diff --git a/plugins/sandbox/package.json b/plugins/sandbox/package.json
index e01c9af8..55131a39 100644
--- a/plugins/sandbox/package.json
+++ b/plugins/sandbox/package.json
@@ -1,7 +1,7 @@
 {
   "name": "@koishijs/plugin-sandbox",
   "description": "Test Your Virtual Bot in Console",
-  "version": "3.3.1",
+  "version": "3.4.0",
   "main": "lib/index.js",
   "typings": "lib/index.d.ts",
   "files": [
diff --git a/plugins/sandbox/src/bot.ts b/plugins/sandbox/src/bot.ts
index 1e94e0cb..45efa477 100644
--- a/plugins/sandbox/src/bot.ts
+++ b/plugins/sandbox/src/bot.ts
@@ -14,9 +14,8 @@ export class SandboxBot<C extends Context = Context> extends Bot<C, SandboxBot.C
 
   hidden = true
   internal = {}
-  clients = new Set<Client>()
 
-  constructor(ctx: C, config: SandboxBot.Config) {
+  constructor(ctx: C, public client: Client, config: SandboxBot.Config) {
     super(ctx, config)
     this.selfId = config.selfId
     this.platform = config.platform
@@ -24,7 +23,6 @@ export class SandboxBot<C extends Context = Context> extends Bot<C, SandboxBot.C
   }
 
   async request<T = any>(method: string, data = {}) {
-    const client = [...this.clients][0]
     const nonce = Math.random().toString(36).slice(2)
     return new Promise<T>((resolve, reject) => {
       const dispose1 = this.ctx.on('sandbox/response', (nonce2, data) => {
@@ -38,7 +36,7 @@ export class SandboxBot<C extends Context = Context> extends Bot<C, SandboxBot.C
         dispose2()
         reject(new Error('timeout'))
       }, Time.second * 5)
-      client.send({
+      this.client.send({
         type: 'sandbox/request',
         body: { method, data, nonce },
       })
diff --git a/plugins/sandbox/src/index.ts b/plugins/sandbox/src/index.ts
index 8b98a07f..4f32cf99 100644
--- a/plugins/sandbox/src/index.ts
+++ b/plugins/sandbox/src/index.ts
@@ -1,5 +1,5 @@
 import { $, Context, Dict, Random, Schema, Universal, User } from 'koishi'
-import { DataService } from '@koishijs/console'
+import { Client, DataService } from '@koishijs/console'
 import { resolve } from 'path'
 import { SandboxBot } from './bot'
 import zhCN from './locales/zh-CN.yml'
@@ -87,12 +87,16 @@ export function apply(ctx: Context, config: Config) {
     }
   }
 
-  ctx.console.addListener('sandbox/send-message', async function (platform, userId, channel, content, quote) {
-    const bot = bots[platform] ||= new SandboxBot(ctx, {
+  const ensureBot = (platform: string, client: Client) => {
+    // assert unique platform
+    return bots[platform] ||= new SandboxBot(ctx, client, {
       platform,
       selfId: 'koishi',
     })
-    bot.clients.add(this)
+  }
+
+  ctx.console.addListener('sandbox/send-message', async function (platform, userId, channel, content, quote) {
+    const bot = ensureBot(platform, this)
     const id = Random.id()
     this.send({
       type: 'sandbox/message',
@@ -110,11 +114,7 @@ export function apply(ctx: Context, config: Config) {
   }, { authority: 4 })
 
   ctx.console.addListener('sandbox/delete-message', async function (platform, userId, channel, messageId) {
-    const bot = bots[platform] ||= new SandboxBot(ctx, {
-      platform,
-      selfId: 'koishi',
-    })
-    bot.clients.add(this)
+    const bot = ensureBot(platform, this)
     const session = bot.session(createEvent(userId, channel))
     session.type = 'message-deleted'
     session.messageId = messageId
@@ -132,6 +132,15 @@ export function apply(ctx: Context, config: Config) {
   }, { authority: 4 })
 
   ctx.console.addListener('sandbox/set-user', async function (platform, pid, data) {
+    const bot = ensureBot(platform, this)
+    const session = bot.session(createEvent(pid, '#'))
+    if (data) {
+      session.type = 'guild-member-added'
+      ctx.emit('guild-member-added', session)
+    } else {
+      session.type = 'guild-member-removed'
+      ctx.emit('guild-member-removed', session)
+    }
     const database = ctx.get('database')
     if (!database) return
     const [binding] = await database.get('binding', { platform, pid }, ['aid'])
@@ -158,10 +167,8 @@ export function apply(ctx: Context, config: Config) {
 
   ctx.on('console/connection', async (client) => {
     if (ctx.console.clients[client.id]) return
-    for (const platform of Object.keys(bots)) {
-      const bot = bots[platform]
-      bot.clients.delete(client)
-      if (!bot.clients.size) {
+    for (const [platform, bot] of Object.entries(bots)) {
+      if (bot.client === client) {
         delete bots[platform]
         delete ctx.bots[bot.sid]
       }
@@ -173,10 +180,8 @@ export function apply(ctx: Context, config: Config) {
   ctx.intersect(session => session.platform.startsWith('sandbox:'))
     .command('clear')
     .action(({ session }) => {
-      for (const client of (session.bot as SandboxBot).clients) {
-        client.send({
-          type: 'sandbox/clear',
-        })
-      }
+      (session.bot as SandboxBot).client.send({
+        type: 'sandbox/clear',
+      })
     })
 }
diff --git a/plugins/sandbox/src/message.ts b/plugins/sandbox/src/message.ts
index 731c350d..7d8cff47 100644
--- a/plugins/sandbox/src/message.ts
+++ b/plugins/sandbox/src/message.ts
@@ -21,18 +21,16 @@ export class SandboxMessenger<C extends Context = Context> extends MessageEncode
     const content = await h.transformAsync(this.buffer.trim(), this.rules)
     const session = this.bot.session(this.session.event)
     session.messageId = Random.id()
-    for (const client of this.bot.clients) {
-      client.send({
-        type: 'sandbox/message',
-        body: {
-          content,
-          user: 'Koishi',
-          channel: session.channelId,
-          id: session.messageId,
-          platform: session.platform,
-        },
-      })
-    }
+    this.bot.client.send({
+      type: 'sandbox/message',
+      body: {
+        content,
+        user: 'Koishi',
+        channel: session.channelId,
+        id: session.messageId,
+        platform: session.platform,
+      },
+    })
     this.results.push(session.event.message)
     this.buffer = ''
   }