diff --git a/apps/api/src/routes/content.ts b/apps/api/src/routes/content.ts
index 5a23a00..635a549 100644
--- a/apps/api/src/routes/content.ts
+++ b/apps/api/src/routes/content.ts
@@ -1,4 +1,5 @@
 import {
+  announcementListItemSchema,
   announcementListSchema,
   announcementSchema,
   createMessageRequestSchema,
@@ -35,7 +36,7 @@ contentRoutes.get("/announcements", async (c) => {
       .orderBy(desc(schema.announcement.top), desc(schema.announcement.createTime)).limit(limit).offset(offset),
   ])
   return success(c, announcementListSchema.parse({
-    results: rows.map(({ announcement, user, realName }) => announcementSchema.parse({
+    results: rows.map(({ announcement, user, realName }) => announcementListItemSchema.parse({
       id: announcement.id,
       title: announcement.title,
       tag: announcement.tag,
diff --git a/apps/web/src/admin/announcement/list.vue b/apps/web/src/admin/announcement/list.vue
index 04ee8db..1984a38 100644
--- a/apps/web/src/admin/announcement/list.vue
+++ b/apps/web/src/admin/announcement/list.vue
@@ -2,7 +2,7 @@
 import { NSwitch } from "naive-ui"
 import Pagination from "shared/components/Pagination.vue"
 import { parseTime } from "utils/functions"
-import type { AnnouncementListItem } from "utils/types"
+import type { AdminAnnouncementListItem } from "utils/types"
 import { editAnnouncement, getAnnouncement, getAnnouncementList } from "../api"
 import Actions from "./components/Actions.vue"
 
@@ -12,9 +12,9 @@ const query = reactive({
   limit: 10,
   page: 1,
 })
-const announcements = ref<AnnouncementListItem[]>([])
+const announcements = ref<AdminAnnouncementListItem[]>([])
 
-const columns: DataTableColumn<AnnouncementListItem>[] = [
+const columns: DataTableColumn<AdminAnnouncementListItem>[] = [
   { title: "ID", key: "id", width: 60 },
   { title: "标题", key: "title", minWidth: 300 },
   { title: "标签", key: "tag", width: 80 },
@@ -64,7 +64,7 @@ const columns: DataTableColumn<AnnouncementListItem>[] = [
 
 // 列表响应不含 content（正文是 8MB 上限的富文本），而更新接口要求 content 必填 ——
 // 拿列表里那行直接回传会 400。所以先取回整条再改。
-async function toggleVisible(announcement: AnnouncementListItem) {
+async function toggleVisible(announcement: AdminAnnouncementListItem) {
   const next = !announcement.visible
   try {
     const full = await getAnnouncement(announcement.id)
diff --git a/apps/web/src/admin/api.ts b/apps/web/src/admin/api.ts
index b2e108a..42ee66f 100644
--- a/apps/web/src/admin/api.ts
+++ b/apps/web/src/admin/api.ts
@@ -21,16 +21,16 @@ import type {
   AdminProblem,
   AdminProblemList,
   AdminTag,
-  Announcement,
+  AdminAnnouncement,
   AnnouncementEdit,
-  AnnouncementListItem,
+  AdminAnnouncementListItem,
   BlankContest,
   BlankProblem,
   Contest,
   Exercise,
   ExerciseType,
   SqlDisplay,
-  TestcaseUploadedReturns,
+  UploadTestCaseResponse,
   Tutorial,
   User,
   WebsiteConfig,
@@ -225,7 +225,7 @@ export function uploadTestcases(file: File, options: { sql?: boolean } = {}) {
   if (options.sql) {
     form.append("sql", "1")
   }
-  return api.post<TestcaseUploadedReturns>("admin/test-cases", form, {
+  return api.post<UploadTestCaseResponse>("admin/test-cases", form, {
     headers: { "content-type": "multipart/form-data" },
   })
 }
@@ -371,14 +371,14 @@ export function deleteJudgeServer(hostname: string) {
 }
 
 export function getAnnouncementList(offset = 0, limit = 10) {
-  return api.get<{ results: AnnouncementListItem[]; total: number }>(
+  return api.get<{ results: AdminAnnouncementListItem[]; total: number }>(
     "admin/announcements",
     { params: { offset, limit } },
   )
 }
 
 export function getAnnouncement(id: number) {
-  return api.get<Announcement>(`admin/announcements/${id}`)
+  return api.get<AdminAnnouncement>(`admin/announcements/${id}`)
 }
 
 export function deleteAnnouncement(id: number) {
@@ -387,12 +387,12 @@ export function deleteAnnouncement(id: number) {
 
 export function editAnnouncement(announcement: AnnouncementEdit) {
   const { id, ...body } = announcement
-  return api.put<Announcement>(`admin/announcements/${id}`, body)
+  return api.put<AdminAnnouncement>(`admin/announcements/${id}`, body)
 }
 
 export function createAnnouncement(announcement: AnnouncementEdit) {
   const { id: _id, ...body } = announcement
-  return api.post<Announcement>("admin/announcements", body)
+  return api.post<AdminAnnouncement>("admin/announcements", body)
 }
 
 export function getTutorialList() {
diff --git a/apps/web/src/oj/announcement/list.vue b/apps/web/src/oj/announcement/list.vue
index 027dd29..156ae22 100644
--- a/apps/web/src/oj/announcement/list.vue
+++ b/apps/web/src/oj/announcement/list.vue
@@ -5,7 +5,7 @@ import Pagination from "shared/components/Pagination.vue"
 import { useBreakpoints } from "shared/composables/breakpoints"
 import { parseTime } from "utils/functions"
 import { renderTableTitle } from "utils/renders"
-import type { Announcement } from "utils/types"
+import type { AnnouncementListItem } from "utils/types"
 import TitleWithTag from "./components/TitleWithTag.vue"
 
 const total = ref(0)
@@ -19,7 +19,7 @@ const query = reactive({
   limit: 10,
   page: 1,
 })
-const columns: DataTableColumn<Announcement>[] = [
+const columns: DataTableColumn<AnnouncementListItem>[] = [
   {
     key: "title",
     title: renderTableTitle("公告标题", "streamline-emojis:fire"),
@@ -45,20 +45,20 @@ const columns: DataTableColumn<Announcement>[] = [
     width: 120,
   },
 ]
-function rowProps(row: Announcement) {
+function rowProps(row: AnnouncementListItem) {
   return {
     style: "cursor: pointer",
     onclick: () => showContent(row),
   }
 }
 
-async function showContent(announcement: Announcement) {
+async function showContent(announcement: AnnouncementListItem) {
   const res = await getAnnouncement(announcement.id)
   toggleShow(true)
   title.value = announcement.title
   content.value = res.content
 }
-const announcements = ref<Announcement[]>([])
+const announcements = ref<AnnouncementListItem[]>([])
 
 async function listAnnouncements() {
   const offset = (query.page - 1) * query.limit
diff --git a/apps/web/src/oj/api.ts b/apps/web/src/oj/api.ts
index 57a0039..9a9d003 100644
--- a/apps/web/src/oj/api.ts
+++ b/apps/web/src/oj/api.ts
@@ -41,6 +41,7 @@ import api from "utils/api"
 import { filterResult } from "oj/transforms"
 import type {
   Announcement,
+  AnnouncementListItem,
   ContestRank,
   Profile,
   Message,
@@ -260,7 +261,7 @@ export function updateProfile(data: { realName: string; mood: string }) {
 }
 
 export function getAnnouncementList(offset = 0, limit = 10) {
-  return api.get<{ results: Announcement[]; total: number }>("announcements", {
+  return api.get<{ results: AnnouncementListItem[]; total: number }>("announcements", {
     params: { limit, offset },
   })
 }
diff --git a/apps/web/src/oj/problem/composables/useSubmissionMonitor.ts b/apps/web/src/oj/problem/composables/useSubmissionMonitor.ts
index 3ff5632..ca523a6 100644
--- a/apps/web/src/oj/problem/composables/useSubmissionMonitor.ts
+++ b/apps/web/src/oj/problem/composables/useSubmissionMonitor.ts
@@ -106,7 +106,7 @@ export function useSubmissionMonitor() {
         submission.value &&
         (submission.value.result === SubmissionStatus.judging ||
           submission.value.result === SubmissionStatus.pending ||
-          submission.value.result === 9) // 9 = submitting
+          submission.value.result === SubmissionStatus.submitting)
       ) {
         console.log("[SubmissionMonitor] WebSocket未及时响应，启动轮询保底")
         resumePolling()
@@ -119,7 +119,7 @@ export function useSubmissionMonitor() {
   // ==================== 启动监控 ====================
   const startMonitoring = (id: string) => {
     submissionId.value = id
-    submission.value = { id, result: 9 } as Submission // 9 = submitting
+    submission.value = { id, result: SubmissionStatus.submitting } as Submission
 
     // 取消之前的断开计划
     cancelScheduledDisconnect()
diff --git a/apps/web/src/utils/types.ts b/apps/web/src/utils/types.ts
index 725d2df..6685452 100644
--- a/apps/web/src/utils/types.ts
+++ b/apps/web/src/utils/types.ts
@@ -12,6 +12,8 @@ import type {
   Grade,
   ProblemDetail,
   ProblemDifficulty,
+  JudgeStatus,
+  CreateAnnouncementRequest,
 } from "@oj2/contract"
 
 /**
@@ -64,8 +66,15 @@ export type {
   SqlDisplayColumn,
 } from "@oj2/contract"
 
-export type SUBMISSION_RESULT =
-  -2 | -1 | 0 | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10
+/**
+ * 判题状态码 + 前端本地的「正在提交」(9)。
+ *
+ * 后端那 11 个码**从契约派生**，不再手抄 —— judgeStatusSchema 加一个码，
+ * constants.ts 的 JUDGE_STATUS 会因为缺映射当场编译不过，这正是
+ * CLAUDE.md 说的「三处同步」想要的效果。9 是后端永远不会下发的伪状态，
+ * 见 constants.ts 的 SubmissionStatus.submitting。
+ */
+export type SUBMISSION_RESULT = JudgeStatus | 9
 
 export type ProblemStatus = "passed" | "failed" | "not_test"
 
@@ -89,7 +98,7 @@ export type {
  * （stripped_output_md5 / input_size / output_size）。这套键名保持 snake_case
  * 是因为它会原样落进 problem.test_case_score 和判题沙箱读的 info 文件。
  */
-export type { UploadTestCaseResponse as TestcaseUploadedReturns } from "@oj2/contract"
+export type { UploadTestCaseResponse } from "@oj2/contract"
 
 /**
  * 题目表单里的测试点：上传返回的条目 + 前端本地算出的分值。
@@ -408,23 +417,21 @@ export type {
   AcTrend,
 } from "@oj2/contract"
 
-export interface AnnouncementEdit {
-  id: number
-  title: string
-  tag: string
-  content: string
-  visible: boolean
-  top: boolean
-}
+/**
+ * 公告。两侧形状**不同**，原来这里只手抄了后台那份、oj 侧也拿它当类型用：
+ * oj 的 `/announcements` 列表既不下发 `content` 也不下发 `visible`
+ * （见 apps/api/src/routes/content.ts），于是类型声称有、实际是 undefined。
+ * 现在各取各的契约类型。
+ */
+export type {
+  Announcement,
+  AnnouncementListItem,
+  AdminAnnouncement,
+  AdminAnnouncementListItem,
+} from "@oj2/contract"
 
-export interface Announcement extends AnnouncementEdit {
-  createdBy: SampleUser
-  createTime: string
-  lastUpdateTime: string
-}
-
-/** 列表不下发正文：公告是 8MB 上限的富文本，列表页只显示标题 */
-export type AnnouncementListItem = Omit<Announcement, "content">
+/** 后台编辑表单：请求体 + id（新建时填 0，提交前由 api 层剥掉） */
+export type AnnouncementEdit = CreateAnnouncementRequest & { id: number }
 
 /**
  * 站内信。取契约的形状，只把 `submission` 换成前端窄化过的那个
@@ -445,7 +452,7 @@ export type {
   ReactionCounts,
   ReactionState,
 } from "@oj2/contract"
-import type { ReactionKey, SampleUser } from "@oj2/contract"
+import type { ReactionKey } from "@oj2/contract"
 
 /**
  * 教程。直接取契约 —— 手抄的那份把 `createdBy` 写成了可选的 `User`（后端下发的是
diff --git a/packages/contract/src/admin.ts b/packages/contract/src/admin.ts
index 060f8f3..3a9a105 100644
--- a/packages/contract/src/admin.ts
+++ b/packages/contract/src/admin.ts
@@ -24,9 +24,13 @@ export const adminAnnouncementSchema = z.object({
   lastUpdateTime: z.string(),
 })
 
+// 列表不带 content：公告正文是 8MB 上限的富文本，列表页只显示标题
+export const adminAnnouncementListItemSchema = adminAnnouncementSchema.omit({
+  content: true,
+})
+
 export const adminAnnouncementListSchema = paginatedSchema(
-  // 列表不带 content：公告正文是 8MB 上限的富文本，列表页只显示标题
-  adminAnnouncementSchema.omit({ content: true }),
+  adminAnnouncementListItemSchema,
 )
 
 export const createAnnouncementRequestSchema = z.object({
@@ -40,6 +44,9 @@ export const createAnnouncementRequestSchema = z.object({
 export const updateAnnouncementRequestSchema = createAnnouncementRequestSchema
 
 export type AdminAnnouncement = z.infer<typeof adminAnnouncementSchema>
+export type AdminAnnouncementListItem = z.infer<
+  typeof adminAnnouncementListItemSchema
+>
 
 // ---------------------------------------------------------------- 教程 / 练习
 
diff --git a/packages/contract/src/content.ts b/packages/contract/src/content.ts
index 899803f..8cb098c 100644
--- a/packages/contract/src/content.ts
+++ b/packages/contract/src/content.ts
@@ -7,14 +7,26 @@ export const announcementSchema = z.object({
   id: z.number().int(),
   title: z.string(),
   tag: z.string(),
-  content: z.string().optional(),
+  content: z.string(),
   top: z.boolean(),
   createdBy: sampleUserSchema,
   createTime: z.string(),
   lastUpdateTime: z.string(),
 })
 
-export const announcementListSchema = paginatedSchema(announcementSchema)
+/**
+ * 列表不下发正文：公告是 8MB 上限的富文本，列表页只显示标题。
+ * 原来 content 写成 `.optional()` 让一个 schema 兼两种形态，结果详情页
+ * 拿到的 content 类型上也是 `string | undefined`，组件只能 ?? 兜底。
+ * 与后台侧 adminAnnouncementListItemSchema 同一个套路。
+ */
+export const announcementListItemSchema = announcementSchema.omit({
+  content: true,
+})
+
+export const announcementListSchema = paginatedSchema(
+  announcementListItemSchema,
+)
 
 export const messageSchema = z.object({
   id: z.number().int(),
@@ -76,6 +88,7 @@ export const exerciseSchema = z.object({
 export type Message = z.infer<typeof messageSchema>
 export type MessageList = z.infer<typeof messageListSchema>
 export type Announcement = z.infer<typeof announcementSchema>
+export type AnnouncementListItem = z.infer<typeof announcementListItemSchema>
 export type TutorialSummary = z.infer<typeof tutorialSummarySchema>
 
 export type AnnouncementList = z.infer<typeof announcementListSchema>