diff --git a/packages/cli/cli.js b/packages/cli/cli.js
index b170f09..91b5d66 100644
--- a/packages/cli/cli.js
+++ b/packages/cli/cli.js
@@ -95,4 +95,4 @@ async function main() {
   }
 }
 
-main()
+main().then(exit)
diff --git a/server/quests/helloworld/game.yml b/server/quests/helloworld/game.yml
index 8db3f1e..d7f6f47 100644
--- a/server/quests/helloworld/game.yml
+++ b/server/quests/helloworld/game.yml
@@ -5,7 +5,7 @@ introduction: |
 
   「輸入 echo Hello World!」
 stages:
-  - name: helloworld
+  - id: helloworld
     condition:
       command:
         - echo Hello World!
@@ -19,3 +19,11 @@ stages:
       - 例如，你可以輸入 `ls` 來查看目前的目錄下有哪些檔案。
     hint:
       - 使用 `ls` 指令來查看目前的目錄下有哪些檔案。
+    next: ls
+  - id: ls
+    condition:
+      command:
+        - ls
+    responses:
+      - NOTHING
+    next: END
diff --git a/server/src/api/controllers/commandController.js b/server/src/api/controllers/commandController.js
index 7cfbb0c..d4deabe 100644
--- a/server/src/api/controllers/commandController.js
+++ b/server/src/api/controllers/commandController.js
@@ -2,6 +2,7 @@
 import Command from '../../models/command.js'
 import Session from '../../models/session.js'
 import { verifySessionJWT } from '../../utils/auth.js'
+import commandHandler from '../../game/commandHandler.js'
 
 export async function newCommand(req, res) {
   console.log('new command:', req.body)
@@ -38,7 +39,8 @@ export async function newCommand(req, res) {
 
   await c.save()
 
-  res.status(201).json({
-    responses: ['Hello, world!', 'How are you?'],
-  })
+  const response = await commandHandler(session, c)
+  console.log(response)
+
+  res.status(201).json(response)
 }
diff --git a/server/src/api/controllers/sessionController.js b/server/src/api/controllers/sessionController.js
index 81e163f..79b0940 100644
--- a/server/src/api/controllers/sessionController.js
+++ b/server/src/api/controllers/sessionController.js
@@ -23,9 +23,11 @@ export async function createSession(req, res) {
   }
 
   try {
+    const progress = quest.stages[0].id
     const newSession = new Session({
       user: req.user,
       quest,
+      progress,
       containerId: `quest-${quest.id}-${req.user.username}-${Date.now()}`,
     })
 
diff --git a/server/src/game/commandHandler.js b/server/src/game/commandHandler.js
new file mode 100644
index 0000000..c5d2c5b
--- /dev/null
+++ b/server/src/game/commandHandler.js
@@ -0,0 +1,42 @@
+import Quest from '../models/quest.js'
+
+// 檢查 pattern 是否符合 input
+const checkMatch = (pattern, input) => {
+  if (pattern.length === 0) return true
+  return pattern.some((p) => {
+    const regex = new RegExp(p)
+    return regex.test(input)
+  })
+}
+
+const commandHandler = async (session, commandInput) => {
+  const quest = await Quest.findById(session.quest)
+  const stage = quest.stages.find((s) => s.id === session.progress)
+  if (!stage) {
+    console.error('stage not found', session.progress)
+    return {}
+  }
+
+  console.log(stage.condition)
+
+  const commandMatch = checkMatch(stage.condition.command, commandInput.command)
+  const outputMatch = checkMatch(stage.condition.output, commandInput.output)
+  const errorMatch = checkMatch(stage.condition.error, commandInput.output)
+
+  console.log(commandMatch, outputMatch, errorMatch)
+
+  if (!commandMatch || !outputMatch || !errorMatch) return {}
+
+  session.completion.push(session.progress)
+
+  const nextStage = quest.stages.find((s) => s.id === stage.next)
+  session.progress = nextStage.id
+  await session.save()
+
+  return {
+    responses: stage.responses,
+    hint: stage.hint,
+  }
+}
+
+export default commandHandler
diff --git a/server/src/models/quest.js b/server/src/models/quest.js
index d16804d..7c68866 100644
--- a/server/src/models/quest.js
+++ b/server/src/models/quest.js
@@ -1,7 +1,7 @@
 import { model, Schema } from 'mongoose'
 
 const stageSchema = new Schema({
-  name: {
+  id: {
     type: String,
     required: true,
   },
@@ -27,6 +27,10 @@ const stageSchema = new Schema({
     type: [String],
     required: true,
   },
+  next: {
+    type: String,
+    required: true,
+  },
 })
 
 const Quest = model(
diff --git a/server/src/models/session.js b/server/src/models/session.js
index 62ccdf6..c1b813e 100644
--- a/server/src/models/session.js
+++ b/server/src/models/session.js
@@ -14,6 +14,8 @@ const Session = model(
       },
       containerId: String,
       finishedAt: Date,
+      progress: String,
+      completion: [String],
     },
     { timestamps: true }
   )