diff --git a/packages/constants/src/index.ts b/packages/constants/src/index.ts
index 2380b82..8d1f50e 100644
--- a/packages/constants/src/index.ts
+++ b/packages/constants/src/index.ts
@@ -1,6 +1,6 @@
 import { z } from 'zod'
 
-export * from './quest.js'
+export * from './quest/index.js'
 export * from './session.js'
 
 export const passwordPolicy = {
diff --git a/packages/constants/src/quest.ts b/packages/constants/src/quest.ts
deleted file mode 100644
index 69adbe0..0000000
--- a/packages/constants/src/quest.ts
+++ /dev/null
@@ -1,6 +0,0 @@
-export interface QuestDetailResponse {
-  _id: string
-  title: string
-  instruction: string
-  requirements: string[]
-}
diff --git a/packages/constants/src/quest/command-responder.ts b/packages/constants/src/quest/command-responder.ts
new file mode 100644
index 0000000..bbba51a
--- /dev/null
+++ b/packages/constants/src/quest/command-responder.ts
@@ -0,0 +1,11 @@
+import { z } from 'zod'
+import { conditionSchema } from './condition.js'
+import { responseSchema } from './response.js'
+
+export const commandResponderSchema = z.object({
+  condition: conditionSchema.optional(),
+  responses: z.array(responseSchema),
+  hints: z.array(z.string()),
+})
+
+export type CommandResponder = z.infer<typeof commandResponderSchema>
diff --git a/packages/constants/src/quest/condition.ts b/packages/constants/src/quest/condition.ts
new file mode 100644
index 0000000..a3405c0
--- /dev/null
+++ b/packages/constants/src/quest/condition.ts
@@ -0,0 +1,12 @@
+import { z } from 'zod'
+import { fileConditionSchema } from './file-condition.js'
+
+export const conditionSchema = z.object({
+  command: z.array(z.string()).optional(),
+  output: z.array(z.string()).optional(),
+  error: z.array(z.string()).optional(),
+  pwd: z.array(z.string()).optional(),
+  files: z.array(fileConditionSchema).optional(),
+})
+
+export type Condition = z.infer<typeof conditionSchema>
diff --git a/packages/constants/src/quest/file-condition.ts b/packages/constants/src/quest/file-condition.ts
new file mode 100644
index 0000000..e86fe24
--- /dev/null
+++ b/packages/constants/src/quest/file-condition.ts
@@ -0,0 +1,9 @@
+import { z } from 'zod'
+
+export const fileConditionSchema = z.object({
+  path: z.string(),
+  type: z.string().optional(),
+  exists: z.boolean().default(true),
+})
+
+export type FileCondition = z.infer<typeof fileConditionSchema>
diff --git a/packages/constants/src/quest/global-exception.ts b/packages/constants/src/quest/global-exception.ts
new file mode 100644
index 0000000..92d1038
--- /dev/null
+++ b/packages/constants/src/quest/global-exception.ts
@@ -0,0 +1,11 @@
+import { z } from 'zod'
+import { conditionSchema } from './condition.js'
+import { responseSchema } from './response.js'
+
+export const globalExceptionSchema = z.object({
+  condition: conditionSchema,
+  responses: z.array(responseSchema),
+  requirements: z.array(z.string()),
+})
+
+export type GlobalException = z.infer<typeof globalExceptionSchema>
diff --git a/packages/constants/src/quest/hint.ts b/packages/constants/src/quest/hint.ts
new file mode 100644
index 0000000..49f3852
--- /dev/null
+++ b/packages/constants/src/quest/hint.ts
@@ -0,0 +1,5 @@
+import { z } from 'zod'
+
+export const hintSchema = z.array(z.string())
+
+export type Hint = z.infer<typeof hintSchema>
diff --git a/packages/constants/src/quest/index.ts b/packages/constants/src/quest/index.ts
new file mode 100644
index 0000000..0dc6cf7
--- /dev/null
+++ b/packages/constants/src/quest/index.ts
@@ -0,0 +1,11 @@
+export * from './requirement.js'
+export * from './hint.js'
+export * from './file-condition.js'
+export * from './condition.js'
+export * from './response.js'
+export * from './command-responder.js'
+export * from './stage-exception.js'
+export * from './stage.js'
+export * from './global-exception.js'
+export * from './quest.js'
+export * from './quest-detail-response.js'
diff --git a/packages/constants/src/quest/quest-detail-response.ts b/packages/constants/src/quest/quest-detail-response.ts
new file mode 100644
index 0000000..ddc5e1c
--- /dev/null
+++ b/packages/constants/src/quest/quest-detail-response.ts
@@ -0,0 +1,10 @@
+import { z } from 'zod'
+
+export const questDetailResponseSchema = z.object({
+  _id: z.string(),
+  title: z.string(),
+  instruction: z.string(),
+  requirements: z.array(z.string()),
+})
+
+export type QuestDetailResponse = z.infer<typeof questDetailResponseSchema>
diff --git a/packages/constants/src/quest/quest.ts b/packages/constants/src/quest/quest.ts
new file mode 100644
index 0000000..e8d0440
--- /dev/null
+++ b/packages/constants/src/quest/quest.ts
@@ -0,0 +1,16 @@
+import { z } from 'zod'
+import { stageSchema } from './stage.js'
+import { globalExceptionSchema } from './global-exception.js'
+import { requirementSchema } from './requirement.js'
+
+export const questSchema = z.object({
+  id: z.string(),
+  title: z.string(),
+  image: z.string(),
+  instruction: z.string(),
+  requirements: requirementSchema,
+  stages: z.array(stageSchema),
+  exceptions: z.array(globalExceptionSchema).default([]),
+})
+
+export type Quest = z.infer<typeof questSchema>
diff --git a/packages/constants/src/quest/requirement.ts b/packages/constants/src/quest/requirement.ts
new file mode 100644
index 0000000..f702582
--- /dev/null
+++ b/packages/constants/src/quest/requirement.ts
@@ -0,0 +1,5 @@
+import { z } from 'zod'
+
+export const requirementSchema = z.array(z.string()).default([])
+
+export type Requirement = z.infer<typeof requirementSchema>
diff --git a/packages/constants/src/quest/response.ts b/packages/constants/src/quest/response.ts
new file mode 100644
index 0000000..79f72ce
--- /dev/null
+++ b/packages/constants/src/quest/response.ts
@@ -0,0 +1,8 @@
+import { z } from 'zod'
+
+export const responseSchema = z.object({
+  type: z.enum(['narrative', 'dialogue']).default('narrative'),
+  content: z.string(),
+})
+
+export type Response = z.infer<typeof responseSchema>
diff --git a/packages/constants/src/quest/stage-exception.ts b/packages/constants/src/quest/stage-exception.ts
new file mode 100644
index 0000000..fd0415d
--- /dev/null
+++ b/packages/constants/src/quest/stage-exception.ts
@@ -0,0 +1,10 @@
+import { z } from 'zod'
+import { conditionSchema } from './condition.js'
+import { responseSchema } from './response.js'
+
+export const stageExceptionSchema = z.object({
+  condition: conditionSchema,
+  responses: z.array(responseSchema),
+})
+
+export type StageException = z.infer<typeof stageExceptionSchema>
diff --git a/packages/constants/src/quest/stage.ts b/packages/constants/src/quest/stage.ts
new file mode 100644
index 0000000..841611e
--- /dev/null
+++ b/packages/constants/src/quest/stage.ts
@@ -0,0 +1,18 @@
+import { z } from 'zod'
+import { stageExceptionSchema } from './stage-exception.js'
+import { conditionSchema } from './condition.js'
+import { responseSchema } from './response.js'
+import { hintSchema } from './hint.js'
+import { requirementSchema } from './requirement.js'
+
+export const stageSchema = z.object({
+  id: z.string(),
+  task: z.string(),
+  exceptions: z.array(stageExceptionSchema).default([]),
+  requirements: requirementSchema,
+  condition: conditionSchema,
+  responses: z.array(responseSchema),
+  hints: hintSchema.default([]),
+})
+
+export type Stage = z.infer<typeof stageSchema>
diff --git a/packages/constants/tests/condition.test.ts b/packages/constants/tests/condition.test.ts
new file mode 100644
index 0000000..60b388a
--- /dev/null
+++ b/packages/constants/tests/condition.test.ts
@@ -0,0 +1,13 @@
+import { describe, it, expect } from '@jest/globals'
+import { conditionSchema } from '../src/index.js'
+
+describe('parsing condition', () => {
+  it('should parse condition', () => {
+    const condition = {
+      command: ['^echo start$'],
+      output: ['^start$'],
+    }
+    const result = conditionSchema.safeParse(condition)
+    expect(result.error).toBeUndefined()
+  })
+})
diff --git a/packages/constants/tests/quest.test.ts b/packages/constants/tests/quest.test.ts
new file mode 100644
index 0000000..bccc3b5
--- /dev/null
+++ b/packages/constants/tests/quest.test.ts
@@ -0,0 +1,93 @@
+import { describe, it, expect } from '@jest/globals'
+import { questSchema } from '../src/index.js'
+
+describe('Test quest schema', () => {
+  it('should parse quest schema', () => {
+    const sampleQuest = {
+      id: 'get-started',
+      image: 'base',
+      title: '終端機的基本知識',
+      instruction: `歡迎來到 Linux Odyssey！
+  在這個關卡中，你將會學到：
+  1. 如何使用這個網站
+  2. 如何使用終端機`,
+      stages: [
+        {
+          id: 'start',
+          task: '按下 `開始` ����開始',
+          condition: {
+            command: ['^echo start$'],
+          },
+          responses: [
+            {
+              content: `在畫面的中下方的區��是終端機，你可以在終端機��輸入指令來操作電��。
+  在終端機中，你所看到的 \`commander:~ $\` 叫做命令提示字串。
+  ��令提示字串最後的��字號 \`$\` 叫命令提示符，你必須將指令輸入在它的後方。
+  ��你輸入完指令並按下 Enter 之後，終端機會��行你輸入的指令，並且會從終端機的下一行開始輸出指令的��行結果。
+  直到你看到新的 \`commander:~ $\` 出現時，代表你可以輸入下一個指令了。
+  ��在請你輸入 \`echo hello\` 來看看會發生什麼事。`,
+            },
+          ],
+          hints: ['��  在 `commander:~ $` ��面輸入 `echo hello` ��按下 Enter'],
+        },
+        {
+          id: 'echo-hello',
+          task: '在終端機輸入 `echo hello`',
+          requirements: ['start'],
+          condition: {
+            command: ['^echo hello$'],
+          },
+          responses: [
+            {
+              content: `你應��可以看到終端機上��示了以下內容：
+  \`\`\`
+  commander:~ $ echo hello
+  hello
+  \`\`\`
+  第一行的 \`commander:~ $\` 是命令提示字串，接在後方的 \`echo hello\` 是你輸入的指令。
+  第二行的 \`hello\` ��是終端機的輸出結果。
+  你現在知道了如何在終端機上輸入指令，以及查看終端機輸出的位置。
+  ��在請輸入 \`echo next\` 來��續下一個步��。`,
+            },
+          ],
+          hints: ['��  ���入 `echo next` ���續下一個步��'],
+        },
+        {
+          id: 'echo-next',
+          task: '在終端機輸入 `echo next`',
+          requirements: ['echo-hello'],
+          condition: {
+            command: ['^echo next$'],
+          },
+          responses: [
+            {
+              content: `\`Ctrl + C\` 在終端機中是一個很重要的快捷鍵，它可以用來中��正在��行的指令，並產生一個新的命令提示字串，讓你可以��續輸入指令。
+  如果指令��行很久沒有反應，或你因為其他原因想要中��指令，你可以按下 \`Ctrl + C\` 來中��指令。
+  又或者你輸入了錯��的指令，����得慢慢��除，你也可以按下 \`Ctrl + C\` 來產生新的命令提示字串重新輸入指令。
+  如果你已經理解了��才的說明，請輸入 \`echo finish\` 來結束這一關。`,
+            },
+          ],
+          hints: [
+            '��  ��下 `Ctrl + C` 能��中��正在��行的指令',
+            '��  ��下 `Ctrl + C` 能��產生新的命令提示字串',
+            '��  ���入 `echo finish` 來結束這一關',
+          ],
+        },
+        {
+          id: 'END',
+          task: '結束關卡',
+          requirements: ['echo-next'],
+          condition: {
+            command: ['^echo finish$'],
+          },
+          responses: [
+            {
+              content: '恭喜你完成了這個關卡！',
+            },
+          ],
+        },
+      ],
+    }
+    expect(questSchema.safeParse(sampleQuest).error).toBeUndefined()
+  })
+})
diff --git a/packages/constants/tests/response.test.ts b/packages/constants/tests/response.test.ts
new file mode 100644
index 0000000..eb3eb15
--- /dev/null
+++ b/packages/constants/tests/response.test.ts
@@ -0,0 +1,22 @@
+import { describe, it, expect } from '@jest/globals'
+import { responseSchema } from '../src/quest/response.js'
+
+describe('parsing response', () => {
+  it('should parse valid response', () => {
+    const response = {
+      type: 'narrative',
+      content: 'This is a response content',
+    }
+    const result = responseSchema.safeParse(response)
+    expect(result.error).toBeUndefined()
+  })
+
+  it('should fail to parse invalid response', () => {
+    const response = {
+      type: 'dialogue',
+      content: 'This is a response content',
+    }
+    const result = responseSchema.safeParse(response)
+    expect(result.error).toBeUndefined()
+  })
+})
diff --git a/packages/constants/tests/stage.test.ts b/packages/constants/tests/stage.test.ts
new file mode 100644
index 0000000..60b8297
--- /dev/null
+++ b/packages/constants/tests/stage.test.ts
@@ -0,0 +1,29 @@
+import { describe, it, expect } from '@jest/globals'
+import { stageSchema } from '../src/quest/stage.js'
+
+describe('parsing stage', () => {
+  it('should parse valid stage', () => {
+    const stage = {
+      id: 'start',
+      task: '按下 `開始` ����開始',
+      requirements: ['start'],
+      condition: {
+        command: ['^echo start$'],
+      },
+      responses: [
+        {
+          type: 'text',
+          content: `在畫面的中下方的區��是終端機，你可以在終端機��輸入指令來操作電��。
+  在終端機中，你所看到的 \`commander:~ $\` 叫做命令提示字串。
+  ��令提示字串最後的��字號 \`$\` 叫命令提示符，你必須將指令輸入在它的後方。
+  ��你輸入完指令並按下 Enter 之後，終端機會��行你輸入的指令，並且會從終端機的下一行開始輸出指令的��行結果。
+  直到你看到新的 \`commander:~ $\` 出現時，代表你可以輸入下一個指令了。
+  ��在請你輸入 \`echo hello\` 來看看會發生什麼事。`,
+        },
+      ],
+      hints: ['��  在 `commander:~ $` ��面輸入 `echo hello` ��按下 Enter'],
+    }
+    const result = stageSchema.safeParse(stage)
+    expect(result.error).toBeUndefined()
+  })
+})
diff --git a/server/src/cli/build.ts b/server/src/cli/build.ts
index 00e1906..86509e1 100644
--- a/server/src/cli/build.ts
+++ b/server/src/cli/build.ts
@@ -1,9 +1,9 @@
-import { getQuestDockerfiles } from '../utils/quest.js'
+import { questManager } from '../models/quest.js'
 import { buildQuestImage } from '../containers/docker.js'
 import logger from '../utils/logger.js'
 
 async function buildImages() {
-  const quests = await getQuestDockerfiles()
+  const quests = await questManager.getQuestDockerfiles()
   logger.info(`Building ${quests.length} images`)
   return Promise.all(
     quests.map(({ id, questPath }) => {
diff --git a/server/src/index.ts b/server/src/index.ts
index d287884..3ac09d0 100644
--- a/server/src/index.ts
+++ b/server/src/index.ts
@@ -10,7 +10,7 @@ import connectDB from '@linux-odyssey/models'
 import './auth/passport.js'
 import socketServer from './api/socket.js'
 import apiRouter from './api/routes/index.js'
-import { loadAndUpdateQuests } from './utils/quest.js'
+import { questManager } from './models/quest.js'
 import config from './config.js'
 import errorHandler from './middleware/error.js'
 import { globalRateLimit } from './middleware/rateLimiter.js'
@@ -42,7 +42,7 @@ async function main() {
   }
 
   try {
-    await loadAndUpdateQuests()
+    await questManager.loadAndUpdateQuests()
   } catch (err) {
     logger.error('Failed to load quests', err)
     return
diff --git a/server/src/models/quest.ts b/server/src/models/quest.ts
new file mode 100644
index 0000000..3a80250
--- /dev/null
+++ b/server/src/models/quest.ts
@@ -0,0 +1,102 @@
+/* eslint-disable max-classes-per-file */
+import fs from 'fs/promises'
+import path from 'path'
+import yaml from 'yaml'
+
+import { Quest, questSchema } from '@linux-odyssey/constants'
+import logger from '../utils/logger.js'
+
+class QuestValidationError extends Error {
+  questId: string
+  error: any
+
+  constructor(message: string, questId: string, error: any) {
+    super(message)
+    this.name = 'QuestValidationError'
+    this.questId = questId
+    this.error = error
+  }
+}
+
+class QuestManager {
+  private quests = new Map<string, Quest>()
+  private questDirectory = path.join(process.cwd(), '..', 'quests')
+
+  get(id: string) {
+    return this.quests.get(id)
+  }
+
+  getAll() {
+    return Array.from(this.quests.values())
+  }
+
+  private async mapQuests(callback: QuestCallback) {
+    const questNames = await fs.readdir(this.questDirectory, {
+      withFileTypes: true,
+    })
+
+    return Promise.all(
+      questNames
+        .filter(
+          (dirent) => dirent.isDirectory() && !dirent.name.startsWith('.')
+        )
+        .map((dirent) => {
+          const id = dirent.name
+          const questPath = path.join(this.questDirectory, id)
+          return callback(id, questPath)
+        })
+    )
+  }
+
+  private async loadGlobalExceptions() {
+    const exceptionsPath = path.join(this.questDirectory, 'exceptions.yml')
+    const body = await fs.readFile(exceptionsPath, 'utf-8')
+    return yaml.parse(body)
+  }
+
+  async loadAndUpdateQuests() {
+    const { exceptions } = await this.loadGlobalExceptions()
+    return this.mapQuests(async (id, questPath) => {
+      const files = await fs.readdir(questPath)
+      if (!files.includes('game.yml')) {
+        throw new QuestValidationError(`Missing game.yml`, id, null)
+      }
+
+      try {
+        const body = await fs.readFile(
+          path.join(questPath, 'game.yml'),
+          'utf-8'
+        )
+
+        const questData = yaml.parse(body, {
+          merge: true,
+        })
+
+        const image = files.includes('Dockerfile') ? id : 'base'
+        const quest = questSchema.parse({
+          _id: id,
+          image,
+          ...questData,
+        })
+        quest.exceptions.push(...exceptions)
+        this.quests.set(id, quest)
+      } catch (error) {
+        logger.error(`Error parsing quest`, { id, error })
+        throw new QuestValidationError(`Error parsing quest`, id, error)
+      }
+    })
+  }
+
+  async getQuestDockerfiles() {
+    const questlist = await this.mapQuests(async (id, questPath) => {
+      const files = await fs.readdir(questPath)
+      return files.includes('Dockerfile') ? { id, questPath } : null
+    })
+    return questlist.filter((quest) => quest !== null)
+  }
+}
+
+// eslint-disable-next-line no-unused-vars
+type QuestCallback = (id: string, questPath: string) => Promise<any>
+
+export const questManager = new QuestManager()
diff --git a/server/src/utils/quest.ts b/server/src/utils/quest.ts
deleted file mode 100644
index 9fda0b6..0000000
--- a/server/src/utils/quest.ts
+++ /dev/null
@@ -1,84 +0,0 @@
-import fs from 'fs/promises'
-import path from 'path'
-import yaml from 'yaml'
-
-import { Quest } from '@linux-odyssey/models'
-import logger from './logger.js'
-
-const questDirectory = path.join(process.cwd(), '..', 'quests')
-
-class QuestValidationError extends Error {
-  questId: string
-  error: any
-
-  constructor(message: string, questId: string, error: any) {
-    super(message)
-    this.name = 'QuestValidationError'
-    this.questId = questId
-    this.error = error
-  }
-}
-
-// eslint-disable-next-line no-unused-vars
-type QuestCallback = (id: string, questPath: string) => Promise<any>
-
-async function mapQuests(callback: QuestCallback) {
-  const questNames = await fs.readdir(questDirectory, {
-    withFileTypes: true,
-  })
-
-  return Promise.all(
-    questNames
-      .filter((dirent) => dirent.isDirectory() && !dirent.name.startsWith('.'))
-      .map((dirent) => {
-        const id = dirent.name
-        const questPath = path.join(questDirectory, id)
-        return callback(id, questPath)
-      })
-  )
-}
-
-async function loadGlobalExceptions() {
-  const exceptionsPath = path.join(questDirectory, 'exceptions.yml')
-  const body = await fs.readFile(exceptionsPath, 'utf-8')
-  return yaml.parse(body)
-}
-
-export async function loadAndUpdateQuests() {
-  await Quest.deleteMany({})
-  const { exceptions } = await loadGlobalExceptions()
-  return mapQuests(async (id, questPath) => {
-    const files = await fs.readdir(questPath)
-    if (!files.includes('game.yml')) {
-      throw new QuestValidationError(`Missing game.yml`, id, null)
-    }
-
-    try {
-      const body = await fs.readFile(path.join(questPath, 'game.yml'), 'utf-8')
-
-      const questData = yaml.parse(body, {
-        merge: true,
-      })
-
-      const image = files.includes('Dockerfile') ? id : 'base'
-      const quest = new Quest({
-        _id: id,
-        image,
-        ...questData,
-      })
-      quest.exceptions.push(...exceptions)
-      await quest.save()
-    } catch (error) {
-      logger.error(`Error parsing quest`, { id, error })
-      throw new QuestValidationError(`Error parsing quest`, id, error)
-    }
-  })
-}
-
-export async function getQuestDockerfiles() {
-  const quests = await mapQuests(async (id, questPath) => {
-    const files = await fs.readdir(questPath)
-    return files.includes('Dockerfile') ? { id, questPath } : null
-  })
-  return quests.filter((quest) => quest !== null)
-}