diff --git a/cocoscreator_projects/YouleNexus/assets/framework/platform/commands.ts b/cocoscreator_projects/YouleNexus/assets/framework/platform/commands.ts
new file mode 100644
index 0000000..fafcdcd
--- /dev/null
+++ b/cocoscreator_projects/YouleNexus/assets/framework/platform/commands.ts
@@ -0,0 +1,96 @@
+import type { RuntimeConfig } from '../config/runtime-config.ts';
+import type { OutboundEnvelope } from '../core/types/envelope.ts';
+import {
+  buildExitRoomRequest,
+  buildJoinRoomRequest,
+  buildPrepareRequest,
+  type JoinRoomEnvironment,
+  type RoomIdentity,
+} from '../protocol/contracts/index.ts';
+import { PlatformStore } from './stores/platform-store.ts';
+import type { InsideRoomState, PlatformState } from './stores/platform-types.ts';
+
+/** The complete-envelope send capability used by platform command adapters. */
+export interface OutboundEnvelopeSendPort {
+  send(envelope: OutboundEnvelope): void;
+}
+
+export interface PlatformCommandsOptions {
+  readonly runtimeConfig: RuntimeConfig;
+  readonly store: PlatformStore;
+  readonly send: OutboundEnvelopeSendPort;
+}
+
+export interface JoinRoomCommand extends JoinRoomEnvironment {
+  readonly roomcode: string;
+}
+
+export class UnsupportedGameHostCommandError extends Error {
+  constructor(message: string) {
+    super(message);
+    this.name = 'UnsupportedGameHostCommandError';
+  }
+}
+
+/** Builds platform-owned room requests exclusively through the first-slice contracts. */
+export class PlatformCommands {
+  constructor(private readonly options: PlatformCommandsOptions) {}
+
+  prepare(): void {
+    const state = this.options.store.getState();
+    this.options.send.send(buildPrepareRequest(
+      this.options.runtimeConfig,
+      this.roomIdentity(state, this.requireInsideRoom(state)),
+    ));
+  }
+
+  exitRoom(): void {
+    const state = this.options.store.getState();
+    const room = this.requireInsideRoom(state);
+    if (room.stage !== 0) {
+      throw new UnsupportedGameHostCommandError('room.exit requires stage=0');
+    }
+    this.options.send.send(buildExitRoomRequest(
+      this.options.runtimeConfig,
+      this.roomIdentity(state, room),
+    ));
+  }
+
+  joinRoom(command: JoinRoomCommand): void {
+    const state = this.options.store.getState();
+    if (state.room.kind !== 'outside') {
+      throw new UnsupportedGameHostCommandError('room.join requires player to be outside a room');
+    }
+    const playerid = this.requireAuthenticatedPlayerId(state);
+    this.options.send.send(buildJoinRoomRequest(
+      this.options.runtimeConfig,
+      { playerid, roomcode: command.roomcode },
+      command,
+    ));
+  }
+
+  private requireInsideRoom(state: PlatformState): InsideRoomState {
+    if (state.room.kind !== 'inside') {
+      throw new UnsupportedGameHostCommandError('room command requires player to be inside a room');
+    }
+    return state.room;
+  }
+
+  private requireAuthenticatedPlayerId(state: PlatformState): number {
+    const playerid = state.players.selfPlayerId;
+    if (playerid === null) {
+      throw new UnsupportedGameHostCommandError('room command requires an authenticated player');
+    }
+    if (state.players.entities[playerid] === undefined) {
+      throw new Error('players.entities: missing authenticated player');
+    }
+    return playerid;
+  }
+
+  private roomIdentity(state: PlatformState, room: InsideRoomState): RoomIdentity {
+    return {
+      playerid: this.requireAuthenticatedPlayerId(state),
+      roomcode: room.roomcode,
+    };
+  }
+}
diff --git a/cocoscreator_projects/YouleNexus/assets/framework/platform/game-host-adapter.ts b/cocoscreator_projects/YouleNexus/assets/framework/platform/game-host-adapter.ts
new file mode 100644
index 0000000..63c05be
--- /dev/null
+++ b/cocoscreator_projects/YouleNexus/assets/framework/platform/game-host-adapter.ts
@@ -0,0 +1,289 @@
+import { APP } from '../core/constants.ts';
+import type { OutboundEnvelope } from '../core/types/envelope.ts';
+import type {
+  GameEntry,
+  GameHost,
+  GameHostCommand,
+  GameSeatMapper,
+  PlatformGameSnapshot,
+} from '../sdk/contracts/index.ts';
+import {
+  PlatformCommands,
+  UnsupportedGameHostCommandError,
+  type OutboundEnvelopeSendPort,
+} from './commands.ts';
+import { PlatformStore } from './stores/platform-store.ts';
+import { selectGameSnapshot } from './stores/selectors.ts';
+import type { PlatformState } from './stores/platform-types.ts';
+
+const RESERVED_ROUTES = new Set(['platform', 'agent', 'room']);
+
+export class GameSessionDisposedError extends Error {
+  constructor() {
+    super('GameHost session lease is disposed');
+    this.name = 'GameSessionDisposedError';
+  }
+}
+
+export interface CreateGameHostAdapterOptions {
+  readonly gameEntry: GameEntry;
+  readonly store: PlatformStore;
+  readonly commands: PlatformCommands;
+  readonly send: OutboundEnvelopeSendPort;
+}
+
+/** Structurally matches RuntimeSession's per-open GameHostLeasePort. */
+export interface GameHostLease {
+  readonly host: GameHost;
+  invalidate(): void;
+}
+
+interface SubscriptionRecord {
+  active: boolean;
+  unsubscribeStore: (() => void) | null;
+}
+
+type SubscriptionReleaseResult =
+  | { readonly threw: false }
+  | { readonly threw: true; readonly error: unknown };
+
+class GameHostInvalidationError extends Error {
+  readonly errors: readonly unknown[];
+
+  constructor(errors: readonly unknown[]) {
+    super('GameHost subscription cleanup failed');
+    this.name = 'GameHostInvalidationError';
+    this.errors = Object.freeze([...errors]);
+  }
+}
+
+class SessionBoundGameHost {
+  readonly host: GameHost;
+
+  private store: PlatformStore | null;
+  private commands: PlatformCommands | null;
+  private sendPort: OutboundEnvelopeSendPort | null;
+  private route: string | null;
+  private readonly subscriptions = new Set<SubscriptionRecord>();
+  private disposed = false;
+
+  constructor(options: CreateGameHostAdapterOptions) {
+    const route = requireGameRoute(options.gameEntry.route);
+    const state = options.store.getState();
+    if (state.room.kind !== 'inside') {
+      throw new Error('GameHost requires player to be inside a room');
+    }
+    const seatCount = options.gameEntry.resolveSeatCount(state.room.roomtype);
+    requireSeatCount(seatCount, state.room.seatPlayerIds.length);
+    const selfSeat = requireSeat(state.room.selfSeat, seatCount, 'self seat');
+
+    this.store = options.store;
+    this.commands = options.commands;
+    this.sendPort = options.send;
+    this.route = route;
+
+    const seat: GameSeatMapper = Object.freeze({
+      toView: (serverSeat: number): number => {
+        this.requireActive();
+        const validated = requireSeat(serverSeat, seatCount, 'server seat');
+        return (validated - selfSeat + seatCount) % seatCount;
+      },
+      toServer: (viewSeat: number): number => {
+        this.requireActive();
+        const validated = requireSeat(viewSeat, seatCount, 'view seat');
+        return (validated + selfSeat) % seatCount;
+      },
+    });
+
+    this.host = Object.freeze({
+      seat,
+      getSnapshot: (): PlatformGameSnapshot => this.getSnapshot(),
+      subscribe: (listener: (snapshot: PlatformGameSnapshot) => void): (() => void) => (
+        this.subscribe(listener)
+      ),
+      sendGameMessage: (rpc: string, data: unknown): void => this.sendGameMessage(rpc, data),
+      execute: (command: GameHostCommand): void => this.execute(command),
+    });
+  }
+
+  invalidate(): void {
+    if (this.disposed) return;
+    this.disposed = true;
+
+    const subscriptions = [...this.subscriptions];
+    this.subscriptions.clear();
+    this.store = null;
+    this.commands = null;
+    this.sendPort = null;
+    this.route = null;
+
+    const errors: unknown[] = [];
+    for (const record of subscriptions) {
+      const result = this.releaseSubscription(record);
+      if (result.threw) errors.push(result.error);
+    }
+    if (errors.length === 1) throw errors[0];
+    if (errors.length > 1) throw new GameHostInvalidationError(errors);
+  }
+
+  private getSnapshot(): PlatformGameSnapshot {
+    return selectGameSnapshot(this.requireStore().getState());
+  }
+
+  private subscribe(listener: (snapshot: PlatformGameSnapshot) => void): () => void {
+    this.requireActive();
+    if (typeof listener !== 'function') {
+      throw new TypeError('GameHost subscribe listener must be a function');
+    }
+    const store = this.requireStore();
+    let current = selectGameSnapshot(store.getState());
+    const record: SubscriptionRecord = { active: true, unsubscribeStore: null };
+    const bridge = (state: PlatformState): void => {
+      if (this.disposed || !record.active || state.room.kind !== 'inside') return;
+      const next = selectGameSnapshot(state);
+      if (samePublicSnapshot(current, next)) return;
+      current = next;
+      listener(next);
+    };
+    record.unsubscribeStore = store.subscribe(bridge);
+    this.subscriptions.add(record);
+
+    try {
+      listener(current);
+    } catch (error) {
+      this.releaseSubscription(record);
+      throw error;
+    }
+
+    return (): void => {
+      try {
+        this.releaseSubscription(record);
+      } catch {
+        // The public unsubscribe contract remains non-throwing, including after invalidation.
+      }
+    };
+  }
+
+  private sendGameMessage(rpc: string, data: unknown): void {
+    this.requireActive();
+    if (typeof rpc !== 'string' || rpc.trim() === '') {
+      throw new TypeError('GameHost rpc must be a non-empty string');
+    }
+    const sendPort = this.sendPort;
+    const route = this.route;
+    if (sendPort === null || route === null) throw new GameSessionDisposedError();
+    const envelope: OutboundEnvelope = { app: APP, route, rpc, data };
+    sendPort.send(envelope);
+  }
+
+  private execute(command: GameHostCommand): void {
+    this.requireActive();
+    const commands = this.commands;
+    if (commands === null) throw new GameSessionDisposedError();
+    if (command !== null && typeof command === 'object') {
+      if (command.type === 'room.prepare') {
+        commands.prepare();
+        return;
+      }
+      if (command.type === 'room.exit') {
+        commands.exitRoom();
+        return;
+      }
+    }
+    throw new UnsupportedGameHostCommandError('unsupported GameHost command');
+  }
+
+  private requireStore(): PlatformStore {
+    this.requireActive();
+    const store = this.store;
+    if (store === null) throw new GameSessionDisposedError();
+    return store;
+  }
+
+  private requireActive(): void {
+    if (this.disposed) throw new GameSessionDisposedError();
+  }
+
+  private releaseSubscription(record: SubscriptionRecord): SubscriptionReleaseResult {
+    if (!record.active) return { threw: false };
+    record.active = false;
+    this.subscriptions.delete(record);
+    const unsubscribe = record.unsubscribeStore;
+    record.unsubscribeStore = null;
+    if (unsubscribe === null) return { threw: false };
+    try {
+      unsubscribe();
+      return { threw: false };
+    } catch (error) {
+      return { threw: true, error };
+    }
+  }
+}
+
+export function createGameHostAdapter(options: CreateGameHostAdapterOptions): GameHostLease {
+  const session = new SessionBoundGameHost(options);
+  return Object.freeze({
+    host: session.host,
+    invalidate: (): void => { session.invalidate(); },
+  });
+}
+
+function requireGameRoute(route: unknown): string {
+  if (typeof route !== 'string' || route.trim() === '') {
+    throw new TypeError('GameEntry route must be a non-empty string');
+  }
+  if (RESERVED_ROUTES.has(route)) {
+    throw new Error(`GameEntry reserved route: ${route}`);
+  }
+  return route;
+}
+
+function requireSeatCount(seatCount: unknown, roomSeatCount: number): asserts seatCount is number {
+  if (!Number.isInteger(seatCount) || (seatCount as number) <= 0) {
+    throw new RangeError(`GameEntry seat count must be a positive integer: ${String(seatCount)}`);
+  }
+  if (seatCount !== roomSeatCount) {
+    throw new RangeError(
+      `GameEntry seat count ${seatCount} does not match room seat count ${roomSeatCount}`,
+    );
+  }
+}
+
+function requireSeat(value: unknown, seatCount: number, label: string): number {
+  if (!Number.isInteger(value)) {
+    throw new TypeError(`${label}: expected integer seat, received ${String(value)}`);
+  }
+  const seat = value as number;
+  if (seat < 0 || seat >= seatCount) {
+    throw new RangeError(`${label}: expected seat range 0..${seatCount - 1}, received ${seat}`);
+  }
+  return seat;
+}
+
+function samePublicSnapshot(first: PlatformGameSnapshot, second: PlatformGameSnapshot): boolean {
+  if (first === second) return true;
+  if (
+    first.connection.phase !== second.connection.phase
+    || first.self.playerId !== second.self.playerId
+    || first.self.seat !== second.self.seat
+    || first.room.roomcode !== second.room.roomcode
+    || first.room.roomtype !== second.room.roomtype
+    || first.room.stage !== second.room.stage
+    || first.room.needprepare !== second.room.needprepare
+    || first.room.infinite !== second.room.infinite
+    || first.seats.length !== second.seats.length
+  ) return false;
+  for (let index = 0; index < first.seats.length; index++) {
+    const left = first.seats[index]!;
+    const right = second.seats[index]!;
+    if (
+      left.seat !== right.seat
+      || left.playerId !== right.playerId
+      || left.nickname !== right.nickname
+      || left.avatar !== right.avatar
+      || left.online !== right.online
+      || left.ready !== right.ready
+    ) return false;
+  }
+  return true;
+}
diff --git a/cocoscreator_projects/framework-tests/platform/commands.test.ts b/cocoscreator_projects/framework-tests/platform/commands.test.ts
new file mode 100644
index 0000000..d010656
--- /dev/null
+++ b/cocoscreator_projects/framework-tests/platform/commands.test.ts
@@ -0,0 +1,154 @@
+import assert from 'node:assert/strict';
+import { readFileSync } from 'node:fs';
+import { test } from 'node:test';
+import type { RuntimeConfig } from '../../YouleNexus/assets/framework/config/runtime-config.ts';
+import type { OutboundEnvelope } from '../../YouleNexus/assets/framework/core/types/envelope.ts';
+import { PlatformCommands } from '../../YouleNexus/assets/framework/platform/commands.ts';
+import { PlatformStore } from '../../YouleNexus/assets/framework/platform/stores/platform-store.ts';
+import {
+  parseLoginResponse,
+} from '../../YouleNexus/assets/framework/protocol/contracts/index.ts';
+
+const RUNTIME_CONFIG: RuntimeConfig = Object.freeze({
+  mode: 'release',
+  isDebugger: false,
+  identity: Object.freeze({
+    agentid: 'agent-from-config',
+    channelid: 'channel-from-config',
+    gameid: 'game-from-config',
+    marketid: 'market-from-config',
+    version: 41,
+  }),
+  servers: Object.freeze(['ws://fixture']),
+  source: 'remote',
+  gameserver: 'https://fixture/config',
+  rawConfig: Object.freeze({ data: Object.freeze({ urlserver: 'fixture' }) }),
+});
+
+function fixture(name: string): { data: Record<string, unknown> } {
+  return JSON.parse(readFileSync(new URL(`../fixtures/contracts/${name}`, import.meta.url), 'utf8'));
+}
+
+function makeStore(location: 'outside' | 'inside', stage = 0): PlatformStore {
+  const store = new PlatformStore();
+  const source = fixture(location === 'inside' ? 'player-login-room.json' : 'player-login-success.json');
+  if (location === 'inside') source.data.isbattle = stage;
+  store.applyLoginSuccess(parseLoginResponse(source.data));
+  return store;
+}
+
+function makeCommands(store: PlatformStore): {
+  readonly commands: PlatformCommands;
+  readonly sent: OutboundEnvelope[];
+} {
+  const sent: OutboundEnvelope[] = [];
+  return {
+    commands: new PlatformCommands({
+      runtimeConfig: RUNTIME_CONFIG,
+      store,
+      send: { send: (envelope) => { sent.push(envelope); } },
+    }),
+    sent,
+  };
+}
+
+test('prepare and exitRoom use the first-slice builders with authoritative config and room state', () => {
+  const { commands, sent } = makeCommands(makeStore('inside', 0));
+
+  commands.prepare();
+  commands.exitRoom();
+
+  assert.deepEqual(sent, [
+    {
+      app: 'youle',
+      route: 'room',
+      rpc: 'player_prepare',
+      data: {
+        agentid: 'agent-from-config',
+        playerid: 430511,
+        gameid: 'game-from-config',
+        roomcode: '100001',
+      },
+    },
+    {
+      app: 'youle',
+      route: 'room',
+      rpc: 'self_exit_room',
+      data: {
+        agentid: 'agent-from-config',
+        playerid: 430511,
+        gameid: 'game-from-config',
+        roomcode: '100001',
+      },
+    },
+  ]);
+  assert.equal(commands.prepare.length, 0);
+  assert.equal(commands.exitRoom.length, 0);
+});
+
+test('joinRoom uses authenticated Store identity and requires every non-optional environment field', () => {
+  const { commands, sent } = makeCommands(makeStore('outside'));
+  const location = { latitude: 28.7, longitude: 115.8 };
+
+  commands.joinRoom({
+    roomcode: '654321',
+    location,
+    ip: '203.0.113.7',
+    vipMatch: 1,
+    match_id: 'match-9',
+  });
+
+  assert.deepEqual(sent, [{
+    app: 'youle',
+    route: 'agent',
+    rpc: 'self_join_room',
+    data: {
+      agentid: 'agent-from-config',
+      playerid: 430511,
+      gameid: 'game-from-config',
+      roomcode: '654321',
+      location,
+      ip: '203.0.113.7',
+      vipMatch: 1,
+      match_id: 'match-9',
+    },
+  }]);
+  assert.equal((sent[0]!.data as { location: unknown }).location, location);
+  assert.equal(commands.joinRoom.length, 1);
+
+  assert.throws(
+    () => commands.joinRoom({ roomcode: '654321', ip: '203.0.113.7' } as never),
+    /location/i,
+  );
+  assert.throws(
+    () => commands.joinRoom({ roomcode: '654321', location } as never),
+    /ip/i,
+  );
+  assert.equal(sent.length, 1);
+});
+
+test('command preconditions reject missing authentication, wrong room location, and battle exit without sending', () => {
+  const unauthenticated = makeCommands(new PlatformStore());
+  assert.throws(
+    () => unauthenticated.commands.joinRoom({ roomcode: '654321', location: null, ip: '' }),
+    /authenticated|player/i,
+  );
+
+  const outside = makeCommands(makeStore('outside'));
+  assert.throws(() => outside.commands.prepare(), /inside.*room|room.*inside/i);
+  assert.throws(() => outside.commands.exitRoom(), /inside.*room|room.*inside/i);
+
+  const inside = makeCommands(makeStore('inside', 0));
+  assert.throws(
+    () => inside.commands.joinRoom({ roomcode: '654321', location: null, ip: '' }),
+    /outside.*room|already.*room/i,
+  );
+
+  const battle = makeCommands(makeStore('inside', 1));
+  assert.throws(() => battle.commands.exitRoom(), /room\.exit.*stage=0/i);
+
+  assert.equal(unauthenticated.sent.length, 0);
+  assert.equal(outside.sent.length, 0);
+  assert.equal(inside.sent.length, 0);
+  assert.equal(battle.sent.length, 0);
+});
diff --git a/cocoscreator_projects/framework-tests/platform/game-host-adapter.test.ts b/cocoscreator_projects/framework-tests/platform/game-host-adapter.test.ts
new file mode 100644
index 0000000..b2280fa
--- /dev/null
+++ b/cocoscreator_projects/framework-tests/platform/game-host-adapter.test.ts
@@ -0,0 +1,363 @@
+import assert from 'node:assert/strict';
+import { readFileSync } from 'node:fs';
+import { test } from 'node:test';
+import type { RuntimeConfig } from '../../YouleNexus/assets/framework/config/runtime-config.ts';
+import type { OutboundEnvelope } from '../../YouleNexus/assets/framework/core/types/envelope.ts';
+import {
+  createGameHostAdapter,
+  GameSessionDisposedError,
+} from '../../YouleNexus/assets/framework/platform/game-host-adapter.ts';
+import { PlatformCommands } from '../../YouleNexus/assets/framework/platform/commands.ts';
+import { PlatformStore } from '../../YouleNexus/assets/framework/platform/stores/platform-store.ts';
+import type {
+  PlatformState,
+} from '../../YouleNexus/assets/framework/platform/stores/platform-types.ts';
+import {
+  parseLoginResponse,
+  parseOtherJoinRoomPayload,
+  parsePlayerPreparePayload,
+} from '../../YouleNexus/assets/framework/protocol/contracts/index.ts';
+import type {
+  GameEntry,
+  GameHostCommand,
+} from '../../YouleNexus/assets/framework/sdk/contracts/index.ts';
+
+const RUNTIME_CONFIG: RuntimeConfig = Object.freeze({
+  mode: 'release',
+  isDebugger: false,
+  identity: Object.freeze({
+    agentid: 17,
+    channelid: 18,
+    gameid: 'game-41',
+    marketid: 19,
+    version: 41,
+  }),
+  servers: Object.freeze(['ws://fixture']),
+  source: 'remote',
+  gameserver: 'https://fixture/config',
+  rawConfig: Object.freeze({ data: Object.freeze({ urlserver: 'fixture' }) }),
+});
+
+function fixture(name: string): { data: Record<string, unknown> } {
+  return JSON.parse(readFileSync(new URL(`../fixtures/contracts/${name}`, import.meta.url), 'utf8'));
+}
+
+function roomStore(seatCount = 4, selfSeat = 1, stage = 0): PlatformStore {
+  const source = fixture('player-login-room.json');
+  const self = (source.data.players as Array<Record<string, unknown> | null>)[1]!;
+  const players = Array.from({ length: seatCount }, () => null) as Array<Record<string, unknown> | null>;
+  players[selfSeat] = { ...self };
+  source.data.players = players;
+  source.data.seat = selfSeat;
+  source.data.roomtype = [seatCount, { nested: [1, 2] }];
+  source.data.isbattle = stage;
+  const store = new PlatformStore();
+  store.applyLoginSuccess(parseLoginResponse(source.data));
+  return store;
+}
+
+function entry(route = 'fixture-route'): GameEntry {
+  return {
+    key: 'fixture',
+    gameId: 'game-41',
+    route,
+    resolveSeatCount: (roomtype) => roomtype[0] as number,
+    createModule: () => ({
+      attach() {}, handlePlatformEvent() {}, handleGameMessage() {}, restore() {}, dispose() {},
+    }),
+  };
+}
+
+function makeLease(options: {
+  readonly store?: PlatformStore;
+  readonly gameEntry?: GameEntry;
+} = {}) {
+  const store = options.store ?? roomStore();
+  const sent: OutboundEnvelope[] = [];
+  const send = { send: (envelope: OutboundEnvelope) => { sent.push(envelope); } };
+  const commands = new PlatformCommands({ runtimeConfig: RUNTIME_CONFIG, store, send });
+  const lease = createGameHostAdapter({
+    gameEntry: options.gameEntry ?? entry(),
+    store,
+    commands,
+    send,
+  });
+  return { ...lease, store, sent };
+}
+
+test('sendGameMessage binds app and GameEntry route, rejects empty rpc, and preserves data identity', () => {
+  const { host, sent } = makeLease();
+  const data = { card: 7 };
+
+  host.sendGameMessage('play-card', data);
+
+  assert.deepEqual(sent[0], {
+    app: 'youle', route: 'fixture-route', rpc: 'play-card', data: { card: 7 },
+  });
+  assert.equal(sent[0]!.data, data);
+  assert.equal(host.sendGameMessage.length, 2, 'Host API 不接受 route');
+  assert.throws(() => host.sendGameMessage('', {}), /rpc.*non-empty/i);
+  assert.throws(() => host.sendGameMessage('   ', {}), /rpc.*non-empty/i);
+  assert.equal(sent.length, 1);
+});
+
+test('adapter rejects empty and reserved GameEntry routes before exposing a Host', () => {
+  for (const route of ['', '   ', 'platform', 'agent', 'room']) {
+    assert.throws(
+      () => makeLease({ gameEntry: entry(route) }),
+      route.trim() === '' ? /route.*non-empty/i : /reserved.*route/i,
+    );
+  }
+});
+
+test('execute exposes only the GameHost command union and delegates semantic commands', () => {
+  const { host, sent } = makeLease({ store: roomStore(4, 1, 0) });
+
+  host.execute({ type: 'room.prepare' });
+  host.execute({ type: 'room.exit' });
+
+  assert.equal(sent[0]!.rpc, 'player_prepare');
+  assert.equal(sent[1]!.rpc, 'self_exit_room');
+  assert.throws(
+    () => host.execute({ type: 'room.join' } as unknown as GameHostCommand),
+    /unsupported.*command/i,
+  );
+  assert.equal(sent.length, 2);
+});
+
+test('seat mapper binds each 2, 4, and 10 seat session and round-trips every server seat', () => {
+  for (const seatCount of [2, 4, 10]) {
+    const selfSeat = seatCount - 1;
+    const { host } = makeLease({ store: roomStore(seatCount, selfSeat) });
+    assert.equal(host.seat.toView(selfSeat), 0);
+    for (let serverSeat = 0; serverSeat < seatCount; serverSeat++) {
+      const viewSeat = (serverSeat - selfSeat + seatCount) % seatCount;
+      assert.equal(host.seat.toView(serverSeat), viewSeat);
+      assert.equal(host.seat.toServer(viewSeat), serverSeat);
+    }
+    for (const invalid of [-1, seatCount, 0.5, Number.NaN, Number.POSITIVE_INFINITY, '0']) {
+      assert.throws(() => host.seat.toView(invalid as number), /seat.*range|integer/i);
+      assert.throws(() => host.seat.toServer(invalid as number), /seat.*range|integer/i);
+    }
+  }
+});
+
+test('adapter validates descriptor seat count against the canonical room session', () => {
+  const store = roomStore(4, 1);
+  for (const seatCount of [0, -1, 2.5, Number.NaN, 2]) {
+    assert.throws(
+      () => makeLease({
+        store,
+        gameEntry: { ...entry(), resolveSeatCount: () => seatCount },
+      }),
+      /seat count/i,
+    );
+  }
+});
+
+test('getSnapshot exposes only recursively frozen SDK DTOs and the canonical roomtype', () => {
+  const { host, store } = makeLease();
+  const state = store.getState();
+  assert.equal(state.room.kind, 'inside');
+  if (state.room.kind !== 'inside') return;
+
+  const snapshot = host.getSnapshot();
+
+  assert.deepEqual(Object.keys(snapshot).sort(), ['connection', 'room', 'seats', 'self']);
+  assert.equal(snapshot.room.roomtype, state.room.roomtype);
+  assert.equal(Object.isFrozen(snapshot), true);
+  assert.equal(Object.isFrozen(snapshot.connection), true);
+  assert.equal(Object.isFrozen(snapshot.self), true);
+  assert.equal(Object.isFrozen(snapshot.room), true);
+  assert.equal(Object.isFrozen(snapshot.room.roomtype), true);
+  assert.equal(Object.isFrozen(snapshot.room.roomtype[1]), true);
+  assert.equal(Object.isFrozen((snapshot.room.roomtype[1] as { nested: unknown[] }).nested), true);
+  assert.equal(Object.isFrozen(snapshot.seats), true);
+  assert.equal(Object.isFrozen(snapshot.seats[0]), true);
+  assert.equal('getState' in snapshot, false);
+  assert.equal('subscribe' in snapshot, false);
+  assert.equal('state' in snapshot, false);
+});
+
+class ObservableStore extends PlatformStore {
+  private readonly observed = new Set<(state: PlatformState, previous: PlatformState) => void>();
+
+  override subscribe(listener: (state: PlatformState, previous: PlatformState) => void): () => void {
+    const unsubscribeStore = super.subscribe(listener);
+    this.observed.add(listener);
+    return () => {
+      this.observed.delete(listener);
+      unsubscribeStore();
+    };
+  }
+
+  emitCurrent(): void {
+    const state = this.getState();
+    for (const listener of [...this.observed]) listener(state, state);
+  }
+}
+
+test('subscribe is immediate, suppresses identical public snapshots, and isolates listener failures', () => {
+  const store = new ObservableStore();
+  const source = fixture('player-login-room.json');
+  source.data.isbattle = 0;
+  source.data.roomtype = [4];
+  store.applyLoginSuccess(parseLoginResponse(source.data));
+  const { host } = makeLease({ store });
+  const received: unknown[] = [];
+
+  host.subscribe((snapshot) => { received.push(snapshot); });
+  store.emitCurrent();
+  assert.equal(received.length, 1);
+
+  const listenerFailure = new Error('listener failed');
+  const reports: unknown[][] = [];
+  const originalConsoleError = console.error;
+  console.error = (...args: unknown[]) => { reports.push(args); };
+  try {
+    assert.throws(
+      () => host.subscribe(() => { throw listenerFailure; }),
+      (error) => error === listenerFailure,
+    );
+    store.playerJoin(parseOtherJoinRoomPayload({
+      seat: 2, playerid: 77, nickname: 'other', avatar: 'http://b',
+      sex: 1, bean: 90, ip: '127.0.0.2', onstate: 0, isprepare: 0,
+    }));
+    assert.equal(received.length, 2);
+    assert.equal(reports.length, 0, 'failed initial subscriptions must be removed');
+  } finally {
+    console.error = originalConsoleError;
+  }
+});
+
+test('a later listener failure does not block other Host subscribers', () => {
+  const { host, store } = makeLease();
+  const listenerFailure = new Error('later listener failed');
+  let firstCalls = 0;
+  let secondCalls = 0;
+  const reports: unknown[][] = [];
+  const originalConsoleError = console.error;
+  console.error = (...args: unknown[]) => { reports.push(args); };
+  try {
+    host.subscribe(() => {
+      firstCalls++;
+      if (firstCalls > 1) throw listenerFailure;
+    });
+    host.subscribe(() => { secondCalls++; });
+
+    store.playerJoin(parseOtherJoinRoomPayload({
+      seat: 2, playerid: 77, nickname: 'other', avatar: 'http://b',
+      sex: 1, bean: 90, ip: '127.0.0.2', onstate: 0, isprepare: 0,
+    }));
+
+    assert.equal(firstCalls, 2);
+    assert.equal(secondCalls, 2);
+    assert.equal(reports.length, 1);
+    assert.equal(reports[0]!.includes(listenerFailure), true);
+  } finally {
+    console.error = originalConsoleError;
+  }
+});
+
+class ThrowingUnsubscribeStore extends PlatformStore {
+  unsubscribeCalls = 0;
+
+  override subscribe(listener: (state: PlatformState, previous: PlatformState) => void): () => void {
+    const unsubscribeStore = super.subscribe(listener);
+    return () => {
+      unsubscribeStore();
+      this.unsubscribeCalls++;
+      if (this.unsubscribeCalls === 1) throw undefined;
+      throw null;
+    };
+  }
+}
+
+test('invalidate clears every subscription and reference before reporting all cleanup failures', () => {
+  const store = new ThrowingUnsubscribeStore();
+  const source = fixture('player-login-room.json');
+  source.data.isbattle = 0;
+  source.data.roomtype = [4];
+  store.applyLoginSuccess(parseLoginResponse(source.data));
+  const { host, invalidate } = makeLease({ store });
+  let callbacks = 0;
+  const firstUnsubscribe = host.subscribe(() => { callbacks++; });
+  const secondUnsubscribe = host.subscribe(() => { callbacks++; });
+
+  let cleanupError: unknown;
+  try {
+    invalidate();
+  } catch (error) {
+    cleanupError = error;
+  }
+
+  assert.equal(store.unsubscribeCalls, 2);
+  assert.deepEqual(
+    (cleanupError as { errors?: readonly unknown[] })?.errors,
+    [undefined, null],
+  );
+  assert.throws(() => host.getSnapshot(), GameSessionDisposedError);
+  assert.doesNotThrow(() => firstUnsubscribe());
+  assert.doesNotThrow(() => secondUnsubscribe());
+  assert.doesNotThrow(() => invalidate());
+  store.playerJoin(parseOtherJoinRoomPayload({
+    seat: 2, playerid: 77, nickname: 'other', avatar: 'http://b',
+    sex: 1, bean: 90, ip: '127.0.0.2', onstate: 0, isprepare: 0,
+  }));
+  assert.equal(callbacks, 2);
+});
+
+test('unsubscribe and invalidate are reentry-safe and prevent callbacks already snapshotted by Store', () => {
+  const { host, invalidate, store } = makeLease();
+  const calls: string[] = [];
+  let unsubscribeSecond = (): void => undefined;
+  host.subscribe(() => {
+    calls.push('first');
+    if (calls.length > 2) {
+      unsubscribeSecond();
+      invalidate();
+    }
+  });
+  unsubscribeSecond = host.subscribe(() => { calls.push('second'); });
+  assert.deepEqual(calls, ['first', 'second']);
+
+  store.playerJoin(parseOtherJoinRoomPayload({
+    seat: 2, playerid: 77, nickname: 'other', avatar: 'http://b',
+    sex: 1, bean: 90, ip: '127.0.0.2', onstate: 0, isprepare: 0,
+  }));
+
+  assert.deepEqual(calls, ['first', 'second', 'first']);
+  assert.doesNotThrow(() => unsubscribeSecond());
+  assert.doesNotThrow(() => unsubscribeSecond());
+  assert.doesNotThrow(() => invalidate());
+  store.playerReady(parsePlayerPreparePayload({ seat: 2 }));
+  assert.deepEqual(calls, ['first', 'second', 'first']);
+});
+
+test('invalidate is idempotent, old unsubscribe stays safe, and every stale Host method fails predictably', () => {
+  const { host, invalidate, store, sent } = makeLease();
+  let callbacks = 0;
+  const unsubscribe = host.subscribe(() => { callbacks++; });
+  assert.equal(callbacks, 1);
+
+  invalidate();
+  invalidate();
+
+  const disposed = (call: () => unknown) => assert.throws(call, GameSessionDisposedError);
+  disposed(() => host.getSnapshot());
+  disposed(() => host.subscribe(() => { callbacks++; }));
+  disposed(() => host.subscribe(null as never));
+  disposed(() => host.sendGameMessage('play-card', {}));
+  disposed(() => host.execute({ type: 'room.prepare' }));
+  disposed(() => host.seat.toView(0));
+  disposed(() => host.seat.toServer(0));
+  assert.doesNotThrow(() => unsubscribe());
+  assert.doesNotThrow(() => unsubscribe());
+
+  store.playerJoin(parseOtherJoinRoomPayload({
+    seat: 2, playerid: 77, nickname: 'other', avatar: 'http://b',
+    sex: 1, bean: 90, ip: '127.0.0.2', onstate: 0, isprepare: 0,
+  }));
+  assert.equal(callbacks, 1);
+  assert.equal(sent.length, 0);
+});
diff --git a/cocoscreator_projects/framework-tests/sdk/game-contract-harness.test.ts b/cocoscreator_projects/framework-tests/sdk/game-contract-harness.test.ts
index 8a3d96c..7b7fe19 100644
--- a/cocoscreator_projects/framework-tests/sdk/game-contract-harness.test.ts
+++ b/cocoscreator_projects/framework-tests/sdk/game-contract-harness.test.ts
@@ -1,10 +1,16 @@
 import assert from 'node:assert/strict';
+import { readFileSync } from 'node:fs';
 import { test } from 'node:test';
+import type { RuntimeConfig } from '../../YouleNexus/assets/framework/config/runtime-config.ts';
+import type { OutboundEnvelope } from '../../YouleNexus/assets/framework/core/types/envelope.ts';
+import { createGameHostAdapter } from '../../YouleNexus/assets/framework/platform/game-host-adapter.ts';
+import { PlatformCommands } from '../../YouleNexus/assets/framework/platform/commands.ts';
+import { PlatformStore } from '../../YouleNexus/assets/framework/platform/stores/platform-store.ts';
+import { parseLoginResponse } from '../../YouleNexus/assets/framework/protocol/contracts/index.ts';
 import type {
   GameEntry,
   GameHost,
   GameModule,
-  PlatformGameSnapshot,
 } from '../../YouleNexus/assets/framework/sdk/contracts/index.ts';
 import {
   assertGameContract,
@@ -29,13 +35,26 @@ test('assertGameContract runs the reusable isolated session conformance suite',
 
   assert.doesNotThrow(() => assertGameContract(
     entry,
-    makeConformanceHost(() => { invalidations++; }, restoredDeskinfo),
+    makeConformanceHost(entry, () => { invalidations++; }, restoredDeskinfo),
   ));
   assert.equal(invalidations, 2);
   assert.equal(restoredDeskinfo.length, 0);
   assert.ok(nextModuleId >= 2);
 });
 
+const RUNTIME_CONFIG: RuntimeConfig = Object.freeze({
+  mode: 'release',
+  isDebugger: false,
+  identity: Object.freeze({
+    agentid: 'fixture-agent', channelid: 'fixture-channel', gameid: '41',
+    marketid: 'fixture-market', version: 41,
+  }),
+  servers: Object.freeze(['ws://fixture']),
+  source: 'remote',
+  gameserver: 'https://fixture/config',
+  rawConfig: Object.freeze({ data: Object.freeze({ urlserver: 'fixture' }) }),
+});
+
 function makeModule(id: number, onRestore: (deskinfo: unknown) => void): GameModule {
   let host: GameHost | undefined;
   let restored: unknown;
@@ -77,25 +96,29 @@ function deskinfoFor(cycle: number): { readonly cycle: number } {
 }
 
 function makeConformanceHost(
+  entry: GameEntry,
   onInvalidate: () => void,
   restoredDeskinfo: unknown[],
 ): () => GameContractHost {
   return () => {
-    const snapshot: PlatformGameSnapshot = {
-      connection: { phase: 'connected' },
-      self: { playerId: 1, seat: 0 },
-      room: { roomcode: 'fixture', roomtype: [], stage: 0, needprepare: 0, infinite: 0 },
-      seats: [],
-    };
+    const login = JSON.parse(readFileSync(
+      new URL('../fixtures/contracts/player-login-room.json', import.meta.url),
+      'utf8',
+    )) as { data: Record<string, unknown> };
+    login.data.roomtype = [4];
+    login.data.isbattle = 0;
+    const store = new PlatformStore();
+    store.applyLoginSuccess(parseLoginResponse(login.data));
+    const sent: OutboundEnvelope[] = [];
+    const send = { send: (envelope: OutboundEnvelope) => { sent.push(envelope); } };
+    const commands = new PlatformCommands({ runtimeConfig: RUNTIME_CONFIG, store, send });
+    const lease = createGameHostAdapter({ gameEntry: entry, store, commands, send });
     return {
-      host: {
-        seat: { toView: (seat) => seat, toServer: (seat) => seat },
-        getSnapshot: () => snapshot,
-        subscribe: () => () => {},
-        sendGameMessage: () => {},
-        execute: () => {},
+      host: lease.host,
+      invalidate() {
+        lease.invalidate();
+        onInvalidate();
       },
-      invalidate: onInvalidate,
       assertRestored(deskinfo) {
         assert.equal(restoredDeskinfo.shift(), deskinfo);
       },