordinatorParams) => {
+  const roomId = roomManager.getRoomByPlayerId(socketId)?.roomId;
+
+  handleGameDisconnect(io, gameManager, roomId, socketId);
+  handleRoomDisconnect(io, socketId, roomManager);
+};
diff --git a/apps/server/src/application/coordinators/readyForGameCoordinator.ts b/apps/server/src/application/coordinators/readyForGameCoordinator.ts
new file mode 100644
index 0000000..407dc01
--- /dev/null
+++ b/apps/server/src/application/coordinators/readyForGameCoordinator.ts
@@ -0,0 +1,34 @@
+/**
+ * readyForGameCoordinator
+ * READY_FOR_GAMEイベントの調停を行い，所属ルーム解決と準備状態通知を橋渡しする
+ */
+import {
+  type GameOutputPort,
+  type ReadyForGamePort,
+  type ReadyForGameRoomPort,
+} from "@server/domains/game/application/ports/gameUseCasePorts";
+import { readyForGameUseCase } from "@server/domains/game/application/useCases/readyForGameUseCase";
+
+type ReadyForGameCoordinatorParams = {
+  socketId: string;
+  gameManager: ReadyForGamePort;
+  roomManager: ReadyForGameRoomPort;
+  output: Pick<GameOutputPort, "publishCurrentPlayersToSocket" | "publishGameStartToSocket">;
+};
+
+/** READY_FOR_GAME受信時に所属ルームを解決し，準備状態ユースケースを実行する */
+export const readyForGameCoordinator = ({
+  socketId,
+  gameManager,
+  roomManager,
+  output,
+}: ReadyForGameCoordinatorParams) => {
+  const room = roomManager.getRoomByPlayerId(socketId);
+
+  readyForGameUseCase({
+    socketId,
+    roomId: room?.roomId,
+    gameManager,
+    output,
+  });
+};
diff --git a/apps/server/src/application/coordinators/startGameCoordinator.ts b/apps/server/src/application/coordinators/startGameCoordinator.ts
index a4308fb..9ea5920 100644
--- a/apps/server/src/application/coordinators/startGameCoordinator.ts
+++ b/apps/server/src/application/coordinators/startGameCoordinator.ts
@@ -1,14 +1,20 @@
+/**
+ * startGameCoordinator
+ * START_GAMEイベントの調停を行い，ルーム状態更新とゲーム開始処理を橋渡しする
+ */
 import { roomConsts } from "@repo/shared";
 import { GameManager } from "@server/domains/game/GameManager";
-import { type GameOutputPort } from "@server/domains/game/application/ports/gameUseCasePorts";
+import {
+  type GameOutputPort,
+  type StartGameRoomPort,
+} from "@server/domains/game/application/ports/gameUseCasePorts";
 import { startGameUseCase } from "@server/domains/game/application/useCases/startGameUseCase";
-import { RoomManager } from "@server/domains/room/RoomManager";
 import { logEvent } from "@server/logging/logEvent";
 
 type StartGameCoordinatorParams = {
   ownerId: string;
   gameManager: GameManager;
-  roomManager: RoomManager;
+  roomManager: StartGameRoomPort;
   output: Pick<
     GameOutputPort,
     | "publishUpdatePlayerToRoom"
@@ -18,6 +24,7 @@
   >;
 };
 
+/** START_GAME受信時にルーム状態遷移を判定し，ゲーム開始ユースケースを実行する */
 export const startGameCoordinator = ({
   ownerId,
   gameManager,
diff --git a/apps/server/src/domains/game/GameManager.ts b/apps/server/src/domains/game/GameManager.ts
index 118abb7..c6f5a6f 100644
--- a/apps/server/src/domains/game/GameManager.ts
+++ b/apps/server/src/domains/game/GameManager.ts
@@ -1,3 +1,7 @@
+/**
+ * GameManager
+ * ゲームセッション集合の生成，更新，参照管理を統括する
+ */
 import { type TickData } from "./loop/GameLoop";
 import { Player } from "./entities/player/Player.js";
 import { GameRoomSession } from "./application/services/GameRoomSession";
@@ -5,6 +9,7 @@
 import { GamePlayerOperationService } from "./application/services/GamePlayerOperationService";
 
 // プレイヤー集合の生成・更新・参照管理クラス
+/** ゲームセッションのライフサイクルとプレイヤー操作を統括するマネージャ */
 export class GameManager {
   private sessions: Map<string, GameRoomSession>;
   private playerToRoom: Map<string, string>;
diff --git a/apps/server/src/domains/game/application/ports/gameUseCasePorts.ts b/apps/server/src/domains/game/application/ports/gameUseCasePorts.ts
index 659e636..c3f8e0f 100644
--- a/apps/server/src/domains/game/application/ports/gameUseCasePorts.ts
+++ b/apps/server/src/domains/game/application/ports/gameUseCasePorts.ts
@@ -1,6 +1,11 @@
+/**
+ * gameUseCasePorts
+ * ゲーム系ユースケースが利用する入力ポートと出力ポートの契約を定義する
+ */
 import type { TickData } from "../../loop/GameLoop";
 import type { gridMapTypes, playerTypes, roomTypes } from "@repo/shared";
 
+/** ゲーム開始ユースケースが利用するゲーム管理入力ポート */
 export interface StartGamePort {
   startRoomSession(
     roomId: string,
@@ -11,19 +16,35 @@
   getRoomStartTime(roomId: string): number | undefined;
 }
 
+/** ゲーム開始調停で利用するルーム管理入力ポート */
+export interface StartGameRoomPort {
+  getRoomByOwnerId(ownerId: string): roomTypes.Room | undefined;
+  markRoomPlaying(roomId: string): roomTypes.Room | undefined;
+  markRoomWaiting(roomId: string): roomTypes.Room | undefined;
+}
+
+/** 準備完了調停で利用するルーム解決入力ポート */
+export interface ReadyForGameRoomPort {
+  getRoomByPlayerId(playerId: string): roomTypes.Room | undefined;
+}
+
+/** 準備完了ユースケースが利用するゲーム状態参照入力ポート */
 export interface ReadyForGamePort {
   getRoomPlayers(roomId: string): playerTypes.PlayerData[];
   getRoomStartTime(roomId: string): number | undefined;
 }
 
+/** 移動入力ユースケースが利用するプレイヤー操作入力ポート */
 export interface MovePlayerPort {
   movePlayer(id: string, x: number, y: number): void;
 }
 
+/** 切断ユースケースが利用するプレイヤー削除入力ポート */
 export interface DisconnectPlayerPort {
   removePlayer(id: string): void;
 }
 
+/** ゲーム系ユースケースが利用する送信出力ポート */
 export interface GameOutputPort {
   publishPongToSocket(payload: { clientTime: number; serverTime: number }): void;
   publishUpdatePlayerToRoom(roomId: roomTypes.Room["roomId"], playerData: playerTypes.PlayerData): void;
diff --git a/apps/server/src/domains/game/application/services/GamePlayerOperationService.ts b/apps/server/src/domains/game/application/services/GamePlayerOperationService.ts
index 9c039c7..e6af25b 100644
--- a/apps/server/src/domains/game/application/services/GamePlayerOperationService.ts
+++ b/apps/server/src/domains/game/application/services/GamePlayerOperationService.ts
@@ -1,9 +1,14 @@
+/**
+ * GamePlayerOperationService
+ * ゲームセッション内のプレイヤー移動と離脱操作を管理する
+ */
 import { logEvent } from "@server/logging/logEvent";
 import { GameRoomSession } from "./GameRoomSession";
 
 type SessionStore = Map<string, GameRoomSession>;
 type PlayerRoomIndex = Map<string, string>;
 
+/** プレイヤー移動とセッション離脱処理を提供するサービス */
 export class GamePlayerOperationService {
   constructor(
     private sessions: SessionStore,
diff --git a/apps/server/src/domains/game/application/services/GameRoomSession.ts b/apps/server/src/domains/game/application/services/GameRoomSession.ts
index 4ac08b7..4e31055 100644
--- a/apps/server/src/domains/game/application/services/GameRoomSession.ts
+++ b/apps/server/src/domains/game/application/services/GameRoomSession.ts
@@ -1,3 +1,7 @@
+/**
+ * GameRoomSession
+ * 1ルーム分のゲーム進行状態とゲームループ実行を管理する
+ */
 import { logEvent } from "@server/logging/logEvent";
 import { GameLoop, type TickData } from "../../loop/GameLoop";
 import { Player } from "../../entities/player/Player.js";
@@ -8,6 +12,7 @@
   setPlayerPosition,
 } from "../../entities/player/playerMovement.js";
 
+/** ルーム単位のゲーム状態とループ進行を保持するセッションクラス */
 export class GameRoomSession {
   private players: Map<string, Player>;
   private mapStore: MapStore;
diff --git a/apps/server/src/domains/game/application/services/GameSessionLifecycleService.ts b/apps/server/src/domains/game/application/services/GameSessionLifecycleService.ts
index 333d259..0b22870 100644
--- a/apps/server/src/domains/game/application/services/GameSessionLifecycleService.ts
+++ b/apps/server/src/domains/game/application/services/GameSessionLifecycleService.ts
@@ -1,3 +1,7 @@
+/**
+ * GameSessionLifecycleService
+ * ゲームセッションの開始，参照，終了時クリーンアップを管理する
+ */
 import { config } from "@repo/shared";
 import { type TickData } from "../../loop/GameLoop";
 import { logEvent } from "@server/logging/logEvent";
@@ -6,6 +10,7 @@
 type SessionStore = Map<string, GameRoomSession>;
 type PlayerRoomIndex = Map<string, string>;
 
+/** ゲームセッションのライフサイクル操作を提供するサービス */
 export class GameSessionLifecycleService {
   constructor(
     private sessions: SessionStore,
diff --git a/apps/server/src/domains/game/application/useCases/disconnectUseCase.ts b/apps/server/src/domains/game/application/useCases/disconnectUseCase.ts
index 865ec74..bb6ca19 100644
--- a/apps/server/src/domains/game/application/useCases/disconnectUseCase.ts
+++ b/apps/server/src/domains/game/application/useCases/disconnectUseCase.ts
@@ -1,3 +1,7 @@
+/**
+ * disconnectUseCase
+ * 切断したプレイヤーをゲーム状態から除外し，必要に応じて通知を行う
+ */
 import type { DisconnectPlayerPort, GameOutputPort } from "../ports/gameUseCasePorts";
 import { logEvent } from "@server/logging/logEvent";
 
@@ -8,6 +12,7 @@
   output: Pick<GameOutputPort, "publishPlayerRemovedToRoom">;
 };
 
+/** プレイヤー切断時の状態更新と通知を実行する */
 export const disconnectUseCase = ({
   gameManager,
   roomId,
diff --git a/apps/server/src/domains/game/application/useCases/movePlayerUseCase.ts b/apps/server/src/domains/game/application/useCases/movePlayerUseCase.ts
index 9bcece1..400b1ae 100644
--- a/apps/server/src/domains/game/application/useCases/movePlayerUseCase.ts
+++ b/apps/server/src/domains/game/application/useCases/movePlayerUseCase.ts
@@ -1,3 +1,7 @@
+/**
+ * movePlayerUseCase
+ * プレイヤー移動入力を受け取り，ゲーム管理へ反映する
+ */
 import type { playerTypes } from "@repo/shared";
 import type { MovePlayerPort } from "../ports/gameUseCasePorts";
 
@@ -7,6 +11,7 @@
   move: playerTypes.MovePayload;
 };
 
+/** プレイヤー移動入力をゲーム管理へ委譲する */
 export const movePlayerUseCase = ({
   gameManager,
   playerId,
diff --git a/apps/server/src/domains/game/application/useCases/pingUseCase.ts b/apps/server/src/domains/game/application/useCases/pingUseCase.ts
index 42e8fbd..c357d66 100644
--- a/apps/server/src/domains/game/application/useCases/pingUseCase.ts
+++ b/apps/server/src/domains/game/application/useCases/pingUseCase.ts
@@ -1,3 +1,7 @@
+/**
+ * pingUseCase
+ * PING受信時に時刻情報付きPONGを返して遅延計測を支援する
+ */
 import type { GameOutputPort } from "../ports/gameUseCasePorts";
 
 type PingUseCaseParams = {
@@ -5,6 +9,7 @@
   output: Pick<GameOutputPort, "publishPongToSocket">;
 };
 
+/** クライアント時刻を受け取りサーバー時刻付きで応答する */
 export const pingUseCase = ({
   clientTime,
   output,
diff --git a/apps/server/src/domains/game/application/useCases/readyForGameUseCase.ts b/apps/server/src/domains/game/application/useCases/readyForGameUseCase.ts
index f8a72c0..f4696ad 100644
--- a/apps/server/src/domains/game/application/useCases/readyForGameUseCase.ts
+++ b/apps/server/src/domains/game/application/useCases/readyForGameUseCase.ts
@@ -1,3 +1,7 @@
+/**
+ * readyForGameUseCase
+ * READY_FOR_GAME受信時に現在プレイヤー状態と開始時刻を返却する
+ */
 import type { ReadyForGamePort } from "../ports/gameUseCasePorts";
 import type { GameOutputPort } from "../ports/gameUseCasePorts";
 import { logEvent } from "@server/logging/logEvent";
@@ -9,6 +13,7 @@
   output: Pick<GameOutputPort, "publishCurrentPlayersToSocket" | "publishGameStartToSocket">;
 };
 
+/** 準備完了通知に対してルーム状態を返却し，開始済みなら開始時刻も通知する */
 export const readyForGameUseCase = ({
   socketId,
   roomId,
diff --git a/apps/server/src/domains/game/application/useCases/startGameUseCase.ts b/apps/server/src/domains/game/application/useCases/startGameUseCase.ts
index 0b853c8..f4075f0 100644
--- a/apps/server/src/domains/game/application/useCases/startGameUseCase.ts
+++ b/apps/server/src/domains/game/application/useCases/startGameUseCase.ts
@@ -1,3 +1,7 @@
+/**
+ * startGameUseCase
+ * ルーム内プレイヤーでゲームセッションを開始し，進行イベントを通知する
+ */
 import type { GameOutputPort, StartGamePort } from "../ports/gameUseCasePorts";
 import { logEvent } from "@server/logging/logEvent";
 
@@ -15,6 +19,7 @@
   >;
 };
 
+/** ゲームセッション開始とティック通知，終了通知を実行する */
 export const startGameUseCase = ({
   roomId,
   playerIds,
diff --git a/apps/server/src/domains/game/entities/map/MapStore.ts b/apps/server/src/domains/game/entities/map/MapStore.ts
index 15b03f8..3880749 100644
--- a/apps/server/src/domains/game/entities/map/MapStore.ts
+++ b/apps/server/src/domains/game/entities/map/MapStore.ts
@@ -1,9 +1,13 @@
-// apps/server/src/domains/game/entities/map/MapStore.ts
+/**
+ * MapStore
+ * 塗り状態グリッドと差分更新キューを保持して提供する
+ */
 import type { gridMapTypes } from "@repo/shared";
 import { createInitialGridColors } from "./mapGrid.js";
 import { paintCellIfChanged } from "./mapPainting.js";
 import { drainPendingUpdates } from "./mapUpdates.js";
 
+/** ルーム内マップの塗り状態と更新差分を管理するストア */
 export class MapStore {
   // 全マスの現在の色（teamId）を保持
   private gridColors: number[];
diff --git a/apps/server/src/domains/game/entities/map/mapGrid.ts b/apps/server/src/domains/game/entities/map/mapGrid.ts
index c08cc21..f230acf 100644
--- a/apps/server/src/domains/game/entities/map/mapGrid.ts
+++ b/apps/server/src/domains/game/entities/map/mapGrid.ts
@@ -1,5 +1,10 @@
+/**
+ * mapGrid
+ * マップ配列の初期状態を生成する
+ */
 import { config } from "@repo/shared";
 
+/** マップ全セルを未塗り状態で初期化した配列を返す */
 export const createInitialGridColors = (): number[] => {
   const totalCells = config.GAME_CONFIG.GRID_COLS * config.GAME_CONFIG.GRID_ROWS;
   return new Array(totalCells).fill(-1);
diff --git a/apps/server/src/domains/game/entities/map/mapPainting.ts b/apps/server/src/domains/game/entities/map/mapPainting.ts
index c03eab1..8ffe9fb 100644
--- a/apps/server/src/domains/game/entities/map/mapPainting.ts
+++ b/apps/server/src/domains/game/entities/map/mapPainting.ts
@@ -1,3 +1,7 @@
+/**
+ * mapPainting
+ * マップセルの塗り更新と差分追加処理を提供する
+ */
 import type { gridMapTypes } from "@repo/shared";
 
 type PaintCellParams = {
@@ -7,6 +11,7 @@
   teamId: number;
 };
 
+/** マップセルの色が変わった場合のみ差分へ追加する */
 export const paintCellIfChanged = ({
   gridColors,
   pendingUpdates,
diff --git a/apps/server/src/domains/game/entities/map/mapUpdates.ts b/apps/server/src/domains/game/entities/map/mapUpdates.ts
index 091ed0b..9c51618 100644
--- a/apps/server/src/domains/game/entities/map/mapUpdates.ts
+++ b/apps/server/src/domains/game/entities/map/mapUpdates.ts
@@ -1,5 +1,10 @@
+/**
+ * mapUpdates
+ * マップ差分キューの取り出しとクリア処理を提供する
+ */
 import type { gridMapTypes } from "@repo/shared";
 
+/** 差分キューを配列として返却し，キューを空にする */
 export const drainPendingUpdates = (
   pendingUpdates: gridMapTypes.CellUpdate[]
 ): gridMapTypes.CellUpdate[] => {
diff --git a/apps/server/src/domains/game/entities/player/Player.ts b/apps/server/src/domains/game/entities/player/Player.ts
index 6e16617..68a033e 100644
--- a/apps/server/src/domains/game/entities/player/Player.ts
+++ b/apps/server/src/domains/game/entities/player/Player.ts
@@ -1,7 +1,12 @@
+/**
+ * Player
+ * サーバー側で保持するプレイヤー状態モデルを定義する
+ */
 import type { playerTypes } from "@repo/shared";
 import { config } from "@repo/shared";
 
 // サーバー側保持プレイヤー状態モデル
+/** サーバー側プレイヤー座標と所属チームを保持するエンティティ */
 export class Player implements playerTypes.PlayerData {
   public id: string;
   public x: number = 0;
diff --git a/apps/server/src/domains/game/entities/player/playerMovement.ts b/apps/server/src/domains/game/entities/player/playerMovement.ts
index b7cd590..a53a88b 100644
--- a/apps/server/src/domains/game/entities/player/playerMovement.ts
+++ b/apps/server/src/domains/game/entities/player/playerMovement.ts
@@ -1,9 +1,15 @@
+/**
+ * playerMovement
+ * プレイヤー座標の検証と更新処理を提供する
+ */
 import { Player } from "./Player.js";
 
+/** 座標値が有限数かを判定する */
 export const isValidPosition = (x: number, y: number): boolean => {
   return Number.isFinite(x) && Number.isFinite(y);
 };
 
+/** プレイヤー座標を新しい値へ更新する */
 export const setPlayerPosition = (
   player: Player,
   x: number,
diff --git a/apps/server/src/domains/game/entities/player/playerPosition.ts b/apps/server/src/domains/game/entities/player/playerPosition.ts
index f0c825a..0a2112c 100644
--- a/apps/server/src/domains/game/entities/player/playerPosition.ts
+++ b/apps/server/src/domains/game/entities/player/playerPosition.ts
@@ -1,6 +1,11 @@
+/**
+ * playerPosition
+ * プレイヤー座標からマップ上のセル位置を解決する
+ */
 import { gridMapLogic } from "@repo/shared";
 import { Player } from "./Player.js";
 
+/** プレイヤー座標に対応するグリッドインデックスを返す */
 export const getPlayerGridIndex = (player: Player): number | null => {
   return gridMapLogic.getGridIndexFromPosition(player.x, player.y);
 };
diff --git a/apps/server/src/domains/game/entities/player/playerSpawn.ts b/apps/server/src/domains/game/entities/player/playerSpawn.ts
index 064a690..c09e4ae 100644
--- a/apps/server/src/domains/game/entities/player/playerSpawn.ts
+++ b/apps/server/src/domains/game/entities/player/playerSpawn.ts
@@ -1,6 +1,11 @@
+/**
+ * playerSpawn
+ * プレイヤー初期生成時のスポーン座標設定を提供する
+ */
 import { config } from "@repo/shared";
 import { Player } from "./Player.js";
 
+/** プレイヤーを生成し，初期スポーン座標を設定して返す */
 export const createSpawnedPlayer = (id: string): Player => {
   const player = new Player(id);
   player.x = config.GAME_CONFIG.GRID_COLS / 2;
diff --git a/apps/server/src/domains/game/loop/GameLoop.ts b/apps/server/src/domains/game/loop/GameLoop.ts
index de3617c..c5a9f9e 100644
--- a/apps/server/src/domains/game/loop/GameLoop.ts
+++ b/apps/server/src/domains/game/loop/GameLoop.ts
@@ -1,3 +1,7 @@
+/**
+ * GameLoop
+ * ルーム単位の定周期更新を実行し，プレイヤー状態とマップ差分を集約する
+ */
 import { Player } from "../entities/player/Player.js";
 import { MapStore } from "../entities/map/MapStore";
 import { getPlayerGridIndex } from "../entities/player/playerPosition.js";
@@ -6,6 +10,7 @@
 import { logEvent } from "@server/logging/logEvent";
 
 // コールバックで渡すデータの型定義
+/** 1ティック分のプレイヤー情報とマップ差分を表すデータ */
 export interface TickData {
   players: {
     id: string;
@@ -16,6 +21,7 @@
   cellUpdates: gridMapTypes.CellUpdate[];
 }
 
+/** ルーム内ゲーム進行を定周期で実行するループ管理クラス */
 export class GameLoop {
   private loopId: NodeJS.Timeout | null = null;
   private startTime: number = 0;
diff --git a/apps/server/src/index.ts b/apps/server/src/index.ts
index 77f2750..f7138f6 100644
--- a/apps/server/src/index.ts
+++ b/apps/server/src/index.ts
@@ -1,3 +1,7 @@
+/**
+ * index
+ * サーバー起動時にHTTPサーバー生成とブート処理を実行する
+ */
 import { createHttpServer } from "./network/bootstrap/createHttpServer";
 import { boot } from "./network/bootstrap/boot";
 import { config } from "@repo/shared";
diff --git a/apps/server/src/logging/logEvent.ts b/apps/server/src/logging/logEvent.ts
index 626324c..c521ab8 100644
--- a/apps/server/src/logging/logEvent.ts
+++ b/apps/server/src/logging/logEvent.ts
@@ -1,3 +1,7 @@
+/**
+ * logEvent
+ * 共通ログ出力で利用するイベントログ関数を提供する
+ */
 type LogEventPayload = {
   event: string;
   result: string;
@@ -6,6 +10,7 @@
   [key: string]: unknown;
 };
 
+/** スコープ名とイベント情報を標準出力へ記録する */
 export const logEvent = (scope: string, payload: LogEventPayload) => {
   console.log(`[${scope}]`, payload);
 };
diff --git a/apps/server/src/network/handlers/game/registerGameHandlers.ts b/apps/server/src/network/handlers/game/registerGameHandlers.ts
index bdd4cc0..a50c94d 100644
--- a/apps/server/src/network/handlers/game/registerGameHandlers.ts
+++ b/apps/server/src/network/handlers/game/registerGameHandlers.ts
@@ -7,13 +7,13 @@
 import { RoomManager } from "@server/domains/room/RoomManager";
 import { protocol } from "@repo/shared";
 import { pingUseCase } from "@server/domains/game/application/useCases/pingUseCase";
-import { readyForGameUseCase } from "@server/domains/game/application/useCases/readyForGameUseCase";
 import { movePlayerUseCase } from "@server/domains/game/application/useCases/movePlayerUseCase";
 import { createCommonHandlerContext } from "@server/network/handlers/CommonHandler";
 import { createGameOutputAdapter } from "./createGameOutputAdapter";
 import { logEvent } from "@server/logging/logEvent";
 import { isMovePayload, isPingPayload } from "@server/network/validation/socketPayloadValidators";
 import { startGameCoordinator } from "@server/application/coordinators/startGameCoordinator";
+import { readyForGameCoordinator } from "@server/application/coordinators/readyForGameCoordinator";
 
 /** ゲームイベントの購読とユースケース呼び出しを設定する */
 export const registerGameHandlers = (
@@ -54,12 +54,10 @@
 
   // 参加者の準備完了通知を受けて現在状態を返す
   socket.on(protocol.SocketEvents.READY_FOR_GAME, () => {
-    const roomId = Array.from(socket.rooms).find((room) => room !== socket.id);
-
-    readyForGameUseCase({
+    readyForGameCoordinator({
       socketId: socket.id,
-      roomId,
       gameManager,
+      roomManager,
       output: gameOutputAdapter,
     });
   });
diff --git a/apps/server/src/network/handlers/registerConnectionHandlers.ts b/apps/server/src/network/handlers/registerConnectionHandlers.ts
index fa871f9..d5e6917 100644
--- a/apps/server/src/network/handlers/registerConnectionHandlers.ts
+++ b/apps/server/src/network/handlers/registerConnectionHandlers.ts
@@ -6,9 +6,10 @@
 import { GameManager } from "@server/domains/game/GameManager";
 import { RoomManager } from "@server/domains/room/RoomManager";
 import { protocol } from "@repo/shared";
-import { registerRoomHandlers, handleRoomDisconnect } from "./RoomHandler";
-import { registerGameHandlers, handleGameDisconnect } from "./GameHandler";
+import { registerRoomHandlers } from "./RoomHandler";
+import { registerGameHandlers } from "./GameHandler";
 import { logEvent } from "@server/logging/logEvent";
+import { disconnectCoordinator } from "@server/application/coordinators/disconnectCoordinator";
 
 type RegisterConnectionHandlersParams = {
   io: Server;
@@ -41,10 +42,12 @@
         socketId: socket.id,
       });
 
-      const roomId = roomManager.getRoomByPlayerId(socket.id)?.roomId;
-
-      handleGameDisconnect(io, gameManager, roomId, socket.id);
-      handleRoomDisconnect(io, socket, roomManager);
+      disconnectCoordinator({
+        io,
+        socketId: socket.id,
+        gameManager,
+        roomManager,
+      });
     });
   });
 };
diff --git a/apps/server/src/network/handlers/room/handleRoomDisconnect.ts b/apps/server/src/network/handlers/room/handleRoomDisconnect.ts
index 998b0f9..7c92990 100644
--- a/apps/server/src/network/handlers/room/handleRoomDisconnect.ts
+++ b/apps/server/src/network/handlers/room/handleRoomDisconnect.ts
@@ -2,7 +2,7 @@
  * handleRoomDisconnect
  * ルーム切断ユースケースを呼び出してルーム状態更新を配信する
  */
-import { Server, Socket } from "socket.io";
+import { Server } from "socket.io";
 import { RoomManager } from "@server/domains/room/RoomManager";
 import { roomDisconnectUseCase } from "@server/domains/room/application/useCases/roomDisconnectUseCase";
 import { createRoomDisconnectOutputAdapter } from "./createRoomOutputAdapter";
@@ -10,14 +10,14 @@
 /** 切断ソケットのルーム離脱処理を実行して更新通知する */
 export const handleRoomDisconnect = (
   io: Server,
-  socket: Socket,
+  socketId: string,
   roomManager: RoomManager
 ) => {
   const roomDisconnectOutputAdapter = createRoomDisconnectOutputAdapter(io);
 
   roomDisconnectUseCase({
     roomManager,
-    socketId: socket.id,
+    socketId,
     output: roomDisconnectOutputAdapter,
   });
 };