diff --git a/src/main/index.ts b/src/main/index.ts
index a56f313..9a51f66 100644
--- a/src/main/index.ts
+++ b/src/main/index.ts
@@ -150,6 +150,8 @@ function nextGetMessagesRequestId(): string {
 import type { AppLogEntry } from '../shared/app-log'
 import { appUpdateService } from './services/app-update-service'
 import { clearCache, getCacheSummary, openKnowledgeDirectory } from './services/cache-service'
+import { imageTextIndexService } from './services/image-text-index-service'
+import type { ImageTextIndexStartOptions } from '../shared/image-text-index'
 import type { CacheClearScope } from './services/cache-service'
 import { configureRecallArchive, RecallArchiveMonitor } from './services/recall-archive-service'
 import { VideoAssetService } from './video-asset-service'
@@ -637,8 +639,94 @@ app.whenReady().then(async () => {
   voiceRecognition.onTranscriptUpdate((update) =>
     knowledgeSearchService?.indexVoiceTranscript(update)
   )
+
+  /**
+   * 确保图片解密服务可用（按需创建，与 `db:getImage` 冷路径同一套构造方式）。
+   *
+   * 提取成显式入口是因为原来它只存在于 `db:getImage` 的闭包里，
+   * 别的需要解密的路径（图片文字索引回填）拿不到、只能拿到 `null`。
+   */
+  function ensureImageDecryptService(): ImageDecryptService | null {
+    if (imageDecryptService) return imageDecryptService
+    const { xorKey, aesKey } = getConfiguredImageKeys()
+    if (!aesKey) return null
+    imageDecryptService = new ImageDecryptService(
+      xorKey,
+      aesKey,
+      chat.getChatDb()?.getWcdb4Client(),
+      loadSettings().dbRoot
+    )
+    return imageDecryptService
+  }
+
+  // 图片文字索引（本地 System OCR 派生文本）。
+  // 与语音转写完全同构：派生文本在 main 进程解析后贴到消息上，Knowledge 侧只消费结果。
+  knowledgeSearchService.setImageOcrResolver((conversationId, messageId) =>
+    imageTextIndexService.getConversationOcr(conversationId).get(messageId)
+  )
+  /**
+   * 图片文字索引需要解密图片。
+   *
+   * 原先这个依赖直接读 `imageDecryptService`，而它**只在 `db:getImage`（用户点开某张图）
+   * 里才懒加载** —— 于是全量回填在用户没点开过任何图片时拿到 `null`，
+   * 45,479 张图片全部被记成 `decrypt_failed`（见事故报告）。
+   * 这里改成显式的"按需确保"，凡是需要解密的路径都能自己把它建起来。
+   */
+  imageTextIndexService.bind({
+    databaseRoot: join(app.getPath('userData'), 'image-text-index'),
+    resolveAccountId: () =>
+      chat.isReady()
+        ? String(chat.getSelfAccountInfo()?.wxid || chat.getCurrentAccountRoot() || '')
+        : '',
+    resolveAccountRoot: () => chat.getCurrentAccountRoot() || loadSettings().dbRoot || '',
+    listContacts: async () => {
+      const contacts = await chat.listContactsAsync()
+      return contacts.map((contact) => ({
+        md5: contact.md5,
+        m_nsUsrName: contact.m_nsUsrName,
+        type: contact.type
+      }))
+    },
+    listMessages: (conversationId) => chat.listMessagesAsync(conversationId),
+    countConversationImages: (conversationId, sinceMs) =>
+      chat.countImageMessagesAsync(conversationId, sinceMs),
+    imageWatermark: (conversationId, sinceMs) =>
+      chat.imageConversationWatermarkAsync(conversationId, sinceMs),
+    decryptService: () => ensureImageDecryptService(),
+    capability: () => systemOcrService.getCapability(),
+    recognize: async (imageDataUrl) => {
+      const result = await systemOcrService.recognize({ imageDataUrl })
+      return {
+        success: result.success,
+        text: result.text,
+        language: result.language,
+        ...(result.errorCode ? { errorCode: result.errorCode } : {})
+      }
+    },
+    // 会话图片全部处理完 → 重建该会话索引，OCR 文本才可被 search_messages 检索。
+    onConversationIndexed: (conversationId) =>
+      knowledgeSearchService?.indexImageOcr(conversationId) ?? Promise.resolve()
+  })
   aiSearchPipelineService = new AiSearchPipelineService(knowledgeSearchService, aiProviderService)
   localQueryApiService = new LocalQueryApiService(knowledgeSearchService)
+  // 图片文字索引覆盖度是**独立覆盖维度**：接到 search_messages 的 tool result 上，
+  // 让 Query Agent 在图片索引没做完时不能凭 0 条证据断言"没有"。
+  localQueryApiService.setImageTextCoverageProvider(() =>
+    imageTextIndexService.getCoverageSnapshot()
+  )
+  /**
+   * 单条图片消息的 OCR 派生文本也要接到精确读消息路径上。
+   *
+   * 与覆盖度是**两件不同的事**：覆盖度回答"索引建了多少"，这里回答
+   * "这一条图片已经识别出的文字是什么"。只接前者的话，图片索引建好了模型也读不到正文，
+   * 只能看到一个空的 `attachment` —— 真机上就是这么把"图片里有 ChatGPT 价格"
+   * 答成"没有取得 OCR 文字"的。
+   *
+   * 只读派生库，**不触发 OCR / 解密 / 读原图**。
+   */
+  localQueryApiService.setImageOcrEntryProvider((conversationId, messageId) =>
+    imageTextIndexService.getConversationOcr(conversationId).get(messageId)
+  )
   setLocalQueryApiService(localQueryApiService)
   // Query Agent：生产 Runtime 只在这里实例化一次，桌面问问微信与 Agent Hub 共用同一个实例。
   queryAgentService = new QueryAgentService(
@@ -660,6 +748,11 @@ app.whenReady().then(async () => {
       if (!window.isDestroyed()) window.webContents.send('knowledge:status', status)
     }
   })
+  imageTextIndexService.onStatusChange((status) => {
+    for (const window of BrowserWindow.getAllWindows()) {
+      if (!window.isDestroyed()) window.webContents.send('image-text-index:status', status)
+    }
+  })
   voiceRecognition.modelManager.setProgressListener((status) => {
     for (const window of BrowserWindow.getAllWindows()) {
       if (!window.isDestroyed()) window.webContents.send('voice:modelProgress', status)
@@ -748,12 +841,25 @@ app.whenReady().then(async () => {
   ipcMain.handle('cache:getSummary', () => getCacheSummary())
   ipcMain.handle('cache:openKnowledgeDirectory', () => openKnowledgeDirectory())
   ipcMain.handle('cache:clear', async (_, scope: CacheClearScope) => {
-    const allowedScopes: CacheClearScope[] = ['bootstrap', 'electron', 'knowledge', 'all']
+    const allowedScopes: CacheClearScope[] = [
+      'bootstrap',
+      'electron',
+      'knowledge',
+      'image-text-index',
+      'all'
+    ]
     if (!allowedScopes.includes(scope)) return getCacheSummary()
     imageDecryptService = null
+    // 这里刻意**不再**提前 resetAccount()：清理钩子需要先读到派生库里的
+    // "哪些会话有 OCR 派生文本"，才能把这些会话的 Knowledge 索引一起失效。
+    // 句柄由 beforeClearImageTextIndex 内部的 clear() 自己关闭（删文件前）。
     return clearCache(scope, {
       beforeClearKnowledge: () =>
-        knowledgeSearchService?.prepareForCacheClear() || Promise.resolve()
+        knowledgeSearchService?.prepareForCacheClear() || Promise.resolve(),
+      beforeClearImageTextIndex: async () => {
+        await imageTextIndexService.prepareForCacheClear()
+        imageTextIndexService.resetAccount()
+      }
     })
   })
 
@@ -841,6 +947,8 @@ app.whenReady().then(async () => {
             .catch((error) => console.warn('[WCDB4] message cursor warmup failed:', error))
         }
         imageDecryptService = null
+        // 派生库按 accountId 分目录，切账号必须换句柄，否则会串账号。
+        imageTextIndexService.resetAccount()
         console.log(
           `[WCDB4] db:init ready sessions=${sessions.length} monitoring=${monitoring} cost=${Date.now() - startedAt}ms`
         )
@@ -1020,6 +1128,8 @@ app.whenReady().then(async () => {
       aesKey: result.aesKey
     })
     if (saved.success) imageDecryptService = null
+ // 派生库按 accountId 分目录，切账号必须换句柄，否则会串账号。
+ imageTextIndexService.resetAccount()
     return {
       ...result,
       success: saved.success,
@@ -1040,6 +1150,8 @@ app.whenReady().then(async () => {
   ipcMain.handle('image:saveConfig', (_, request: SaveImageKeyRequest) => {
     const result = imageKeyConfigService.save(request)
     if (result.success) imageDecryptService = null
+ // 派生库按 accountId 分目录，切账号必须换句柄，否则会串账号。
+ imageTextIndexService.resetAccount()
     return result
   })
 
@@ -1050,6 +1162,8 @@ app.whenReady().then(async () => {
   ipcMain.handle('image:clearConfig', () => {
     const result = imageKeyConfigService.clear()
     if (result.success) imageDecryptService = null
+ // 派生库按 accountId 分目录，切账号必须换句柄，否则会串账号。
+ imageTextIndexService.resetAccount()
     return result
   })
 
@@ -1338,6 +1452,32 @@ app.whenReady().then(async () => {
     if (!knowledgeSearchService) throw new Error('本地知识库服务尚未初始化')
     return knowledgeSearchService.cancelCurrentAccountIndex()
   })
+  // ---- 图片文字索引（本地 System OCR 派生文本，非 AI Provider）----
+  ipcMain.handle('image-text-index:getStatus', () => imageTextIndexService.getStatus())
+  /**
+   * 点击索引前的快速统计：纯 SQL COUNT，**不解密任何图片**。
+   * 这是「先告诉用户有多少张图片再决定是否开始」能足够快的前提。
+   */
+  ipcMain.handle('image-text-index:count', (_, sinceMs?: number) =>
+    imageTextIndexService.countImageMessages(sinceMs)
+  )
+  ipcMain.handle(
+    'image-text-index:start',
+    (_, options?: ImageTextIndexStartOptions) => imageTextIndexService.startPass(options ?? {})
+  )
+  ipcMain.handle('image-text-index:pause', () => imageTextIndexService.pause())
+  ipcMain.handle(
+    'image-text-index:resume',
+    (_, options?: ImageTextIndexStartOptions) => imageTextIndexService.resume(options ?? {})
+  )
+  ipcMain.handle('image-text-index:cancel', () => imageTextIndexService.cancel())
+  ipcMain.handle('image-text-index:clear', () => imageTextIndexService.clear())
+  // 只重置失败记录（成功记录与其它数据一律不动），供"修好代码后重跑"使用。
+  ipcMain.handle('image-text-index:resetFailures', () =>
+    imageTextIndexService.resetRetriableFailures()
+  )
+  // 派生索引修复：只重建 Knowledge 里的图片派生条目（L3），**不重新 OCR**（L1 不动）。
+  ipcMain.handle('image-text-index:repair', () => imageTextIndexService.repairKnowledgeIndex())
   ipcMain.handle('ai-search:run', (event, request: AiSearchPipelineRequest) => {
     if (!aiSearchPipelineService) throw new Error('本地搜索服务尚未初始化')
     return aiSearchPipelineService.run(request, (progress) => {
@@ -1963,6 +2103,8 @@ app.whenReady().then(async () => {
       if (aesKey) imageKeyConfigService.save({ resourceRoot, xorKey, aesKey })
       else imageKeyConfigService.clear()
       imageDecryptService = null
+      // 派生库按 accountId 分目录，切账号必须换句柄，否则会串账号。
+      imageTextIndexService.resetAccount()
     }
     if ('recallProtectionEnabled' in patch && chat.isReady()) {
       const currentDb = chat.getChatDb()
diff --git a/src/main/knowledge/knowledge-search-service.ts b/src/main/knowledge/knowledge-search-service.ts
index ced5755..7514bea 100644
--- a/src/main/knowledge/knowledge-search-service.ts
+++ b/src/main/knowledge/knowledge-search-service.ts
@@ -1,6 +1,7 @@
 import { monitorEventLoopDelay } from 'perf_hooks'
 import * as chat from '../services/chat-service'
 import type {
+  KnowledgeImageOcrState,
   KnowledgeAttachmentMetadata,
   KnowledgeEvidence,
   KnowledgeMessageKind,
@@ -24,6 +25,7 @@ import {
   emptyKnowledgeSearchTimings
 } from '../../shared/knowledge'
 import { KnowledgeService } from './knowledge-service'
+import { sourceMessageId } from './message-identity'
 import {
   voiceAccountIdentity,
   voiceMessageIdentity
@@ -118,11 +120,6 @@ function groupMemberDisplayName(member: chat.GroupSnapshot['members'][number]):
   )
 }
 
-function sourceMessageId(message: chat.FormattedMessage): string {
-  if (message.localId) return `local:${message.localId}`
-  if (message.id) return String(message.id)
-  return `${message.createTime || 0}:${message.serverId || message.content}`
-}
 
 function sourceKind(message: chat.FormattedMessage): KnowledgeMessageKind {
   if (message.voiceTranscript || message.type === '语音') return 'voice'
@@ -130,6 +127,16 @@ function sourceKind(message: chat.FormattedMessage): KnowledgeMessageKind {
     return message.exportMediaType
   }
   if (message.exportMediaType === 'file') return 'file'
+  // 索引路径上 `exportMediaType` **不会被赋值**（只有 export-service 会设它），
+  // 所以图片/视频/表情包必须从 contentData.type 判定，否则图片会静默落成 'other'，
+  // 进而让"图片文字索引"的 Evidence 丢掉真正的来源类型。
+  if (
+    message.contentData?.type === 'image' ||
+    message.contentData?.type === 'video' ||
+    message.contentData?.type === 'sticker'
+  ) {
+    return message.contentData.type
+  }
   if (message.contentData?.type === 'share' || message.contentData?.type === 'miniProgram') {
     return message.contentData.type === 'share' && message.contentData.typeVal === '6'
       ? 'file'
@@ -201,12 +208,16 @@ function toSourceMessage(
   accountId: string,
   conversationId: string,
   message: chat.FormattedMessage,
-  transcriptOverride?: string
+  transcriptOverride?: string,
+  imageOcr?: { state: KnowledgeImageOcrState; text: string }
 ): KnowledgeSourceMessage | null {
   if (!message.createTime) return null
   const extracted = sourceTextAndAttachment(message)
   const voiceTranscript = transcriptOverride?.trim() || message.voiceTranscript?.trim() || undefined
-  if (!extracted.text && !extracted.attachment && !voiceTranscript) return null
+  // 图片 OCR 文本走与语音转写完全相同的派生通道：有文本才入库，
+  // 没有文字的图片（表情包/风景）不会污染索引。
+  const imageOcrText = imageOcr?.text?.trim() || undefined
+  if (!extracted.text && !extracted.attachment && !voiceTranscript && !imageOcrText) return null
   return {
     accountId,
     conversationId,
@@ -218,7 +229,9 @@ function toSourceMessage(
     kind: sourceKind(message),
     text: extracted.text,
     attachment: extracted.attachment,
-    voiceTranscript
+    voiceTranscript,
+    ...(imageOcrText ? { imageOcrText } : {}),
+    ...(imageOcrText && imageOcr?.state ? { imageOcrState: imageOcr.state } : {})
   }
 }
 
@@ -256,6 +269,14 @@ export class KnowledgeSearchService {
   private interactiveIdleResolve: (() => void) | null = null
   private wcdbQueueMsTotal = 0
   private wcdbExecutionMsTotal = 0
+  /**
+   * 图片 OCR 文本解析器（由 main 注入）。
+   *
+   * 与语音同构：派生文本在**主进程**解析后贴到消息上，派生库不进 worker。
+   */
+  private imageOcrResolver:
+    | ((conversationId: string, messageId: string) => { state: KnowledgeImageOcrState; text: string } | undefined)
+    | undefined
   private voiceTranscriptResolver:
     | ((reference: VoiceMessageReference) => VoiceTranscriptSnapshot)
     | undefined
@@ -372,6 +393,15 @@ export class KnowledgeSearchService {
     this.voiceTranscriptResolver = resolver
   }
 
+  /** 注入图片 OCR 文本解析器（本地 System OCR 的派生结果）。 */
+  setImageOcrResolver(
+    resolver:
+      | ((conversationId: string, messageId: string) => { state: KnowledgeImageOcrState; text: string } | undefined)
+      | undefined
+  ): void {
+    this.imageOcrResolver = resolver
+  }
+
   /**
    * A successful recognition updates its source conversation. Consecutive
    * updates for the same conversation are coalesced because a complete
@@ -1074,8 +1104,16 @@ export class KnowledgeSearchService {
     const reference = this.voiceReferenceFromMessage(message)
     const snapshot = reference ? this.voiceTranscriptResolver?.(reference) : undefined
     const hydrated = this.withVoiceTranscript(message)
-    const source = toSourceMessage(accountId, conversationId, hydrated, transcriptOverride)
-    if (!source || source.kind !== 'voice') return source
+    const imageOcr = this.imageOcrResolver?.(conversationId, sourceMessageId(message))
+    const source = toSourceMessage(
+      accountId,
+      conversationId,
+      hydrated,
+      transcriptOverride,
+      imageOcr
+    )
+    if (!source) return source
+    if (source.kind !== 'image' && source.kind !== 'voice') return source
     return {
       ...source,
       voiceTranscriptState:
@@ -1105,6 +1143,38 @@ export class KnowledgeSearchService {
     }
   }
 
+  /**
+   * 某个会话的图片 OCR 处理完成 → 重建该会话的索引。
+   *
+   * 与"语音转写完成后单会话重索引"完全同构：整会话重读 + completeSnapshot 重建，
+   * 让 OCR 派生文本进入 chunks/FTS，从而可被 search_messages 检索。
+   * 原图片消息仍然是 authoritative source —— 这里只是让它多了一段派生文本，
+   * 不产生任何"OCR 消息"。
+   */
+  async indexImageOcr(conversationId: string): Promise<void> {
+    if (!chat.isReady()) return
+    const accountId = this.currentAccountId()
+    if (!accountId) return
+    const activeIndex = this.indexing.get(accountId)
+    if (activeIndex) await activeIndex
+    const contacts = await this.listContacts()
+    const contact = contacts.find((item) => item.md5 === conversationId)
+    if (!contact) return
+    const messages = await this.listMessages(contact.md5, undefined, undefined, 'background')
+    const sourceMessages = messages
+      .map((message) => this.toSourceMessage(accountId, contact.md5, message))
+      .filter((message): message is KnowledgeSourceMessage => Boolean(message))
+    await this.service.index({
+      accountId,
+      conversations: [
+        { conversationId: contact.md5, completeSnapshot: true, messages: sourceMessages }
+      ],
+      chunker: DEFAULT_KNOWLEDGE_CHUNKER,
+      fts: DEFAULT_KNOWLEDGE_FTS_CONFIG
+    })
+    await this.refreshStatus(accountId)
+  }
+
   private async indexVoiceTranscriptNow(update: VoiceTranscriptUpdate): Promise<void> {
     if (!chat.isReady()) return
     if (update.state === 'transcribed' && !update.transcript?.trim()) return
diff --git a/src/main/knowledge/knowledge-store.ts b/src/main/knowledge/knowledge-store.ts
index 9f24b85..1c283f8 100644
--- a/src/main/knowledge/knowledge-store.ts
+++ b/src/main/knowledge/knowledge-store.ts
@@ -19,7 +19,11 @@ import type {
   KnowledgeSearchTimings,
   KnowledgeSearchResult
 } from '../../shared/knowledge'
-import { emptyKnowledgeSearchTimings, KNOWLEDGE_SCHEMA_VERSION } from '../../shared/knowledge'
+import {
+  emptyKnowledgeSearchTimings,
+  KNOWLEDGE_SCHEMA_VERSION,
+  toEvidenceDisplayText
+} from '../../shared/knowledge'
 import { chunkConversation } from './chunker'
 import { normalizeKnowledgeMessage } from './normalizer'
 
@@ -789,7 +793,11 @@ export class KnowledgeStore {
       timestamp: Number(row.create_time),
       messageIds: chunk ? chunk.map((item) => String(item.message_id)) : [messageId],
       sourceKind: String(row.kind) as KnowledgeEvidence['sourceKind'],
-      text: String(row.searchable_text),
+      // 内部前缀（`图片文字：`）绝不能进 Evidence：面向用户与模型的是可读文本，
+      // 来源信息由下面的结构化字段表达。
+      text: toEvidenceDisplayText(String(row.searchable_text)),
+      ...(row.image_ocr_text ? { imageOcrText: String(row.image_ocr_text) } : {}),
+      ...(row.image_ocr_text ? { derivedSource: 'image_ocr' as const } : {}),
       score: String(row.kind) === 'system' ? 1 : 0
     }
   }
@@ -899,6 +907,7 @@ export class KnowledgeStore {
         attachment_json TEXT,
         voice_transcript TEXT,
         voice_transcript_state TEXT,
+        image_ocr_text TEXT,
         PRIMARY KEY (conversation_id, message_id)
       ) STRICT;
       CREATE INDEX IF NOT EXISTS knowledge_messages_conversation_time
@@ -957,6 +966,14 @@ export class KnowledgeStore {
     if (!messageColumns.has('voice_transcript_state')) {
       this.database.exec('ALTER TABLE knowledge_messages ADD COLUMN voice_transcript_state TEXT')
     }
+    // 图片 OCR 派生文本单独留一列（不只是埋进 searchable_text）。
+    //
+    // 为什么必须落列而不是从 searchable_text 里截字符串：Evidence 需要回答
+    // "这条结果是不是来自图片里的文字"，并按此给出来源标记与 OCR 片段。
+    // 靠解析前缀来判来源，一旦前缀格式调整就会静默失效。
+    if (!messageColumns.has('image_ocr_text')) {
+      this.database.exec('ALTER TABLE knowledge_messages ADD COLUMN image_ocr_text TEXT')
+    }
     this.writeMetaIfMissing('schema_version', String(KNOWLEDGE_SCHEMA_VERSION))
     const storedAccount = this.readMeta('account_id')
     if (storedAccount && storedAccount !== this.accountId) {
@@ -1137,8 +1154,9 @@ export class KnowledgeStore {
     const upsert = this.database.prepare(
       `INSERT INTO knowledge_messages (
         account_id, conversation_id, message_id, create_time, content_hash, searchable_text,
-        kind, sender_id, sender_name, attachment_json, voice_transcript, voice_transcript_state
-      ) VALUES (?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?)
+        kind, sender_id, sender_name, attachment_json, voice_transcript, voice_transcript_state,
+        image_ocr_text
+      ) VALUES (?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?)
       ON CONFLICT(conversation_id, message_id) DO UPDATE SET
         create_time = excluded.create_time,
         content_hash = excluded.content_hash,
@@ -1148,7 +1166,8 @@ export class KnowledgeStore {
         sender_name = excluded.sender_name,
         attachment_json = excluded.attachment_json,
         voice_transcript = excluded.voice_transcript,
-        voice_transcript_state = excluded.voice_transcript_state`
+        voice_transcript_state = excluded.voice_transcript_state,
+        image_ocr_text = excluded.image_ocr_text`
     )
     for (let index = 0; index < messages.length; index += 1) {
       this.assertNotAborted(signal)
@@ -1165,7 +1184,8 @@ export class KnowledgeStore {
         message.senderName ?? null,
         message.attachment ? encodedJson(message.attachment) : null,
         message.voiceTranscript ?? null,
-        message.voiceTranscriptState ?? null
+        message.voiceTranscriptState ?? null,
+        message.imageOcrText ?? null
       )
       if (index % YIELD_EVERY === 0) {
         onProgress(index + 1, 0)
diff --git a/src/main/knowledge/message-identity.ts b/src/main/knowledge/message-identity.ts
new file mode 100644
index 0000000..a715d65
--- /dev/null
+++ b/src/main/knowledge/message-identity.ts
@@ -0,0 +1,24 @@
+/**
+ * 消息身份的**唯一真源**。
+ *
+ * 这个规则同时被三处需要：
+ * - Knowledge 索引写入 `knowledge_messages.message_id`
+ * - 图片文字索引的 binding（必须与 Knowledge 里的 message_id 完全一致，否则 OCR 文本贴不到消息上）
+ * - Evidence → 档案跳转的 messageRef
+ *
+ * 任何一处各自复制一份，都会在 `local:` 前缀上静默失配（项目里已经有这个坑的历史注释），
+ * 所以抽成一个模块，谁都不许再抄。
+ */
+import type * as chat from '../services/chat-service'
+
+/**
+ * 源消息 → 稳定消息 id。
+ *
+ * 降级顺序刻意保守：`localId` 是 WCDB 行内最稳的本地 id；其次用消息自带 id；
+ * 最后才退化成「时间 + 服务端 id / 内容」的组合（仅在极端缺字段时命中）。
+ */
+export function sourceMessageId(message: chat.FormattedMessage): string {
+  if (message.localId) return `local:${message.localId}`
+  if (message.id) return String(message.id)
+  return `${message.createTime || 0}:${message.serverId || message.content}`
+}
diff --git a/src/main/knowledge/normalizer.ts b/src/main/knowledge/normalizer.ts
index 799cfba..213a16e 100644
--- a/src/main/knowledge/normalizer.ts
+++ b/src/main/knowledge/normalizer.ts
@@ -24,6 +24,10 @@ export function normalizeKnowledgeMessage(
   const transcript = compact(source.voiceTranscript)
   if (transcript) sections.push(`语音转写：${transcript}`)
 
+  // 图片 OCR 文本：与语音同样的"固定前缀"约定，让检索与展示都能识别这是派生内容。
+  const imageText = compact(source.imageOcrText)
+  if (imageText) sections.push(`图片文字：${imageText}`)
+
   const attachmentName = compact(source.attachment?.name)
   if (attachmentName) {
     const label = source.attachment?.kind === 'link' ? '链接' : '附件'
@@ -45,6 +49,7 @@ export function normalizeKnowledgeMessage(
         senderId: source.senderId || '',
         kind: source.kind,
         voiceTranscriptState: source.voiceTranscriptState || '',
+        imageOcrState: source.imageOcrState || '',
         searchableText
       })
     )
diff --git a/src/main/services/ask-wechat-service.ts b/src/main/services/ask-wechat-service.ts
index 9b361cb..f7909ce 100644
--- a/src/main/services/ask-wechat-service.ts
+++ b/src/main/services/ask-wechat-service.ts
@@ -86,7 +86,8 @@ export class AskWechatService {
       const diagnostics = this.diagnostics(
         { provider: '', model: '', modelCallCount: 0, toolCallCount: 0, traces: [] },
         startedAt,
-        'runtime_error'
+        'runtime_error',
+        { question }
       )
       this.writeLog('error', `Query Agent Runtime 异常（${this.options.entry}）`, diagnostics)
       return this.fallback(request, 'runtime_error', diagnostics)
@@ -97,13 +98,13 @@ export class AskWechatService {
         engine: 'query-agent',
         status: 'error',
         message: EMPTY_QUESTION_MESSAGE,
-        diagnostics: this.diagnostics(result, startedAt, 'invalid_question')
+        diagnostics: this.diagnostics(result, startedAt, 'invalid_question', { question })
       }
     }
 
     if (result.errorKind === 'provider_unavailable' || result.errorKind === 'provider_failure') {
       const outcome: AskWechatOutcome = result.errorKind
-      const diagnostics = this.diagnostics(result, startedAt, outcome)
+      const diagnostics = this.diagnostics(result, startedAt, outcome, { question })
       this.writeLog('warn', `查询 Provider 不可用（${this.options.entry}）`, diagnostics)
       return {
         engine: 'query-agent',
@@ -114,13 +115,13 @@ export class AskWechatService {
     }
 
     if (result.errorKind === 'tool_limit') {
-      const diagnostics = this.diagnostics(result, startedAt, 'tool_limit')
+      const diagnostics = this.diagnostics(result, startedAt, 'tool_limit', { question })
       this.writeLog('warn', `查询超出工具调用上限（${this.options.entry}）`, diagnostics)
       return this.fallback(request, 'runtime_error', diagnostics)
     }
 
     if (!result.answer?.trim()) {
-      const diagnostics = this.diagnostics(result, startedAt, 'runtime_error')
+      const diagnostics = this.diagnostics(result, startedAt, 'runtime_error', { question })
       this.writeLog('warn', `Query Agent 未返回回答（${this.options.entry}）`, diagnostics)
       return this.fallback(request, 'runtime_error', diagnostics)
     }
@@ -128,7 +129,7 @@ export class AskWechatService {
     const answer = result.answer.trim()
     // 澄清回答也记录：下一句（"是 BOBO"）需要接得上上文。
     this.memory.record(conversationKey, question, answer)
-    const diagnostics = this.diagnostics(result, startedAt, 'answered')
+    const diagnostics = this.diagnostics(result, startedAt, 'answered', { question, answer })
     this.writeLog('info', `Query Agent 回答完成（${this.options.entry}）`, diagnostics)
     return {
       engine: 'query-agent',
@@ -187,17 +188,38 @@ export class AskWechatService {
     > &
       Partial<Pick<QueryAgentResult, 'totalMs'>>,
     startedAt: number,
-    outcome: AskWechatOutcome
+    outcome: AskWechatOutcome,
+    /**
+     * 问答原文（可选）。只在本地应用日志里用，不上传、不进遥测。
+     *
+     * 排查这类"同一问题时对时错"的故障，光有工具名与次数是不够的 ——
+     * 必须能对着"问题 + 模型回答"回放，否则无法判断是理解错了、链路断了，还是索引没建。
+     */
+    content?: { question?: string; answer?: string }
   ): QueryAgentDiagnostics {
+    const traces = result.traces || []
+    // 图片 OCR 的两条结构化事实：不回读正文，只统计"取到了几条"与"当时覆盖度是多少"。
+    const imageOcrTextCount = traces.reduce(
+      (sum, trace) => sum + (trace.imageOcrTextCount || 0),
+      0
+    )
+    const coverageState = traces
+      .map((trace) => trace.imageOcrCoverageState)
+      .filter((value): value is string => typeof value === 'string')
+      .at(-1)
     return {
       entry: this.options.entry,
       provider: result.provider,
       model: result.model,
       modelCallCount: result.modelCallCount,
       toolCallCount: result.toolCallCount,
-      tools: (result.traces || []).map((trace) => trace.toolName),
+      tools: traces.map((trace) => trace.toolName),
       totalMs: result.totalMs || Date.now() - startedAt,
-      outcome
+      outcome,
+      ...(imageOcrTextCount > 0 ? { imageOcrTextCount } : {}),
+      ...(coverageState ? { imageOcrCoverageState: coverageState } : {}),
+      ...(content?.question ? { question: content.question } : {}),
+      ...(content?.answer ? { answer: content.answer } : {})
     }
   }
 
diff --git a/src/main/services/cache-service.ts b/src/main/services/cache-service.ts
index d8ff7a5..956d147 100644
--- a/src/main/services/cache-service.ts
+++ b/src/main/services/cache-service.ts
@@ -8,9 +8,12 @@ export type { CacheClearScope } from '../../shared/cache'
 
 const BOOTSTRAP_CACHE_DIR = path.join(app.getPath('userData'), 'cache', 'bootstrap')
 const KNOWLEDGE_CACHE_DIR = path.join(app.getPath('userData'), 'knowledge')
+const IMAGE_TEXT_INDEX_CACHE_DIR = path.join(app.getPath('userData'), 'image-text-index')
 
 export interface CacheClearOptions {
   beforeClearKnowledge?: () => Promise<void>
+  /** 清理图片文字索引前调用：停任务 + 关闭派生库句柄。 */
+  beforeClearImageTextIndex?: () => Promise<void>
 }
 
 function inspectDirectory(directory: string): { sizeBytes: number; fileCount: number } {
@@ -46,6 +49,7 @@ export function getCacheSummary(): CacheSummary {
   const bootstrap = inspectDirectory(BOOTSTRAP_CACHE_DIR)
   const electron = inspectDirectory(path.join(app.getPath('userData'), 'Cache'))
   const knowledge = inspectDirectory(KNOWLEDGE_CACHE_DIR)
+  const imageTextIndex = inspectDirectory(IMAGE_TEXT_INDEX_CACHE_DIR)
   const items: CacheSummaryItem[] = [
     {
       id: 'bootstrap',
@@ -65,6 +69,13 @@ export function getCacheSummary(): CacheSummary {
       description:
         '为问问微信建立的所有账号本地检索索引。清理后需手动重新建立，不影响微信原始数据。',
       ...knowledge
+    },
+    {
+      id: 'image-text-index',
+      label: '图片文字索引',
+      description:
+        '本机从微信图片里识别出的文字及其检索索引。清理后无法搜索图片中的文字，可重新建立；不影响微信原始图片与聊天记录。',
+      ...imageTextIndex
     }
   ]
   return {
@@ -89,6 +100,11 @@ export async function clearCache(
     await options.beforeClearKnowledge?.()
     await fs.remove(KNOWLEDGE_CACHE_DIR)
   }
+  if (scope === 'image-text-index' || scope === 'all') {
+    // 先停下任务再删库，避免"边写边删"。
+    await options.beforeClearImageTextIndex?.()
+    await fs.remove(IMAGE_TEXT_INDEX_CACHE_DIR)
+  }
   return getCacheSummary()
 }
 
diff --git a/src/main/services/chat-service.ts b/src/main/services/chat-service.ts
index eb57569..bf7ed00 100644
--- a/src/main/services/chat-service.ts
+++ b/src/main/services/chat-service.ts
@@ -16,6 +16,7 @@ import {
 } from '../../shared/windows-runtime'
 import { mergeRecallArchiveMessages, recordRecallArchiveMessages } from './recall-archive-service'
 import type { ExportImageQuality } from '../../shared/image-quality'
+import type { ImageMessageCountProbe } from '../../shared/image-text-index'
 import { wcdbDebugLog } from '../wcdb-debug'
 import {
   buildContactSearchIndex,
@@ -717,6 +718,34 @@ export async function listMessagesForExport(
  * batch-selection view, where loading every conversation would make opening
  * Settings noticeably slow.
  */
+/**
+ * 图片消息计数探针（SQL 统计，不解密）。
+ *
+ * 返回 `count: null` 表示**统计失败**，不是 0 张。调用方必须区分这两件事 ——
+ * 否则"数不出来"会被显示成"账号里没有图片"，用户会因此放弃建立索引。
+ */
+export async function countImageMessagesAsync(
+  userMd5: string,
+  sinceMs?: number
+): Promise<ImageMessageCountProbe> {
+  if (!dbRef) return { count: null, typeColumn: null, error: '微信数据库尚未就绪' }
+  return dbRef.getWcdb4Client().countImageMessagesAsync(userMd5, sinceMs)
+}
+
+/**
+ * 图片消息的增量水位（条数 + 最大插入序）。
+ *
+ * 增量索引**不能只比条数**：召回一张旧图的同时新增一张新图，条数不变但集合变了。
+ * 返回 null = 当前数据库不支持该统计（调用方须退化成"每轮重扫"，宁可慢也不可漏）。
+ */
+export async function imageConversationWatermarkAsync(
+  userMd5: string,
+  sinceMs?: number
+): Promise<{ count: number; maxLocalId: number } | null> {
+  if (!dbRef) return null
+  return dbRef.getWcdb4Client().imageConversationWatermarkAsync(userMd5, sinceMs)
+}
+
 export async function countVoiceMessagesAsync(
   userMd5: string,
   startTime?: number,
diff --git a/src/main/services/image-text-index-service.ts b/src/main/services/image-text-index-service.ts
new file mode 100644
index 0000000..ae879e7
--- /dev/null
+++ b/src/main/services/image-text-index-service.ts
@@ -0,0 +1,970 @@
+/**
+ * 图片文字索引编排服务。
+ *
+ * 职责边界（刻意保持单一）：
+ * - 快速统计图片消息数（SQL，**绝不解密**）
+ * - 按会话 + 批次驱动 OCR；**严格串行（concurrency = 1）**：循环体内只有一次
+ *   `await`，不存在 Promise.all 扇出，且每批之间让出 event loop
+ * - 维护 checkpoint（可暂停 / 继续 / 取消 / 重启后恢复）
+ * - 把结果写进派生库，并在**会话完成时**回调，让 Knowledge 重建该会话的索引
+ *
+ * 明确不做：
+ * - 不修改 WCDB / 不写回原始消息 / 不产生任何"OCR 消息"
+ * - 不实现图片搜索 Agent（检索继续走既有 Query Agent + Knowledge）
+ * - 不在日志里写 OCR 正文 / 真实图片路径 / wxid / 群名
+ */
+import { createHash } from 'node:crypto'
+import { existsSync } from 'node:fs'
+import {
+  IMAGE_TEXT_INDEX_BATCH_SIZE,
+  IMAGE_TEXT_INDEX_ENGINE,
+  IMAGE_OCR_RETRIABLE_FAILURE_STATES,
+  buildImageOcrArtifactKey,
+  imageTextProcessedPercent,
+  isTerminalImageOcrState,
+  type ImageMessageCountProbe,
+  type ImageMessageWatermark,
+  type ImageOcrPersistedState,
+  type ImageOcrProvenance,
+  type ImageTextIndexCountResult,
+  type ImageTextIndexCoverage,
+  type ImageTextIndexProgress,
+  type ImageTextIndexRepairResult,
+  type ImageTextIndexRunState,
+  type ImageTextIndexStartOptions,
+  type ImageTextIndexStatus,
+  type ImageTextIndexStorageStats
+} from '../../shared/image-text-index'
+import { detectSystemOcrImageFormat, type SystemOcrCapability } from '../../shared/system-ocr'
+import type * as chat from './chat-service'
+/**
+ * 消息 id 必须与 Knowledge 写入的 `knowledge_messages.message_id` 完全一致，
+ * 否则 OCR 文本贴不到消息上、Evidence 也回不到原图。真源见 knowledge/message-identity。
+ */
+import { sourceMessageId } from '../knowledge/message-identity'
+import type { ImageDecryptService } from '../image-decrypt-service'
+import {
+  ImageTextIndexStore,
+  getImageTextIndexDatabasePath,
+  removeImageTextIndexDatabase,
+  type ConversationImageOcrEntry
+} from './image-text-index-store'
+
+/** 图片消息的数据 URL 前缀。 */
+const MIME_BY_FORMAT: Record<string, string> = {
+  png: 'image/png',
+  jpeg: 'image/jpeg',
+  gif: 'image/gif',
+  bmp: 'image/bmp',
+  webp: 'image/webp',
+  tiff: 'image/tiff'
+}
+
+export interface ImageTextIndexServiceDeps {
+  /** `<userData>/image-text-index`。 */
+  databaseRoot?: string
+  /** 当前账号（wxid 优先，退回 accountRoot）。空串 = 微信未就绪。 */
+  resolveAccountId?: () => string
+  /** 当前微信数据根目录。 */
+  resolveAccountRoot?: () => string
+  listContacts?: () => Promise<Array<{ md5: string; m_nsUsrName: string; type: 'user' | 'group' }>>
+  listMessages?: (conversationId: string) => Promise<chat.FormattedMessage[]>
+  /**
+   * 单个会话的图片消息计数探针（SQL 统计，不解密）。
+   *
+   * `count: null` = 统计失败，**不等于 0 张**；调用方必须区分。
+   */
+  countConversationImages?: (
+    conversationId: string,
+    sinceMs?: number
+  ) => Promise<ImageMessageCountProbe>
+  /**
+   * 单个会话的图片消息增量水位（条数 + 最大插入序），SQL 聚合，不解密。
+   *
+   * 返回 null = 当前数据库不支持（调用方必须退化成"每轮重扫"，宁可慢也不可漏）。
+   */
+  imageWatermark?: (conversationId: string, sinceMs?: number) => Promise<ImageMessageWatermark | null>
+  decryptService?: () => ImageDecryptService | null
+  /** 本地 OCR。 */
+  recognize?: (imageDataUrl: string) => Promise<{
+    success: boolean
+    text: string
+    language: string | null
+    errorCode?: string
+  }>
+  capability?: () => Promise<SystemOcrCapability>
+  /** 会话图片全部处理完后回调，用于把 OCR 文本灌进 Knowledge 索引。 */
+  onConversationIndexed?: (conversationId: string) => Promise<void>
+  /** 交互查询让路钩子。 */
+  interactiveIdle?: () => Promise<void>
+  now?: () => number
+}
+
+function sha256Short(value: Uint8Array | string): string {
+  return createHash('sha256').update(value).digest('hex').slice(0, 32)
+}
+
+/** 图片消息判定：与 chat-service 的 `contentData.type === 'image'` 对齐。 */
+export function isImageMessage(message: chat.FormattedMessage): boolean {
+  return message.contentData?.type === 'image'
+}
+
+export class ImageTextIndexService {
+  private deps: ImageTextIndexServiceDeps = {}
+  private store: ImageTextIndexStore | null = null
+  private storeAccountId = ''
+  private accountKey = ''
+  private running = false
+  private cancelRequested = false
+  private pauseRequested = false
+  private passPromise: Promise<void> | null = null
+  private counting = false
+  private listeners = new Set<(status: ImageTextIndexStatus) => void>()
+  private lastError: string | undefined
+  private startedAt: number | undefined
+  /** 上一次清理实际重建（失效）了多少个会话的 Knowledge 索引；用于诊断与测试。 */
+  lastInvalidatedConversations = 0
+  /**
+   * 会话级 OCR 文本缓存。
+   *
+   * Knowledge 重建一个会话时会对每条消息问一次 resolver；不加缓存就是每条消息一次 SQL。
+   * 写入 binding 时精确失效该会话，保证不会读到旧结果。
+   */
+  private conversationOcrCache = new Map<string, Map<string, ConversationImageOcrEntry>>()
+
+  /** 本轮 pass 的计数器（内存态；真实来源始终是派生库）。 */
+  private counters = {
+    totalImageMessages: 0,
+    processedThisPass: 0,
+    indexed: 0,
+    empty: 0,
+    missing: 0,
+    failed: 0
+  }
+
+  private runState: ImageTextIndexRunState = 'idle'
+
+  bind(deps: ImageTextIndexServiceDeps): void {
+    this.deps = { ...this.deps, ...deps }
+  }
+
+  private now(): number {
+    return this.deps.now ? this.deps.now() : Date.now()
+  }
+
+  // ------------------------------------------------------------- store 生命周期
+
+  private resolveAccountId(): string {
+    return this.deps.resolveAccountId?.() || ''
+  }
+
+  private ensureStore(): ImageTextIndexStore | null {
+    const root = this.deps.databaseRoot
+    const accountId = this.resolveAccountId()
+    if (!root || !accountId) return null
+    if (this.store && this.storeAccountId === accountId) return this.store
+    this.store?.close()
+    const key = getImageTextIndexDatabasePath(root, accountId)
+    this.store = new ImageTextIndexStore(key, accountId)
+    this.storeAccountId = accountId
+    this.accountKey = key
+    return this.store
+  }
+
+  /**
+   * 账号切换 / 数据库切换时丢弃句柄。
+   *
+   * 派生库按 accountId 分目录，句柄必须跟着换；否则会把 A 账号的 OCR
+   * 写到 B 账号，或让新库读到旧账号的 coverage。
+   */
+  resetAccount(): void {
+    this.conversationOcrCache.clear()
+    this.store?.close()
+    this.store = null
+    this.storeAccountId = ''
+    this.accountKey = ''
+    this.counters = {
+      totalImageMessages: 0,
+      processedThisPass: 0,
+      indexed: 0,
+      empty: 0,
+      missing: 0,
+      failed: 0
+    }
+    this.runState = 'idle'
+    this.cancelRequested = false
+    this.pauseRequested = false
+    this.lastError = undefined
+  }
+
+  // ------------------------------------------------------------------- 只读接口
+
+  /** Knowledge 索引时用：把某会话的 OCR 文本贴到消息上（与语音 resolver 同构）。 */
+  getConversationOcr(conversationId: string): Map<string, ConversationImageOcrEntry> {
+    const cached = this.conversationOcrCache.get(conversationId)
+    if (cached) return cached
+    const store = this.ensureStore()
+    if (!store) return new Map()
+    const result = store.getConversationOcr(conversationId)
+    this.conversationOcrCache.set(conversationId, result)
+    return result
+  }
+
+  /**
+   * 覆盖度。
+   *
+   * **分母只能来自落盘的 SQL 统计**，不能从派生库自己推：派生库只知道自己处理过什么。
+   * 如果按 `processed + pending` 反推 total，应用重启后 pending 无处可来，
+   * total 就会退化成 processed —— 30% 的部分索引会被谎报成"已覆盖全部"。
+   * 这正是 §18 禁止的"把 partial coverage 当 complete"。
+   */
+  private coverageFromCounts(counts: Record<string, number>): ImageTextIndexCoverage {
+    const indexed = counts['indexed'] ?? 0
+    const empty = counts['empty'] ?? 0
+    const missing = (counts['image_missing'] ?? 0) + (counts['metadata_missing'] ?? 0)
+    const failed =
+      (counts['decrypt_failed'] ?? 0) +
+      (counts['decode_failed'] ?? 0) +
+      (counts['ocr_failed'] ?? 0) +
+      (counts['cancelled'] ?? 0)
+    const runtimeUnavailable = counts['decrypt_unavailable'] ?? 0
+    // 运行时不可用**不计入 processed**：它不是"这条图片已经处理过了"。
+    const processed = indexed + empty + missing + failed
+    const counted = this.store?.readCountedTotal() ?? null
+    // 内存计数器只在本轮 pass 内比落盘值更新（刚统计完、尚未落盘的窗口）。
+    const total =
+      this.counters.totalImageMessages || counted?.total || processed + runtimeUnavailable
+    /**
+     * 系统性失败：处理过一批，但一条都没能给出确定结果。
+     *
+     * 这正是本次事故的形态（45,479 张全部失败，成功 / 无文字 / 缺失都是 0）。
+     * 它必须阻断 `complete` —— 否则 Query Agent 会拿着"覆盖完整"去回答"没有"。
+     */
+    const systemicFailure = processed > 0 && indexed === 0 && empty === 0 && missing === 0
+    return {
+      totalImageMessages: total,
+      processed,
+      indexed,
+      empty,
+      missing,
+      failed,
+      runtimeUnavailable,
+      pending: Math.max(0, total - processed - runtimeUnavailable),
+      // 从未统计过总数 → 不算"已建立"：不知道分母就不允许声称覆盖。
+      established: counted !== null && (processed > 0 || runtimeUnavailable > 0),
+      // 分母不完整、有 pending、有运行时不可用、或"全军覆没" → 都不算 complete。
+      complete:
+        counted !== null &&
+        counted.complete &&
+        total > 0 &&
+        runtimeUnavailable === 0 &&
+        !systemicFailure &&
+        processed >= total,
+      systemicFailure,
+      countedAt: counted?.countedAt ?? null
+    }
+  }
+
+  /**
+   * 覆盖度快照（只读、同步），供 Query Agent 在工具结果里携带图片覆盖度。
+   *
+   * 刻意**不建库**：只因为用户问了一句话就凭空创建一个派生库是没道理的。
+   * 库不存在 = 从未建立过索引 = `not_built`。
+   */
+  getCoverageSnapshot(): ImageTextIndexCoverage | null {
+    const root = this.deps.databaseRoot
+    const accountId = this.resolveAccountId()
+    if (!root || !accountId) return null
+    if (!this.store && !existsSync(getImageTextIndexDatabasePath(root, accountId))) {
+      return null
+    }
+    const store = this.ensureStore()
+    if (!store) return null
+    return this.coverageFromCounts(store.countByState())
+  }
+
+  private progressFromCounts(counts: Record<string, number>): ImageTextIndexProgress {
+    const coverage = this.coverageFromCounts(counts)
+    const total = coverage.totalImageMessages
+    const percent = imageTextProcessedPercent(coverage.processed, total)
+    return {
+      state: this.runState,
+      totalImageMessages: total,
+      processed: coverage.processed,
+      indexed: coverage.indexed,
+      empty: coverage.empty,
+      missing: coverage.missing,
+      failed: coverage.failed,
+      runtimeUnavailable: coverage.runtimeUnavailable,
+      systemicFailure: coverage.systemicFailure,
+      pending: coverage.pending,
+      percent,
+      processedPercent: percent,
+      ...(this.startedAt ? { startedAt: this.startedAt } : {}),
+      updatedAt: this.now(),
+      cancellable: this.running,
+      paused: this.runState === 'paused',
+      ...(this.lastError ? { lastError: this.lastError } : {})
+    }
+  }
+
+  private emptyStorage(): ImageTextIndexStorageStats {
+    return { indexedImages: 0, ocrTextCount: 0, totalBytes: 0, updatedAt: null }
+  }
+
+  async getStatus(): Promise<ImageTextIndexStatus> {
+    const store = this.ensureStore()
+    if (!store) {
+      return {
+        progress: {
+          state: this.runState,
+          totalImageMessages: this.counters.totalImageMessages,
+          processed: 0,
+          indexed: 0,
+          empty: 0,
+          missing: 0,
+          failed: 0,
+          runtimeUnavailable: 0,
+          systemicFailure: false,
+          pending: 0,
+          percent: 0,
+          processedPercent: 0,
+          updatedAt: this.now(),
+          cancellable: false,
+          paused: false
+        },
+        coverage: {
+          totalImageMessages: 0,
+          processed: 0,
+          indexed: 0,
+          empty: 0,
+          missing: 0,
+          failed: 0,
+          runtimeUnavailable: 0,
+          pending: 0,
+          established: false,
+          complete: false,
+          systemicFailure: false,
+          countedAt: null
+        },
+        storage: this.emptyStorage(),
+        counting: this.counting
+      }
+    }
+    const counts = store.countByState()
+    return {
+      progress: this.progressFromCounts(counts),
+      coverage: this.coverageFromCounts(counts),
+      storage: store.storageStats(),
+      counting: this.counting
+    }
+  }
+
+  onStatusChange(listener: (status: ImageTextIndexStatus) => void): () => void {
+    this.listeners.add(listener)
+    return () => this.listeners.delete(listener)
+  }
+
+  private async emit(): Promise<void> {
+    if (!this.listeners.size) return
+    const status = await this.getStatus()
+    for (const listener of this.listeners) {
+      try {
+        listener(status)
+      } catch {
+        // 监听器异常不得影响索引。
+      }
+    }
+  }
+
+  // --------------------------------------------------------------------- 统计
+
+  /**
+   * 快速统计当前账号的图片消息数。
+   *
+   * 走 SQL COUNT（`local_type & 65535 = 3`），**不解密任何图片** —— 这是
+   * 「点击索引前先告诉用户有多少张」能够足够快的前提。
+   */
+  async countImageMessages(sinceMs?: number): Promise<ImageTextIndexCountResult> {
+    const startedAt = this.now()
+    const contacts = await (this.deps.listContacts?.() ?? Promise.resolve([]))
+    let total = 0
+    let scanned = 0
+    let failed = 0
+    let typeColumn: string | null = null
+    let firstError: string | undefined
+    for (const contact of contacts) {
+      const probe = await (this.deps.countConversationImages?.(contact.md5, sinceMs) ??
+        Promise.resolve<ImageMessageCountProbe>({
+          count: null,
+          typeColumn: null,
+          error: '未接入图片消息统计能力'
+        }))
+      if (probe.typeColumn && !typeColumn) typeColumn = probe.typeColumn
+      if (probe.count === null) {
+        // **统计失败不是 0 张**：必须单独计数，否则 UI 会把"数不出来"说成"没有图片"。
+        failed += 1
+        if (!firstError) firstError = probe.error
+        continue
+      }
+      scanned += 1
+      total += probe.count
+    }
+    this.counters.totalImageMessages = total
+    // 落盘：coverage 的分母必须能被重启后读到（见 coverageFromCounts）。
+    // 只要有一个会话没数上，分母就是偏小的 → 标记为不完整，coverage 拿不到 complete。
+    this.ensureStore()?.writeCountedTotal({
+      total,
+      countedAt: this.now(),
+      complete: contacts.length > 0 && failed === 0
+    })
+    return {
+      totalImageMessages: total,
+      scannedConversations: scanned,
+      failedConversations: failed,
+      typeColumn,
+      ...(firstError ? { error: firstError } : {}),
+      durationMs: this.now() - startedAt
+    }
+  }
+
+  // ------------------------------------------------------------------ 单张处理
+
+  private async processOne(
+    message: chat.FormattedMessage,
+    conversationId: string,
+    provenance: ImageOcrProvenance
+  ): Promise<{ state: ImageOcrPersistedState; text: string; imageIdentity: string | null }> {
+    const imageContent =
+      message.contentData?.type === 'image'
+        ? (message.contentData as { md5?: string; datName?: string })
+        : undefined
+
+    const decrypt = this.deps.decryptService?.() ?? null
+    /**
+     * 解密服务缺失是**运行时**问题，不是这张图片的问题。
+     *
+     * 本次事故就是它：`imageDecryptService` 只在用户点开某张图时才懒加载，
+     * 于是全量回填 45,479 张全部落成 `decrypt_failed` —— 数字看着像"图片坏了"，
+     * 实际是流水线前置依赖没接上。这里必须用独立状态，绝不能与真正的解密失败混为一谈。
+     */
+    if (!decrypt) return { state: 'decrypt_unavailable', text: '', imageIdentity: null }
+
+    // 图片消息缺少定位字段：连"去哪找文件"都不知道，属消息侧缺失而非 OCR 失败。
+    if (!imageContent?.md5 && !imageContent?.datName) {
+      return { state: 'metadata_missing', text: '', imageIdentity: null }
+    }
+
+    let datPath: string | null = null
+    try {
+      datPath = decrypt.findImageFile(imageContent?.md5, imageContent?.datName, {
+        accountDir: this.deps.resolveAccountRoot?.() || undefined,
+        sessionMd5: conversationId,
+        createTime: message.createTime,
+        allowThumbnail: true,
+        preferThumbnail: true
+      })
+    } catch {
+      datPath = null
+    }
+    // 微信清理过原图与缩略图 —— 这是正常情况，不是任务级错误。
+    if (!datPath) return { state: 'image_missing', text: '', imageIdentity: null }
+
+    let bytes: Buffer | null = null
+    try {
+      bytes = decrypt.decryptImage(datPath)
+    } catch {
+      bytes = null
+    }
+    if (!bytes || bytes.length === 0) {
+      return { state: 'decrypt_failed', text: '', imageIdentity: null }
+    }
+
+    const imageIdentity = `sha256:${sha256Short(bytes)}`
+    const format = detectSystemOcrImageFormat(bytes)
+    // 解密"没抛错"但产出不是图片 → 解码失败，不是 OCR 失败。
+    if (!format) return { state: 'decode_failed', text: '', imageIdentity }
+
+    const store = this.ensureStore()
+    const artifactKey = buildImageOcrArtifactKey({ imageIdentity, provenance })
+
+    // 同一张图（可能被转发到多个会话）已经算过 → 直接复用，绝不重复 OCR。
+    const cached = store?.getArtifact(artifactKey) ?? null
+    if (cached && isTerminalImageOcrState(cached.state)) {
+      return { state: cached.state, text: cached.text, imageIdentity }
+    }
+
+    const mime = MIME_BY_FORMAT[format] ?? 'image/png'
+    let state: ImageOcrPersistedState = 'ocr_failed'
+    let text = ''
+    let errorCode: string | undefined
+    try {
+      const result = await (this.deps.recognize?.(`data:${mime};base64,${bytes.toString('base64')}`) ??
+        Promise.resolve({ success: false, text: '', language: null, errorCode: 'OCR_FAILED' }))
+      if (result.success && result.text.trim()) {
+        state = 'indexed'
+        text = result.text
+      } else if (result.success || result.errorCode === 'OCR_EMPTY_RESULT') {
+        // 表情包 / 风景 / 头像 —— 没有文字是**正常终态**，不重试。
+        state = 'empty'
+      } else {
+        state = 'ocr_failed'
+        errorCode = result.errorCode
+      }
+    } catch {
+      state = 'ocr_failed'
+    }
+
+    const now = this.now()
+    if (store) {
+      store.putArtifact({
+        accountId: this.storeAccountId,
+        artifactKey,
+        imageIdentity,
+        state,
+        text,
+        charCount: text.length,
+        engine: provenance.engine,
+        platform: provenance.platform,
+        runtimeVersion: provenance.runtimeVersion,
+        language: provenance.language,
+        ...(errorCode ? { errorCode } : {}),
+        createdAt: now,
+        updatedAt: now
+      })
+    }
+    return { state, text, imageIdentity }
+  }
+
+  // --------------------------------------------------------------------- pass
+
+  /**
+   * 启动一次 pass。
+   *
+   * 「暂停 / 继续」刻意实现为「停止 + 重新跑一次 pass」而不是原地挂起：
+   * - checkpoint（scan_state）与 artifact 缓存都在库里，重跑会跳过已完成会话、
+   *   并且命中 artifact 缓存不再重复 OCR，所以恢复成本很低；
+   * - 与项目既有的「中断后重跑、靠 checkpoint 续做」语义一致，不引入新的挂起状态机。
+   */
+  startPass(options: ImageTextIndexStartOptions = {}): { started: boolean; state: ImageTextIndexRunState } {
+    if (this.running) return { started: false, state: this.runState }
+    this.cancelRequested = false
+    this.pauseRequested = false
+    this.lastError = undefined
+    this.startedAt = this.now()
+    this.runState = 'running'
+    this.passPromise = this.runPass(options)
+      .catch((error) => {
+        this.lastError = error instanceof Error ? error.message : String(error)
+        this.runState = 'error'
+      })
+      .finally(() => {
+        this.running = false
+        this.passPromise = null
+        void this.emit()
+      })
+    void this.emit()
+    return { started: true, state: this.runState }
+  }
+
+  private async runPass(options: ImageTextIndexStartOptions): Promise<void> {
+    const store = this.ensureStore()
+    if (!store) {
+      this.lastError = '微信数据尚未就绪'
+      this.runState = 'error'
+      return
+    }
+    this.running = true
+
+    const capability = (await this.deps.capability?.()) ?? null
+    if (capability && !capability.available) {
+      this.lastError = '当前系统不支持本地图片文字识别'
+      this.runState = 'error'
+      return
+    }
+    /**
+     * **前置依赖自检（本次事故的根因防线）**：解密服务必须可用。
+     *
+     * 没有它，每张图片都会在 `processOne` 的第一步失败。原实现会把"整条流水线
+     * 根本跑不起来"这件事落成 45,479 条 `decrypt_failed` —— 既污染派生库，
+     * 又让用户以为自己的图片坏了，还让 coverage 看起来"都处理完了"。
+     *
+     * 所以必须在**写任何一条记录之前**停下来：宁可一次都不跑，也不要写一堆假失败。
+     */
+    if (!this.deps.decryptService?.()) {
+      this.lastError = '图片解密服务尚未就绪，无法读取微信图片；本次未写入任何记录。'
+      this.runState = 'error'
+      return
+    }
+    const provenance: ImageOcrProvenance = {
+      engine: capability?.engine ?? IMAGE_TEXT_INDEX_ENGINE,
+      platform: capability?.platform ?? process.platform,
+      runtimeVersion: capability?.runtimeVersion ?? null,
+      language: capability?.language ?? null
+    }
+
+    // 统计一次总数（SQL），进度百分比才有真实分母。
+    this.counting = true
+    try {
+      await this.countImageMessages(options.sinceMs)
+    } finally {
+      this.counting = false
+    }
+
+    let contacts = await (this.deps.listContacts?.() ?? Promise.resolve([]))
+    if (options.conversationLimit && options.conversationLimit > 0) {
+      contacts = contacts.slice(0, options.conversationLimit)
+    }
+
+    const scanState = store.readScanState()
+    let budget = options.messageLimit && options.messageLimit > 0 ? options.messageLimit : Infinity
+
+    for (const contact of contacts) {
+      if (this.cancelRequested || this.pauseRequested) break
+      if (budget <= 0) break
+
+      const conversationId = contact.md5
+      /**
+       * 是否只处理一个时间窗口（用于小样本验证）。
+       *
+       * 带窗口时**不做增量跳过**：checkpoint 是围绕全量集合建立的，
+       * 窗口内的图片可能从未被处理过，继续按"该会话已完成"跳过会让窗口形同虚设。
+       */
+      const windowed = Boolean(options.sinceMs && options.sinceMs > 0)
+      // 增量水位 = 条数 + 最大插入序（§2）。只比条数会漏掉「撤回一张旧图 +
+      // 新增一张新图」这种总数不变、集合却变了的会话。
+      const watermark = await (this.deps.imageWatermark?.(conversationId, options.sinceMs) ??
+        Promise.resolve(null))
+      const imageTotal =
+        watermark?.count ??
+        (await this.deps.countConversationImages?.(conversationId, options.sinceMs))?.count ??
+        0
+      if (imageTotal === 0) {
+        store.writeScanState({
+          conversationId,
+          state: 'done',
+          imageTotal: 0,
+          imageProcessed: 0,
+          maxLocalId: watermark?.maxLocalId ?? 0
+        })
+        continue
+      }
+
+      // 增量：会话已完成且**水位完全未变** → 不读 WCDB、不 OCR。
+      // 水位不可用时（数据库不支持该聚合）一律重扫：宁可慢，不可漏。
+      const previous = scanState.get(conversationId)
+      if (
+        !windowed &&
+        watermark &&
+        previous &&
+        previous.state === 'done' &&
+        previous.imageTotal === watermark.count &&
+        previous.maxLocalId === watermark.maxLocalId
+      ) {
+        continue
+      }
+
+      await this.deps.interactiveIdle?.()
+
+      let messages: chat.FormattedMessage[] = []
+      try {
+        messages = await (this.deps.listMessages?.(conversationId) ?? Promise.resolve([]))
+      } catch {
+        messages = []
+      }
+      const imageMessages = messages
+        .filter(isImageMessage)
+        // 时间窗过滤：小样本验证时只看窗口内的图片，不然还是在跑全量。
+        .filter((message) =>
+          windowed ? (message.createTime || 0) * 1000 >= (options.sinceMs as number) : true
+        )
+      if (!imageMessages.length) {
+        store.writeScanState({
+          conversationId,
+          state: 'done',
+          imageTotal: 0,
+          imageProcessed: 0,
+          maxLocalId: 0
+        })
+        continue
+      }
+      // 水位取**实际读到的**消息里最大的 local_id，而不是源侧水位：
+      // 万一在我们查水位之后、读消息之前又落了一条新图，用观测值会让下一轮
+      // 发现"源水位更高"从而重扫（安全）；用源侧水位则会把它永久跳过（漏索引）。
+      const observedMaxLocalId = imageMessages.reduce(
+        (max, message) => Math.max(max, Number(message.localId) || 0),
+        0
+      )
+
+      const ocrByMessage = store.getConversationOcr(conversationId)
+      let processedInConversation = 0
+      let interrupted = false
+
+      for (let index = 0; index < imageMessages.length; index += IMAGE_TEXT_INDEX_BATCH_SIZE) {
+        if (this.cancelRequested || this.pauseRequested) {
+          interrupted = true
+          break
+        }
+        const batch = imageMessages.slice(index, index + IMAGE_TEXT_INDEX_BATCH_SIZE)
+
+        for (const message of batch) {
+          if (budget <= 0) break
+          const messageId = sourceMessageId(message)
+
+          // 派生库里已有终态结果 → 复用（含"无文字"/"图片缺失"），不重复劳动。
+          const known = ocrByMessage.get(messageId)
+          if (known && isTerminalImageOcrState(known.state)) {
+            processedInConversation += 1
+            continue
+          }
+
+          const outcome = await this.processOne(message, conversationId, provenance)
+          const now = this.now()
+          store.putBinding({
+            accountId: this.storeAccountId,
+            conversationId,
+            messageId,
+            createTime: (message.createTime || 0) * 1000,
+            ...(message.senderId || message.from ? { senderId: message.senderId || message.from } : {}),
+            ...(message.isSender ? { senderName: '我' } : message.name ? { senderName: message.name } : {}),
+            imageIdentity: outcome.imageIdentity ?? '',
+            artifactKey: outcome.imageIdentity
+              ? buildImageOcrArtifactKey({ imageIdentity: outcome.imageIdentity, provenance })
+              : buildImageOcrArtifactKey({ imageIdentity: 'unavailable', provenance }),
+            state: outcome.state,
+            updatedAt: now
+          })
+
+          this.conversationOcrCache.delete(conversationId)
+          processedInConversation += 1
+          this.counters.processedThisPass += 1
+          if (outcome.state === 'indexed') this.counters.indexed += 1
+          else if (outcome.state === 'empty') this.counters.empty += 1
+          else if (outcome.state === 'image_missing') this.counters.missing += 1
+          else this.counters.failed += 1
+          budget -= 1
+        }
+
+        // 批次之间让出 event loop：交互查询 / UI 永远优先于后台历史 OCR。
+        await new Promise<void>((resolve) => setImmediate(resolve))
+        await this.emit()
+      }
+
+      if (interrupted) {
+        store.writeScanState({
+          conversationId,
+          state: 'partial',
+          imageTotal: imageMessages.length,
+          imageProcessed: processedInConversation,
+          maxLocalId: observedMaxLocalId
+        })
+        break
+      }
+
+      store.writeScanState({
+        conversationId,
+        state: 'done',
+        imageTotal: imageMessages.length,
+        imageProcessed: processedInConversation,
+        maxLocalId: observedMaxLocalId
+      })
+
+      // 会话的图片都处理完了 → 让 Knowledge 重建这个会话，OCR 文本才可被搜索。
+      try {
+        await this.deps.onConversationIndexed?.(conversationId)
+      } catch {
+        // 索引回调失败不应中断 OCR：派生文本已经落库，下一遍还会再灌。
+      }
+      await this.emit()
+    }
+
+    if (this.cancelRequested) this.runState = 'cancelled'
+    else if (this.pauseRequested) this.runState = 'paused'
+    else this.runState = 'completed'
+    this.running = false
+    await this.emit()
+  }
+
+  // --------------------------------------------------------------- 控制接口
+
+  pause(): { paused: boolean; state: ImageTextIndexRunState } {
+    if (!this.running) return { paused: false, state: this.runState }
+    this.pauseRequested = true
+    return { paused: true, state: 'paused' }
+  }
+
+  resume(options: ImageTextIndexStartOptions = {}): { started: boolean; state: ImageTextIndexRunState } {
+    if (this.running) return { started: false, state: this.runState }
+    return this.startPass(options)
+  }
+
+  async cancel(): Promise<{ cancellable: boolean; cancelled: boolean }> {
+    if (!this.running) return { cancellable: false, cancelled: false }
+    this.cancelRequested = true
+    const pending = this.passPromise
+    if (pending) await pending.catch(() => undefined)
+    return { cancellable: true, cancelled: true }
+  }
+
+  isRunning(): boolean {
+    return this.running
+  }
+
+  // ------------------------------------------------------------------- 清理
+
+  /**
+   * 清理「图片文字索引能力」的全部派生数据。
+   *
+   * 只删本能力自己生成的东西：artifact（OCR 文本）、binding、checkpoint、库文件。
+   * 明确**不碰**：WCDB、微信图片、图片解密密钥、普通文字知识库、语音转写、聊天消息、Agent 配置。
+   */
+  async clear(): Promise<{ removed: boolean; removedBytes: number }> {
+    await this.cancel()
+    this.conversationOcrCache.clear()
+    const store = this.ensureStore()
+    /**
+     * **必须在删之前**记下受影响会话。
+     *
+     * OCR 派生文本已经通过 normalizer 进了 Knowledge 的 chunks / FTS。
+     * 只删派生库、不做这一步，用户执行「清理图片文字索引」之后**仍然能搜到图片里的文字** ——
+     * 那就等于"清理成功"是假的。硬条件：清理图片文字索引 ≠ 只删 OCR SQLite。
+     */
+    const affectedConversations = store?.conversationIdsWithOcr() ?? []
+    let removedBytes = 0
+    if (store) {
+      removedBytes = store.storageStats().totalBytes
+      store.clearDerivedData()
+      // 先折 WAL 再关连接，然后才允许删文件（见 store.close / removeImageTextIndexDatabase）。
+      store.close()
+      this.store = null
+      this.storeAccountId = ''
+    }
+    const databasePath = this.accountKey
+    this.accountKey = ''
+    const removal = databasePath
+      ? removeImageTextIndexDatabase(databasePath)
+      : { removed: true, leftovers: [] as string[] }
+    // 总数统计也一并作废：下次回到「未建立」时重新 COUNT(*)，
+    // 否则 UI 会拿着一个已经没有任何派生数据支撑的旧分母。
+    this.counters = {
+      totalImageMessages: 0,
+      processedThisPass: 0,
+      indexed: 0,
+      empty: 0,
+      missing: 0,
+      failed: 0
+    }
+    this.runState = 'idle'
+    this.startedAt = undefined
+    await this.emit()
+
+    /**
+     * 逐个重建**受影响的会话**，让 OCR 派生文本从 Knowledge 里消失。
+     *
+     * 刻意不做两件更省事但更糟的事：
+     * - 不清空整个 Knowledge（那会连普通文字消息的索引一起丢掉）；
+     * - 不假装"删了文件就等于清理完成"（chunks/FTS 里还留着旧文字）。
+     *
+     * rebuilt 这里已经返回空（派生库已删、resolver 拿不到 OCR），所以重建出来的
+     * 会话副本天然不含 OCR 文本；`completeSnapshot` 会把旧的 chunk 一起替换掉。
+     */
+    let invalidatedConversations = 0
+    for (const conversationId of affectedConversations) {
+      try {
+        await this.deps.onConversationIndexed?.(conversationId)
+        invalidatedConversations += 1
+      } catch {
+        // 单个会话重建失败不应让清理整体失败：派生数据已经删了，
+        // 下一遍索引也会因为 resolver 返回空而自然收敛。
+      }
+    }
+    this.lastInvalidatedConversations = invalidatedConversations
+    /**
+     * 重建过程中 Knowledge 会通过 resolver 调 `getConversationOcr`，
+     * 那会把派生库**重新打开**（`ensureStore`）。清理完必须再收干净：
+     * 否则「清理成功」之后还留着一个空库句柄，Windows 上也会妨碍目录删除。
+     */
+    this.store?.close()
+    this.store = null
+    this.storeAccountId = ''
+    this.accountKey = ''
+    // `removed: false` = 文件仍被占用没删掉，必须如实上报，不能假装清理成功。
+    return { removed: removal.removed, removedBytes }
+  }
+
+  /**
+   * 缓存清理前先停下任务，并**把 Knowledge 里的 OCR 派生文本一起失效**。
+   *
+   * 直接复用 `clear()` 而不是只 `cancel()`：缓存清理（含"清理全部"）同样会删掉派生库，
+   * 如果这里不顺手重建 Knowledge，用户会得到一个自相矛盾的状态 ——
+   * 「问问微信」里搜得到图片文字，但派生库明明已经没了。
+   */
+  async prepareForCacheClear(): Promise<void> {
+    await this.clear()
+  }
+
+  /**
+   * 派生索引修复（Derived Index Repair）。
+   *
+   * 只重建 **L3（Knowledge 派生条目 / chunks / FTS）**，数据来源是已有的
+   * L2 binding + L1 artifact。**绝不**读原图、解密或调用 OCR 引擎 ——
+   * L1 是几万张图片堆出来的昂贵产物，修一个索引问题不该让它重算一遍。
+   *
+   * `ocrExecutions: 0` 不是"期望"，而是这条路径的定义：类型上写死成字面量 0，
+   * 任何让它变成非 0 的改动都会直接编译失败。
+   */
+  async repairKnowledgeIndex(
+    options: { conversationLimit?: number } = {}
+  ): Promise<ImageTextIndexRepairResult> {
+    const startedAt = this.now()
+    // 运行中不并发重建：pass 正在写 binding，同时重建会让 Knowledge 读到半程状态。
+    if (this.running) {
+      return { conversations: 0, ocrExecutions: 0, durationMs: 0, skipped: true }
+    }
+    const store = this.ensureStore()
+    if (!store) {
+      return { conversations: 0, ocrExecutions: 0, durationMs: this.now() - startedAt, skipped: false }
+    }
+    const limit = options.conversationLimit && options.conversationLimit > 0 ? options.conversationLimit : undefined
+    const conversationIds = limit
+      ? store.conversationIdsWithIndexedOcr().slice(0, limit)
+      : store.conversationIdsWithIndexedOcr()
+
+    let conversations = 0
+    for (const conversationId of conversationIds) {
+      try {
+        await this.deps.onConversationIndexed?.(conversationId)
+        conversations += 1
+      } catch {
+        // 单个会话重建失败不影响其余：修索引是尽力而为的廉价操作，可重试。
+      }
+    }
+    return {
+      conversations,
+      ocrExecutions: 0,
+      durationMs: this.now() - startedAt,
+      skipped: false
+    }
+  }
+
+  /**
+   * 重置**可重试的失败记录**（代码修好之后重跑用）。
+   *
+   * 刻意不做成"清空整个派生库"：那会连已经成功的 OCR 记录一起丢掉，
+   * 用户要为此重新跑几万张图片。这里只删失败绑定 + 它们的 checkpoint，
+   * `indexed` / `empty` 一条不动，下一轮 pass 自然接上。
+   */
+  async resetRetriableFailures(): Promise<{ reset: number }> {
+    await this.cancel()
+    this.conversationOcrCache.clear()
+    const store = this.ensureStore()
+    if (!store) return { reset: 0 }
+    const reset = store.resetFailures([...IMAGE_OCR_RETRIABLE_FAILURE_STATES])
+    await this.emit()
+    return { reset }
+  }
+
+  /** 缓存清理前先停下任务，避免边删边写。 */
+}
+
+export const imageTextIndexService = new ImageTextIndexService()
diff --git a/src/main/services/image-text-index-store.ts b/src/main/services/image-text-index-store.ts
new file mode 100644
index 0000000..013b15f
--- /dev/null
+++ b/src/main/services/image-text-index-store.ts
@@ -0,0 +1,572 @@
+/**
+ * 图片文字索引的**派生存储**（与 Knowledge 派生库物理分离）。
+ *
+ * 为什么单独一个库而不是往 knowledge.sqlite 里加表：
+ * - 清理语义干净：整个能力 = 三个文件（.sqlite/-wal/-shm），删掉即可，不留残渣。
+ * - 零迁移风险：不动已发布的 knowledge schema（§26 要求升级不破坏既有派生库）。
+ * - 去重语义天然：artifact 按「图片内容 + OCR 运行时指纹」唯一，binding 承担多来源。
+ *
+ * 账号隔离与 Knowledge 一致：路径按 accountId 摘要分目录 + 库内 account_id 自证。
+ */
+import { createHash } from 'node:crypto'
+import { mkdirSync, rmSync, statSync, existsSync } from 'node:fs'
+import { dirname, join, resolve } from 'node:path'
+import { DatabaseSync } from 'node:sqlite'
+import {
+  IMAGE_TEXT_INDEX_SCHEMA_VERSION,
+  type ImageOcrArtifact,
+  type ImageOcrBinding,
+  type ImageOcrPersistedState,
+  type ImageTextIndexStorageStats
+} from '../../shared/image-text-index'
+
+const MAX_SAFE_ACCOUNT_SEGMENT = /^[a-f0-9]{32}$/
+
+function sha256Hex(value: string): string {
+  return createHash('sha256').update(value).digest('hex')
+}
+
+/** 派生库目录名不直接暴露 accountId。 */
+export function imageTextIndexAccountKey(accountId: string): string {
+  return sha256Hex(`image-text-index-account-v1:${accountId}`).slice(0, 32)
+}
+
+export function getImageTextIndexDatabasePath(databaseRoot: string, accountId: string): string {
+  const accountKey = imageTextIndexAccountKey(accountId)
+  if (!MAX_SAFE_ACCOUNT_SEGMENT.test(accountKey)) {
+    throw new Error('Invalid image text index account key')
+  }
+  return join(resolve(databaseRoot), accountKey, 'image-text-index.sqlite')
+}
+
+/**
+ * 精确删除三件套（与 Knowledge 的 removeKnowledgeDatabase 同构）。
+ *
+ * **删除后必须回验**：Windows 上只要还有句柄（WAL/SHM 未关干净、别的进程打开了库），
+ * `rmSync` 可能不报错却没真的删掉 —— 那就是"看似清理成功，实际没删"。
+ * 这里把没删掉的路径返回给调用方，让上层能如实报告失败，而不是假装成功。
+ */
+export function removeImageTextIndexDatabase(databasePath: string): {
+  removed: boolean
+  leftovers: string[]
+} {
+  const leftovers: string[] = []
+  for (const suffix of ['', '-wal', '-shm']) {
+    const target = `${databasePath}${suffix}`
+    if (!existsSync(target)) continue
+    try {
+      rmSync(target, { force: true })
+    } catch {
+      // 删除失败（典型原因是文件仍被占用）→ 由下面的回验兜住。
+    }
+    if (existsSync(target)) leftovers.push(target)
+  }
+  return { removed: leftovers.length === 0, leftovers }
+}
+
+function asRows(value: unknown): Record<string, unknown>[] {
+  return Array.isArray(value) ? (value as Record<string, unknown>[]) : []
+}
+
+function artifactFromRow(row: Record<string, unknown>): ImageOcrArtifact {
+  return {
+    accountId: String(row.account_id),
+    artifactKey: String(row.artifact_key),
+    imageIdentity: String(row.image_identity),
+    state: String(row.state) as ImageOcrPersistedState,
+    text: String(row.text ?? ''),
+    charCount: Number(row.char_count ?? 0),
+    engine: String(row.engine),
+    platform: String(row.platform),
+    runtimeVersion: row.runtime_version ? String(row.runtime_version) : null,
+    language: row.language ? String(row.language) : null,
+    ...(row.error_code ? { errorCode: String(row.error_code) } : {}),
+    createdAt: Number(row.created_at),
+    updatedAt: Number(row.updated_at)
+  }
+}
+
+/** 会话内「消息 → OCR 文本」，供 Knowledge 索引时解析（与语音 resolver 同构）。 */
+export interface ConversationImageOcrEntry {
+  state: ImageOcrPersistedState
+  text: string
+}
+
+export class ImageTextIndexStore {
+  private readonly database: DatabaseSync
+
+  constructor(
+    private readonly databasePath: string,
+    private readonly accountId: string
+  ) {
+    mkdirSync(dirname(databasePath), { recursive: true })
+    this.database = new DatabaseSync(databasePath)
+    this.initialize()
+  }
+
+  private initialize(): void {
+    this.database.exec(`
+      PRAGMA journal_mode = WAL;
+      PRAGMA synchronous = NORMAL;
+      PRAGMA busy_timeout = 5000;
+      CREATE TABLE IF NOT EXISTS image_ocr_meta (
+        key TEXT PRIMARY KEY,
+        value TEXT NOT NULL
+      ) STRICT;
+      CREATE TABLE IF NOT EXISTS image_ocr_artifacts (
+        artifact_key TEXT PRIMARY KEY,
+        account_id TEXT NOT NULL,
+        image_identity TEXT NOT NULL,
+        state TEXT NOT NULL,
+        text TEXT NOT NULL,
+        char_count INTEGER NOT NULL DEFAULT 0,
+        engine TEXT NOT NULL,
+        platform TEXT NOT NULL,
+        runtime_version TEXT,
+        language TEXT,
+        error_code TEXT,
+        created_at INTEGER NOT NULL,
+        updated_at INTEGER NOT NULL
+      ) STRICT;
+      CREATE INDEX IF NOT EXISTS image_ocr_artifacts_identity
+        ON image_ocr_artifacts (image_identity);
+      CREATE TABLE IF NOT EXISTS image_ocr_bindings (
+        conversation_id TEXT NOT NULL,
+        message_id TEXT NOT NULL,
+        account_id TEXT NOT NULL,
+        create_time INTEGER NOT NULL,
+        sender_id TEXT,
+        sender_name TEXT,
+        image_identity TEXT NOT NULL,
+        artifact_key TEXT NOT NULL,
+        state TEXT NOT NULL,
+        updated_at INTEGER NOT NULL,
+        PRIMARY KEY (conversation_id, message_id)
+      ) STRICT;
+      CREATE INDEX IF NOT EXISTS image_ocr_bindings_identity
+        ON image_ocr_bindings (image_identity);
+      CREATE INDEX IF NOT EXISTS image_ocr_bindings_state
+        ON image_ocr_bindings (state);
+      -- 每个会话的扫描 checkpoint：重启后据此跳过已完成的会话。
+      CREATE TABLE IF NOT EXISTS image_ocr_scan_state (
+        conversation_id TEXT PRIMARY KEY,
+        account_id TEXT NOT NULL,
+        state TEXT NOT NULL,
+        image_total INTEGER NOT NULL DEFAULT 0,
+        image_processed INTEGER NOT NULL DEFAULT 0,
+        image_max_local_id INTEGER NOT NULL DEFAULT 0,
+        updated_at INTEGER NOT NULL
+      ) STRICT;
+    `)
+
+    // 探测式加列（与 Knowledge 一致）：旧库缺列时补上，不做版本号比较。
+    const bindingColumns = new Set(
+      asRows(this.database.prepare('PRAGMA table_info(image_ocr_bindings)').all()).map((row) =>
+        String(row.name)
+      )
+    )
+    if (!bindingColumns.has('artifact_key')) {
+      this.database.exec(
+        "ALTER TABLE image_ocr_bindings ADD COLUMN artifact_key TEXT NOT NULL DEFAULT ''"
+      )
+    }
+
+    const scanColumns = new Set(
+      asRows(this.database.prepare('PRAGMA table_info(image_ocr_scan_state)').all()).map((row) =>
+        String(row.name)
+      )
+    )
+    if (!scanColumns.has('image_max_local_id')) {
+      // 旧库补列后默认 0：等于「水位未知」，下一次 pass 会重扫该会话并写入真实水位。
+      this.database.exec(
+        'ALTER TABLE image_ocr_scan_state ADD COLUMN image_max_local_id INTEGER NOT NULL DEFAULT 0'
+      )
+    }
+
+    const storedAccount = this.readMeta('account_id')
+    if (storedAccount && storedAccount !== this.accountId) {
+      throw new Error('Image text index account isolation check failed')
+    }
+    if (!storedAccount) this.writeMeta('account_id', this.accountId)
+    if (!this.readMeta('schema_version')) {
+      this.writeMeta('schema_version', String(IMAGE_TEXT_INDEX_SCHEMA_VERSION))
+    }
+  }
+
+  private readMeta(key: string): string | null {
+    const row = this.database
+      .prepare('SELECT value FROM image_ocr_meta WHERE key = ?')
+      .get(key) as Record<string, unknown> | undefined
+    return row ? String(row.value) : null
+  }
+
+  private writeMeta(key: string, value: string): void {
+    this.database
+      .prepare(
+        'INSERT INTO image_ocr_meta (key, value) VALUES (?, ?) ON CONFLICT(key) DO UPDATE SET value = excluded.value'
+      )
+      .run(key, value)
+  }
+
+  // ---------------------------------------------------------------- artifacts
+
+  getArtifact(artifactKey: string): ImageOcrArtifact | null {
+    const row = this.database
+      .prepare('SELECT * FROM image_ocr_artifacts WHERE artifact_key = ?')
+      .get(artifactKey) as Record<string, unknown> | undefined
+    return row ? artifactFromRow(row) : null
+  }
+
+  putArtifact(artifact: ImageOcrArtifact): void {
+    if (artifact.accountId !== this.accountId) {
+      throw new Error('Image OCR artifact account does not match database')
+    }
+    const existing = this.getArtifact(artifact.artifactKey)
+    this.database
+      .prepare(
+        `INSERT INTO image_ocr_artifacts (
+          artifact_key, account_id, image_identity, state, text, char_count,
+          engine, platform, runtime_version, language, error_code, created_at, updated_at
+        ) VALUES (?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?)
+        ON CONFLICT(artifact_key) DO UPDATE SET
+          state = excluded.state,
+          text = excluded.text,
+          char_count = excluded.char_count,
+          runtime_version = excluded.runtime_version,
+          language = excluded.language,
+          error_code = excluded.error_code,
+          updated_at = excluded.updated_at`
+      )
+      .run(
+        artifact.artifactKey,
+        artifact.accountId,
+        artifact.imageIdentity,
+        artifact.state,
+        artifact.text,
+        artifact.charCount,
+        artifact.engine,
+        artifact.platform,
+        artifact.runtimeVersion,
+        artifact.language,
+        artifact.errorCode ?? null,
+        existing?.createdAt ?? artifact.createdAt,
+        artifact.updatedAt
+      )
+  }
+
+  // ----------------------------------------------------------------- bindings
+
+  /** 写入绑定；同一 OCR 结果可被多个会话/消息引用。 */
+  putBinding(binding: ImageOcrBinding): void {
+    if (binding.accountId !== this.accountId) {
+      throw new Error('Image OCR binding account does not match database')
+    }
+    this.database
+      .prepare(
+        `INSERT INTO image_ocr_bindings (
+          conversation_id, message_id, account_id, create_time, sender_id, sender_name,
+          image_identity, artifact_key, state, updated_at
+        ) VALUES (?, ?, ?, ?, ?, ?, ?, ?, ?, ?)
+        ON CONFLICT(conversation_id, message_id) DO UPDATE SET
+          create_time = excluded.create_time,
+          sender_id = excluded.sender_id,
+          sender_name = excluded.sender_name,
+          image_identity = excluded.image_identity,
+          artifact_key = excluded.artifact_key,
+          state = excluded.state,
+          updated_at = excluded.updated_at`
+      )
+      .run(
+        binding.conversationId,
+        binding.messageId,
+        binding.accountId,
+        binding.createTime,
+        binding.senderId ?? null,
+        binding.senderName ?? null,
+        binding.imageIdentity,
+        binding.artifactKey,
+        binding.state,
+        binding.updatedAt
+      )
+  }
+
+  /**
+   * 某会话的「消息 → OCR 文本」映射。
+   *
+   * 与语音的 `withVoiceTranscript` 同构：在**主进程**把派生文本贴到消息上，
+   * 再交给 Knowledge 索引，派生库不需要被 worker 打开。
+   */
+  getConversationOcr(
+    conversationId: string
+  ): Map<string, ConversationImageOcrEntry> {
+    const rows = asRows(
+      this.database
+        .prepare(
+          `SELECT b.message_id AS message_id, b.state AS binding_state,
+                  a.state AS artifact_state, a.text AS text
+           FROM image_ocr_bindings b
+           LEFT JOIN image_ocr_artifacts a ON a.artifact_key = b.artifact_key
+           WHERE b.conversation_id = ?`
+        )
+        .all(conversationId)
+    )
+    const result = new Map<string, ConversationImageOcrEntry>()
+    for (const row of rows) {
+      result.set(String(row.message_id), {
+        state: String(row.artifact_state || row.binding_state) as ImageOcrPersistedState,
+        text: String(row.text ?? '')
+      })
+    }
+    return result
+  }
+
+  // -------------------------------------------------------------- checkpoint
+
+  /**
+   * 已持久化的图片消息总数统计。
+   *
+   * 必须落盘：派生库只知道自己**处理过**什么，不知道源数据里**一共**有多少图片。
+   * 一旦把这个 total 只放在内存里，应用重启后 coverage 就会退化成
+   * 「processed / processed」→ 把 30% 的部分索引谎报成 100% 完整覆盖。
+   */
+  readCountedTotal(): { total: number; countedAt: number; complete: boolean } | null {
+    const total = this.readMeta('total_image_messages')
+    const countedAt = this.readMeta('total_image_counted_at')
+    if (total === null || countedAt === null) return null
+    const parsedTotal = Number(total)
+    const parsedCountedAt = Number(countedAt)
+    if (!Number.isFinite(parsedTotal) || !Number.isFinite(parsedCountedAt)) return null
+    return {
+      total: parsedTotal,
+      countedAt: parsedCountedAt,
+      // 统计时若有会话没数上（数据库不支持该统计），分母就是偏小的 →
+      // 绝不能据此声称"已覆盖全部"，否则少数的那些会话会被静默算进"已覆盖"。
+      complete: this.readMeta('total_image_messages_complete') === '1'
+    }
+  }
+
+  writeCountedTotal(input: { total: number; countedAt: number; complete: boolean }): void {
+    this.writeMeta('total_image_messages', String(input.total))
+    this.writeMeta('total_image_counted_at', String(input.countedAt))
+    this.writeMeta('total_image_messages_complete', input.complete ? '1' : '0')
+  }
+
+  readScanState(): Map<
+    string,
+    { state: string; imageTotal: number; processed: number; maxLocalId: number }
+  > {
+    const rows = asRows(
+      this.database
+        .prepare(
+          'SELECT conversation_id, state, image_total, image_processed, image_max_local_id FROM image_ocr_scan_state'
+        )
+        .all()
+    )
+    const map = new Map<
+      string,
+      { state: string; imageTotal: number; processed: number; maxLocalId: number }
+    >()
+    for (const row of rows) {
+      map.set(String(row.conversation_id), {
+        state: String(row.state),
+        imageTotal: Number(row.image_total ?? 0),
+        processed: Number(row.image_processed ?? 0),
+        maxLocalId: Number(row.image_max_local_id ?? 0)
+      })
+    }
+    return map
+  }
+
+  writeScanState(input: {
+    conversationId: string
+    state: 'done' | 'partial'
+    imageTotal: number
+    imageProcessed: number
+    /** 本会话图片消息的最大插入序（增量水位）。 */
+    maxLocalId: number
+  }): void {
+    this.database
+      .prepare(
+        `INSERT INTO image_ocr_scan_state (
+          conversation_id, account_id, state, image_total, image_processed,
+          image_max_local_id, updated_at
+        ) VALUES (?, ?, ?, ?, ?, ?, ?)
+        ON CONFLICT(conversation_id) DO UPDATE SET
+          state = excluded.state,
+          image_total = excluded.image_total,
+          image_processed = excluded.image_processed,
+          image_max_local_id = excluded.image_max_local_id,
+          updated_at = excluded.updated_at`
+      )
+      .run(
+        input.conversationId,
+        this.accountId,
+        input.state,
+        input.imageTotal,
+        input.imageProcessed,
+        input.maxLocalId,
+        Date.now()
+      )
+  }
+
+  // ------------------------------------------------------------------ 统计
+
+  /**
+   * 有 OCR 派生绑定的会话集合。
+   *
+   * 清理时**必须**先拿到它：OCR 文本早已被灌进 Knowledge 的 chunks / FTS，
+   * 只删派生病不会让那些派生文字失效 —— 用户仍会从旧索引里搜到图片里的文字。
+   */
+  conversationIdsWithOcr(): string[] {
+    const rows = asRows(
+      this.database.prepare('SELECT DISTINCT conversation_id FROM image_ocr_bindings').all()
+    )
+    return rows.map((row) => String(row.conversation_id))
+  }
+
+  /**
+   * **有 OCR 派生文本**（artifact 里 char_count > 0）的会话集合。
+   *
+   * 派生索引修复只需要重建它们：只有这些会话的 Knowledge 里"应该"存在图片派生文字。
+   * 全是 `empty` 的会话本来就没有派生文字可修，重建它们只是白读一遍 WCDB。
+   */
+  conversationIdsWithIndexedOcr(): string[] {
+    const rows = asRows(
+      this.database
+        .prepare(
+          `SELECT DISTINCT b.conversation_id AS conversation_id
+           FROM image_ocr_bindings b
+           JOIN image_ocr_artifacts a ON a.artifact_key = b.artifact_key
+           WHERE a.char_count > 0`
+        )
+        .all()
+    )
+    return rows.map((row) => String(row.conversation_id))
+  }
+
+  /**
+   * 重置指定状态的失败记录，让它们可以被下一轮 pass 重新处理。
+   *
+   * 用途：**代码修好后**，把上一次 bug 造成的假失败（例如整批 `decrypt_failed`）
+   * 变成可重试状态，而不是要求用户删掉整个派生库 —— 那会连已经成功的记录一起丢掉。
+   *
+   * 三件事一起做，缺一不可：
+   * 1. 删掉这些失败绑定；
+   * 2. 删掉它们所在会话的 checkpoint —— 否则 pass 会以"该会话已完成"直接跳过，
+   *    表现为"点了重试但什么都没发生"；
+   * 3. 删掉因此变成孤儿的 artifact（**没有任何绑定再引用的**才删，成功记录一条不动）。
+   */
+  resetFailures(states: ImageOcrPersistedState[]): number {
+    if (!states.length) return 0
+    const placeholders = states.map(() => '?').join(', ')
+    const affected = asRows(
+      this.database
+        .prepare(
+          `SELECT DISTINCT conversation_id FROM image_ocr_bindings WHERE state IN (${placeholders})`
+        )
+        .all(...states)
+    ).map((row) => String(row.conversation_id))
+    const artifactKeys = asRows(
+      this.database
+        .prepare(
+          `SELECT DISTINCT artifact_key FROM image_ocr_bindings WHERE state IN (${placeholders})`
+        )
+        .all(...states)
+    ).map((row) => String(row.artifact_key))
+
+    const info = this.database
+      .prepare(`DELETE FROM image_ocr_bindings WHERE state IN (${placeholders})`)
+      .run(...states)
+
+    const clearScan = this.database.prepare(
+      'DELETE FROM image_ocr_scan_state WHERE conversation_id = ?'
+    )
+    for (const conversationId of affected) clearScan.run(conversationId)
+
+    const dropOrphan = this.database.prepare(
+      `DELETE FROM image_ocr_artifacts
+        WHERE artifact_key = ?
+          AND NOT EXISTS (SELECT 1 FROM image_ocr_bindings b WHERE b.artifact_key = ?)`
+    )
+    for (const artifactKey of artifactKeys) dropOrphan.run(artifactKey, artifactKey)
+
+    return Number(info.changes ?? 0)
+  }
+
+  /** 按状态聚合绑定数 —— 覆盖度与进度都从这里取，保证与库内真实一致。 */
+  countByState(): Record<string, number> {    const rows = asRows(
+      this.database
+        .prepare('SELECT state, COUNT(*) AS total FROM image_ocr_bindings GROUP BY state')
+        .all()
+    )
+    const counts: Record<string, number> = {}
+    for (const row of rows) counts[String(row.state)] = Number(row.total ?? 0)
+    return counts
+  }
+
+  storageStats(): ImageTextIndexStorageStats {
+    const counts = this.countByState()
+    const textRow = this.database
+      .prepare(
+        "SELECT COUNT(*) AS total FROM image_ocr_artifacts WHERE state = 'indexed' AND length(text) > 0"
+      )
+      .get() as Record<string, unknown> | undefined
+    const updatedRow = this.database
+      .prepare('SELECT MAX(updated_at) AS latest FROM image_ocr_bindings')
+      .get() as Record<string, unknown> | undefined
+    let totalBytes = 0
+    for (const suffix of ['', '-wal', '-shm']) {
+      try {
+        totalBytes += statSync(`${this.databasePath}${suffix}`).size
+      } catch {
+        // 文件可能尚未创建；忽略。
+      }
+    }
+    const latest = updatedRow?.latest
+    return {
+      indexedImages: counts['indexed'] ?? 0,
+      ocrTextCount: Number(textRow?.total ?? 0),
+      totalBytes,
+      updatedAt: latest === null || latest === undefined ? null : Number(latest)
+    }
+  }
+
+  /** 清空全部派生数据（表级清空；文件级删除由 service 负责）。 */
+  clearAll(): void {
+    this.database.exec(`
+      DELETE FROM image_ocr_bindings;
+      DELETE FROM image_ocr_artifacts;
+      DELETE FROM image_ocr_scan_state;
+      DELETE FROM image_ocr_meta WHERE key IN (
+        'total_image_messages',
+        'total_image_counted_at',
+        'total_image_messages_complete'
+      );
+    `)
+  }
+
+  /**
+   * 清空并重置检查点。
+   *
+   * 注意：必须同时清 `scan_state`，否则清理后再次索引会因为「会话已完成」
+   * 而直接跳过 —— UI 会停在「未建立」但实际再也不跑。
+   */
+  clearDerivedData(): void {
+    this.clearAll()
+  }
+
+  close(): void {
+    try {
+      // 先折叠 WAL 再关连接：否则 -wal / -shm 可能仍被持有，
+      // Windows 上会导致后续 rmSync 静默失败（"清理成功"但文件还在）。
+      this.database.exec('PRAGMA wal_checkpoint(TRUNCATE);')
+    } catch {
+      // 库可能已经处于不可写状态；关闭仍然要做。
+    }
+    try {
+      this.database.close()
+    } catch {
+      // best effort
+    }
+  }
+}
diff --git a/src/main/services/local-query-api-service.ts b/src/main/services/local-query-api-service.ts
index 015361b..156e7a2 100644
--- a/src/main/services/local-query-api-service.ts
+++ b/src/main/services/local-query-api-service.ts
@@ -1,5 +1,6 @@
 import { listContactsAsync, listMessagesAsync, isReady, type FormattedContact, type FormattedMessage } from './chat-service'
 import { resolveContact } from './contact-resolution-service'
+import { sourceMessageId } from '../knowledge/message-identity'
 import type { KnowledgeSearchService } from '../knowledge/knowledge-search-service'
 import { inferAiSearchTimeRange } from '../../shared/ai-search'
 import { KNOWLEDGE_FRESHNESS_TOLERANCE_MS } from '../../shared/knowledge'
@@ -13,6 +14,7 @@ import type {
   ResolvedCorpusScope,
   ResolvedTimeRange,
   QueryIndexCoverage,
+  QueryImageTextCoverage,
   QuerySearchTimings,
   QueryMessagesRequest,
   SearchMessagesRequest,
@@ -26,6 +28,12 @@ import {
   decodeMessageRef as fromRef,
   normalizeMessageIdentity
 } from '../../shared/local-query-api'
+import {
+  describeImageTextCoverage,
+  imageTextCoverageState,
+  type ImageTextIndexCoverage
+} from '../../shared/image-text-index'
+import { toEvidenceDisplayText } from '../../shared/knowledge'
 
 const LIMIT_MAX = 200
 const CONTEXT_MAX = 50
@@ -112,6 +120,47 @@ function buildIndexCoverage(
   }
 }
 
+/**
+ * 图片文字索引未完成时，必须附加的零结果诚实性约束。
+ *
+ * 图片 OCR 是**独立的**覆盖维度：它可能是"未建立"或"只做了 30%"。
+ * 此时 0 条图片证据只是**索引缺口**，不是**事实空缺**。
+ */
+const IMAGE_OCR_ZERO_RESULT_CAUTION =
+  '涉及图片、截图、海报里的文字的问题，当前不能因为没搜到就回答"没有"。'
+
+/**
+ * 图片文字索引覆盖度 → 可直接引用的结论句。
+ *
+ * 与 `buildIndexCoverage` 同思路：只给结构化数字，模型会自己换算、甚至反过来
+ * 宣称"覆盖完整"。这里由 Engine 给出结论句，模型只需引用。
+ */
+export function buildImageOcrCoverage(
+  coverage: ImageTextIndexCoverage | null
+): QueryImageTextCoverage | undefined {
+  if (!coverage) return undefined
+  const state = imageTextCoverageState(coverage)
+  const countedNote = coverage.countedAt
+    ? `（图片数量统计于 ${formatLocalMinute(coverage.countedAt)}）`
+    : ''
+  const base = describeImageTextCoverage(coverage)
+  return {
+    state,
+    totalImageMessages: coverage.totalImageMessages,
+    processed: coverage.processed,
+    indexed: coverage.indexed,
+    empty: coverage.empty,
+    missing: coverage.missing,
+    failed: coverage.failed,
+    pending: coverage.pending,
+    ...(coverage.countedAt ? { countedAtLabel: formatLocalMinute(coverage.countedAt) } : {}),
+    summary:
+      state === 'complete'
+        ? `${base}${countedNote}`
+        : `${base}${countedNote}${IMAGE_OCR_ZERO_RESULT_CAUTION}`
+  }
+}
+
 const KIND_LABELS: Record<QueryMessageType, string> = {
   text: '文本',
   image: '图片',
@@ -149,7 +198,19 @@ function resolvedTimeRange(input: QueryTimeRange, now = new Date()): ResolvedTim
   const range = inferAiSearchTimeRange(phrase[input.kind], map[input.kind], now)
   return { kind: input.kind, startTime: range.startTime, endTime: range.endTime, label: range.label }
 }
-function toQueryMessage(conversationId: string, message: FormattedMessage, target: FormattedContact): QueryMessage {
+/**
+ * 一条消息的展示形态。
+ *
+ * `imageOcr` 是可选的**派生文本**（来自本地图片文字索引，只读、不触发 OCR）。
+ * 图片消息的正文永远是空的 —— 识别出的文字必须走独立字段，
+ * 否则"图片里的文字"会被伪装成"群友发的文字消息"。
+ */
+function toQueryMessage(
+  conversationId: string,
+  message: FormattedMessage,
+  target: FormattedContact,
+  imageOcr?: { state: string; text: string }
+): QueryMessage {
   const kind = kindOf(message)
   const content = message.contentData
   const attachment =
@@ -163,7 +224,16 @@ function toQueryMessage(conversationId: string, message: FormattedMessage, targe
             ? { kind: 'file' as const, name: message.exportMediaName || (content?.type === 'share' ? content.title : undefined), url: content?.type === 'share' ? content.url : undefined }
             : undefined
   const text = message.content?.trim() || message.voiceTranscript?.trim() || undefined
-  return { messageRef: toRef(conversationId, message.id), timestamp: (message.createTime || 0) * 1000, datetime: message.datetime, sender: message.isSender ? '我' : (message.name || target.m_nsNickName), direction: message.isSender ? 'to_target' : 'from_target', messageType: kind, sourceKind: kind, ...(attachment ? { attachment } : {}), ...(text ? { text } : {}) }
+  const derived = kind === 'image' ? imageOcr : undefined
+  const ocrText = derived && derived.state === 'indexed' ? derived.text.trim() : ''
+  const imageTextState: QueryMessage['imageTextState'] = !derived
+    ? 'not_indexed'
+    : ocrText
+      ? 'indexed'
+      : derived.state === 'empty'
+        ? 'empty'
+        : 'not_indexed'
+  return { messageRef: toRef(conversationId, message.id), timestamp: (message.createTime || 0) * 1000, datetime: message.datetime, sender: message.isSender ? '我' : (message.name || target.m_nsNickName), direction: message.isSender ? 'to_target' : 'from_target', messageType: kind, sourceKind: kind, ...(attachment ? { attachment } : {}), ...(text ? { text } : {}), ...(ocrText ? { imageOcrText: ocrText, derivedSource: 'image_ocr' as const } : {}), ...(kind === 'image' ? { imageTextState } : {}) }
 }
 
 /**
@@ -216,7 +286,49 @@ function outsideScopeError(scope: ResolvedCorpusScope, actual: string): { status
 }
 
 export class LocalQueryApiService {
-  constructor(private readonly knowledge?: KnowledgeSearchService, private readonly nowProvider: () => Date = () => new Date()) {}
+  /**
+   * 图片文字索引覆盖度提供者（同步、只读）。
+   *
+   * 刻意不在 Knowledge worker 里算：OCR 派生库（`image-text-index.sqlite`）与
+   * `knowledge.sqlite` 物理分离，worker 不该为了一个覆盖度数字去开它。
+   */
+  private imageTextCoverage: () => ImageTextIndexCoverage | null = () => null
+
+  /**
+   * 单条图片消息的 OCR 派生文本提供者（同步、只读）。
+   *
+   * L4（查询层）**只读** L1（OCR artifact）—— 这里绝不允许触发 OCR、解密或读原图。
+   * 之前 `query_messages` 缺这一环，导致"图片已经识别出文字"这件事在精确读消息
+   * 这条路径上完全不可见：模型只拿到一个空的 `attachment`，于是把"索引缺口"
+   * 说成"图片里没有文字"，甚至反过来建议用户去建立已经建好的索引。
+   */
+  private imageOcrEntry:
+    | ((conversationId: string, messageId: string) => { state: string; text: string } | undefined)
+    | undefined
+
+  constructor(
+    private readonly knowledge?: KnowledgeSearchService,
+    private readonly nowProvider: () => Date = () => new Date()
+  ) {}
+
+  /**
+   * 注入图片文字索引覆盖度提供者。
+   *
+   * 用 setter 而不是构造参数：避免给第二个带默认值的参数写 `undefined` 占位，
+   * 也让测试可以直接注入假的覆盖度。
+   */
+  setImageTextCoverageProvider(provider: () => ImageTextIndexCoverage | null): void {
+    this.imageTextCoverage = provider
+  }
+
+  /** 注入单条图片消息的 OCR 派生文本解析器（只读；见 `imageOcrEntry` 的约束）。 */
+  setImageOcrEntryProvider(
+    provider:
+      | ((conversationId: string, messageId: string) => { state: string; text: string } | undefined)
+      | undefined
+  ): void {
+    this.imageOcrEntry = provider
+  }
   capabilities(): QueryCapabilitiesResponse {
     return { version: 1, tools: { query_messages: { operation: '读取指定联系人的确定性消息', directions: ['any', 'from_target', 'to_target'], messageTypes: kinds, timeRanges: ['all', 'today', 'yesterday', 'this_week', 'last_7_days', 'this_month', 'previous_month', 'this_year', 'previous_year', 'absolute'], limitMax: LIMIT_MAX }, search_messages: { operation: '受限 Knowledge 关键词检索', timeRanges: ['all', 'today', 'yesterday', 'this_week', 'last_7_days', 'this_month', 'previous_month', 'this_year', 'previous_year', 'absolute'], limitMax: LIMIT_MAX }, message_context: { operation: '读取消息前后文', timeRanges: ['all'], limitMax: CONTEXT_MAX }, conversation_overview: { operation: '按会话时间片提取概览证据', timeRanges: ['all', 'today', 'yesterday', 'this_week', 'last_7_days', 'this_month', 'previous_month', 'this_year', 'previous_year', 'absolute'], limitMax: LIMIT_MAX } } }
   }
@@ -282,7 +394,18 @@ export class LocalQueryApiService {
     const raw = await listMessagesAsync(contact.md5, range.startTime, range.endTime)
     const direction = request.direction || 'any'; const allowed = new Set(request.messageTypes || kinds)
     const filtered = raw.filter((message) => !(request.excludeSystem !== false && kindOf(message) === 'system')).filter((message) => allowed.has(kindOf(message))).filter((message) => direction === 'any' || (direction === 'to_target' ? message.isSender : !message.isSender)).sort((a, b) => ((a.createTime || 0) - (b.createTime || 0)) * ((request.order || 'asc') === 'asc' ? 1 : -1)).slice(0, Math.min(LIMIT_MAX, Math.max(1, request.limit || 20)))
-    return { status: 'completed' as const, target: contactView(contact), query: { direction, messageTypes: request.messageTypes || [], order: request.order || 'asc', limit: Math.min(LIMIT_MAX, Math.max(1, request.limit || 20)), excludeSystem: request.excludeSystem !== false, resolvedTimeRange: range }, coverage: { state: 'complete' as const }, returnedCount: filtered.length, messages: filtered.map((message) => toQueryMessage(contact.md5, message, contact)), scope: corpus.scope }
+    // 图片 OCR 派生文本：L4 只读 L1，**不触发 OCR / 解密 / 读原图**。
+    // 键必须用 `sourceMessageId(message)`（binding 主键就是它），不能用裸 `message.id`，
+    // 否则 `local:` 前缀会让查表静默失配 —— 与 Knowledge 用同一条身份规则。
+    const messages = filtered.map((message) => {
+      const ocr =
+        kindOf(message) === 'image'
+          ? this.imageOcrEntry?.(contact.md5, sourceMessageId(message))
+          : undefined
+      return toQueryMessage(contact.md5, message, contact, ocr)
+    })
+    const imageOcrCoverage = buildImageOcrCoverage(this.imageTextCoverage())
+    return { status: 'completed' as const, target: contactView(contact), query: { direction, messageTypes: request.messageTypes || [], order: request.order || 'asc', limit: Math.min(LIMIT_MAX, Math.max(1, request.limit || 20)), excludeSystem: request.excludeSystem !== false, resolvedTimeRange: range }, coverage: { state: 'complete' as const }, returnedCount: filtered.length, messages, scope: corpus.scope, ...(imageOcrCoverage ? { imageOcrCoverage } : {}) }
   }
   async search(request: SearchMessagesRequest) {
     const requestStartedAt = Date.now()
@@ -359,6 +482,8 @@ export class LocalQueryApiService {
 
     const covered = indexCovers(found.indexLatestAt, requestedEnd, found.sourceLatestAt)
     const indexCoverage = buildIndexCoverage(found.indexLatestAt, found.sourceLatestAt, covered)
+    // 图片文字索引是**独立覆盖维度**：文字索引再完整也不代表图片里的文字搜得到。
+    const imageOcrCoverage = buildImageOcrCoverage(this.imageTextCoverage())
     const timings: QuerySearchTimings = {
       totalMs: Date.now() - requestStartedAt,
       scopeMs,
@@ -381,6 +506,7 @@ export class LocalQueryApiService {
       sourceLatestAt: found.sourceLatestAt,
       freshness: { catchUp: freshness.catchUp },
       ...(indexCoverage ? { indexCoverage } : {}),
+      ...(imageOcrCoverage ? { imageOcrCoverage } : {}),
       timings
     }
   }
@@ -454,7 +580,11 @@ export class LocalQueryApiService {
               timestamp: item.timestamp,
               sender: item.sender,
               sourceKind: item.sourceKind,
-              text: item.text,
+              // 兜底再剥一次：不管 Knowledge 侧哪条检索路径产出的文本，
+              // 面向用户与模型的都不允许出现 `图片文字：` 这类引擎内部标签。
+              text: toEvidenceDisplayText(item.text),
+              ...(item.derivedSource ? { derivedSource: item.derivedSource } : {}),
+              ...(item.imageOcrText ? { imageOcrText: item.imageOcrText } : {}),
               conversationName: owner ? contactView(owner).displayName : undefined,
               conversationType: owner?.type
             } satisfies QueryEvidenceItem
@@ -592,6 +722,7 @@ export class LocalQueryApiService {
     const truncated = raw.length > OVERVIEW_SOURCE_CAP
     const evidence = selectTemporalCoverageEvidence(contact, messages, OVERVIEW_EVIDENCE_TARGET)
     const state: 'complete' | 'partial' = truncated ? 'partial' : 'complete'
+    const imageOcrCoverage = buildImageOcrCoverage(this.imageTextCoverage())
     return {
       status: 'completed' as const,
       target: contactView(contact),
@@ -603,6 +734,7 @@ export class LocalQueryApiService {
       selection: { mode: 'temporal_coverage' as const, selectedEvidenceCount: evidence.length, sampled: truncated || evidence.length < messages.length },
       evidence,
       scope: corpus.scope,
+      ...(imageOcrCoverage ? { imageOcrCoverage } : {}),
       origin: 'wcdb' as const
     }
   }
diff --git a/src/main/services/query-agent-service.ts b/src/main/services/query-agent-service.ts
index ece0e4c..227c262 100644
--- a/src/main/services/query-agent-service.ts
+++ b/src/main/services/query-agent-service.ts
@@ -106,6 +106,17 @@ export interface QueryAgentTraceItem {
    * 会剥离）。用途：把不透明的 Tool 总耗时拆成 scope / freshness / 每个 probe / 合并 / 证据补全。
    */
   searchTimings?: QuerySearchTimings
+  /**
+   * 本次 Tool Result 里携带 OCR 派生文本的图片消息/证据条数（诊断用，不进模型上下文）。
+   *
+   * 存在的意义是让"图片已经识别出文字、但模型没拿到"这类**链路断点**可以被直接观测：
+   * 真机上曾经出现过 `query_messages` 返回了图片消息却只带 `attachment`、
+   * 模型因此回答"没有取得 OCR 文字"。当时从回答文本无法判断是"索引没建"还是"没接上"，
+   * 因为这两件事在日志里长得一模一样。有了这个数字就能一眼分开。
+   */
+  imageOcrTextCount?: number
+  /** 本次 Tool Result 里图片文字索引的覆盖度状态（`not_built` / `partial` / `complete` / `failed`）。 */
+  imageOcrCoverageState?: string
 }
 
 export interface QueryAgentModelCallDiagnostic {
@@ -207,6 +218,12 @@ const SYSTEM_PROMPT = `你是 TraceMemo 的本地聊天查询助手，只能使
 规划原则：
 - 先判断问题需要哪种证据，再调用最少的 Tool。每次收到 Tool Result 后都判断“当前 Evidence 是否已经足以给出有边界的回答”；足够就立即回答，不为追求绝对完整继续调查。
 - query_messages 是精确事实查询，适用于能用联系人、时间、方向、消息类型、顺序等结构条件表达的问题。earliest/latest 等时间边界也是结构条件，必须使用 order 与 limit 精确查询，不能使用抽样 overview。每次调用都必须如实声明 temporalBasis。结果已经回答问题时，不要追加 conversation_overview。
+方向（direction）必须按**说话人是谁**来定，不要按语序猜：
+- direction 的参照物是“目标会话”：to_target = **我发出**的（说话人是我自己），from_target = **对方发来**的。没有 other 取值，拿不准就用 any。
+- 说话人是我 → to_target：“我给张三发了什么”“我发给张三的”“我发给他的文件”“我之前给他发过什么”“我发出去的图片”“我在这个群里发过什么”。
+- 说话人是对方 → from_target：“张三给我发了什么”“他之前给我的图片”“张三发给我的文件”。
+- **不许**因为“我”出现在句首就选 from_target；也不要凭昵称是否叫“我”来判断说话人，自我身份以消息自身的发送者标记为准。
+- 一旦某次 query_messages 返回 0 条，先回头核对 direction 是否与问题的说话人**冲突**；冲突就属于允许的 substantively different retry，必须直接换方向再查一次，**不要**问用户“是不是方向搞错了/要不要换个方向”，用户已经把话说清楚了。
 - 需要绝对时间范围时，startTime/endTime 必须使用带时区偏移的 ISO-8601 字符串（例如 2026-08-01T00:00:00+08:00 或 2026-07-31T16:00:00Z）。不要传 epoch 数字，也不要传没有时区的裸本地时间。
 - search_messages 是关键词检索，适用于结构条件无法确定答案的问题。queries 的每一项都是一次独立的字面检索：一项只放一个简短关键词，不要把多个近义词或整句话塞进同一项。首次最多 4 项。检索到 Evidence 后直接判断；只有本次完全没有 Evidence 时，才允许再检索一次，且每一项都必须与上一次实质不同。
 - conversation_overview 只用于真正需要理解一个时间范围内整体聊了什么、主要话题或整体互动的 broad summary。它返回 temporal coverage sample，不代表完整聊天，也不是检索不足时的默认 fallback。
@@ -219,6 +236,20 @@ const SYSTEM_PROMPT = `你是 TraceMemo 的本地聊天查询助手，只能使
 - indexCoverage.covered 为 false 时，说明这段时间还没进索引：此时即使结果为 0 也只能说"索引尚未覆盖这段时间，暂时无法确认"，**绝不能**说成"没有"。必须如实引用结论里的索引更新时间。
 - 已经检索到 Evidence 时，只有当这个覆盖边界真的会影响结论时才补一句说明，不要机械附加警告。
 - 只有 coverage.state 为 complete（indexCoverage.covered 为 true）且结果为 0，才可以下"没有找到"的结论。不要自己把 partial 说成 complete。
+图片文字索引：search_messages 的 imageOcrCoverage 是**独立于文字索引**的覆盖维度，只针对“图片里的文字”（截图、报价图、公告截图、海报）。规则：
+- 文字消息索引完整**不代表**图片里的文字搜得到。不要把这两个维度混着说。
+- 问题涉及图片里的文字、而 imageOcrCoverage.state 不是 complete 时：即使图片证据为 0，也**绝不能**回答“没有”或“没找到”。必须如实引用 imageOcrCoverage.summary，说明图片文字索引尚未完成、当前无法确认全部历史图片。
+- imageOcrCoverage.state 为 not_built 时，明确告诉用户图片文字索引还没建立，图片里的文字目前搜不到，并提示可以在「问问微信」里建立。
+- 只有 imageOcrCoverage.state 为 complete 且图片证据为 0，才可以下“没有找到”的结论。
+图片消息的文字（query_messages 与 search_messages 都适用）：
+- 图片消息可能带 imageOcrText / derivedSource=image_ocr —— 那是**这张图片里识别出的文字**（本地 OCR 派生），可以直接用它回答“图片里写了什么”。问法可能是“我今早发的那张图片里写了什么”“那张 ChatGPT 价格截图是什么内容”。
+- imageOcrText 是派生内容，**证据永远是那条原始图片消息**：messageRef、sender、conversation、时间都只能用原始图片消息的。描述时说“图片里的文字是…”，**不许**把它说成某人发的一条文字消息，**不许**为了它编造任何不存在的消息。
+- imageTextState 是**结构化事实**，三种取值含义不同，不要互相替代：
+  - indexed：已识别出文字（同时有 imageOcrText）。
+  - empty：本地识别过，这张图里确实没有文字。此时**只能**回答图片本身，**绝不许**根据 OCR 去猜人物、场景、物体或表情包含义（OCR 不是看图，没有 Vision 能力就不要假装有）。
+  - not_indexed：这条图片还没进图片文字索引。**不许**把“还没索引”说成“图片里没有文字”；若 imageOcrCoverage 不是 complete，必须说明当前无法确认。
+- 图片文字索引状态一律以 Tool Result 的结构化字段为准。**不要**在回答里凭空建议“可以先建立图片文字索引再查”——只有 imageOcrCoverage.state 确实是 not_built 时才可以这么说。
+- 区分「图片里确实没有文字」（OCR 结果为空，属于已处理的正常终态）与「图片还没被索引」（覆盖缺口）：前者是事实，后者不能当成事实。
 缺少必要信息时用自然语言澄清；超出工具能力时说明不能可靠完成，并给出当前工具可以执行的替代方向。`
 
 function toolDefinitions(): AIChatToolDefinition[] {
@@ -545,7 +576,7 @@ function retryNote(name: string, result: QueryAgentToolResult, state: ZeroResult
   if (result.status !== 'completed') return undefined
   const counts = resultCount(result)
   if (name === 'search_messages' && !counts.evidenceCount && state.searchAttempts <= ZERO_RESULT_RETRY_LIMIT) return '本次检索没有任何 Evidence。允许再执行一次 search_messages，但每一项都必须与上一次实质不同；完全相同的检索会被拒绝。'
-  if (name === 'query_messages' && counts.resultCount === 0 && !result.fallbackLookup && state.queryAttempts <= ZERO_RESULT_RETRY_LIMIT) return '本次精确查询返回 0 条。允许再执行一次 query_messages，用于放宽 direction 或 messageTypes 等非时间条件；改变时间范围会被拒绝。'
+  if (name === 'query_messages' && counts.resultCount === 0 && !result.fallbackLookup && state.queryAttempts <= ZERO_RESULT_RETRY_LIMIT) return '本次精确查询返回 0 条。只允许放宽 direction 或 messageTypes 等非时间条件（改变时间范围会被拒绝）。**特别注意方向选反这种情况**：如果问题是“我给 X 发 / 我发给 X 的”，而本次用的是 from_target（对方发来），那是方向选反了 —— 直接改用 to_target 重查一次，这属于允许的实质不同重试。不要因为有 0 条就收尾，也不要问用户“是不是方向搞错了 / 要不要换个方向”，用户已经把说话人讲清楚了。'
   return undefined
 }
 
@@ -583,10 +614,52 @@ function messageRecordForModel(value: unknown): unknown {
   return record.messageType || !record.sourceKind ? record : { ...record, messageType: record.sourceKind }
 }
 
-function toolResultForModel(name: string, result: QueryAgentToolResult, callsUsed: number, nextTools: AIChatToolDefinition[], note?: string): QueryAgentToolResult {
-  const visible: QueryAgentToolResult = { ...result }
+/**
+ * 从 Tool Result 里读出图片 OCR 的两条**结构化事实**（诊断 / 日志用）。
+ *
+ * 只看字段存在与否与数量，**不读文本内容**：排查链路断点不需要正文，
+ * 日志里也不该多留一份聊天内容。
+ */
+function imageOcrDiagnostics(result: QueryAgentToolResult): {
+  imageOcrTextCount?: number
+  imageOcrCoverageState?: string
+} {
+  let count = 0
+  const collect = (value: unknown): void => {
+    if (!Array.isArray(value)) return
+    for (const item of value) {
+      if (!item || typeof item !== 'object' || Array.isArray(item)) continue
+      const text = (item as Record<string, unknown>).imageOcrText
+      if (typeof text === 'string' && text.trim()) count += 1
+    }
+  }
+  collect(result.messages)
+  collect(result.evidence)
+  const coverage = result.imageOcrCoverage
+  const state =
+    coverage && typeof coverage === 'object' && !Array.isArray(coverage)
+      ? (coverage as Record<string, unknown>).state
+      : undefined
+  return {
+    ...(count > 0 ? { imageOcrTextCount: count } : {}),
+    ...(typeof state === 'string' ? { imageOcrCoverageState: state } : {})
+  }
+}
+
+function toolResultForModel(name: string, result: QueryAgentToolResult, callsUsed: number, nextTools: AIChatToolDefinition[], note?: string): QueryAgentToolResult {  const visible: QueryAgentToolResult = { ...result }
   if (Array.isArray(result.messages)) visible.messages = result.messages.map(messageRecordForModel)
-  if (Array.isArray(result.evidence)) visible.evidence = result.evidence.map(messageRecordForModel)
+  if (Array.isArray(result.evidence)) {
+    visible.evidence = result.evidence.map((item) => {
+      const record = messageRecordForModel(item)
+      if (!record || typeof record !== 'object' || Array.isArray(record)) return record
+      // `imageOcrText` 是给 Evidence UI 做"命中解释"的片段；它的内容已经在 `text` 里，
+      // 再原样带一份进模型上下文是纯重复。模型侧保留 `derivedSource` 这个语义标记即可，
+      // 由此知道"这条命中的是图片里的文字"。
+      const trimmed = { ...(record as Record<string, unknown>) }
+      delete trimmed.imageOcrText
+      return trimmed
+    })
+  }
   if (result.anchor) visible.anchor = messageRecordForModel(result.anchor)
   if (Array.isArray(result.before)) visible.before = result.before.map(messageRecordForModel)
   if (Array.isArray(result.after)) visible.after = result.after.map(messageRecordForModel)
@@ -616,7 +689,7 @@ function toolResultForModel(name: string, result: QueryAgentToolResult, callsUse
   return visible
 }
 
-function nextToolDefinitions(name: string, result: QueryAgentToolResult, state: ZeroResultRetryState, rangeWasAll = false): AIChatToolDefinition[] {
+function nextToolDefinitions(name: string, result: QueryAgentToolResult, state: ZeroResultRetryState): AIChatToolDefinition[] {
   // 重复重试已被拒绝，不再开放工具，避免用有限的 tool budget 反复试同一条件。
   if (result.constraint === 'duplicate_retry') return []
   if (result.status === 'invalid_tool_arguments') return toolDefinition(name)
@@ -631,10 +704,24 @@ function nextToolDefinitions(name: string, result: QueryAgentToolResult, state:
   if (name === 'query_messages') {
     // Host 已经自动执行过一次扩大查询：不再开放 retry，避免出现第三次查询。
     if (result.fallbackLookup) return []
-    // 已经查了全部历史且 0 结果：再换时间范围毫无意义（更窄只会更少）。
-    if (rangeWasAll && counts.resultCount === 0) return []
-    // 只有 0 结果才开放一次重试；有结果时保持原有 stopping。
-    return counts.resultCount === 0 && state.queryAttempts <= ZERO_RESULT_RETRY_LIMIT ? toolDefinition('query_messages') : []
+    /**
+     * 这里**不能**因为"时间范围已经是全部"就关掉重试。
+     *
+     * 原实现是 `if (rangeWasAll && resultCount === 0) return []`，依据是"时间不能再放宽了、
+     * 更窄只会更少"。但 0 结果的重试本来就不是为了改时间 —— 它是为了放宽
+     * **direction / messageTypes**：「我给 X 发了什么图片」被错判成 `from_target` 时，
+     * 换成 `to_target` 会从 0 条变成有结果。
+     *
+     * 这个守卫的后果正是真机那个回归：工具没发出去 → 第二次调用被
+     * `tool_availability` 拒掉 → 模型想改向也调不动 → 只能回头问用户"是不是方向搞错了"。
+     *
+     * 时间范围不可变由 `constraint_time_range_immutable` 单独把关，
+     * 完全相同的重试由 `duplicate_retry` 拦下，次数由 ZERO_RESULT_RETRY_LIMIT 限制，
+     * 所以这里放开是安全的。
+     */
+    return counts.resultCount === 0 && state.queryAttempts <= ZERO_RESULT_RETRY_LIMIT
+      ? toolDefinition('query_messages')
+      : []
   }
   return []
 }
@@ -772,6 +859,12 @@ class EvidenceCollector {
           ? { messageType: record.sourceKind }
           : {}),
       ...(typeof record.text === 'string' && record.text ? { text: record.text } : {}),
+      // 「靠图片里的文字命中」这个来源语义必须带到 UI：用户要能看出这条答案来自
+      // 图片 OCR，而不是群友真发了一条文字消息。messageRef 仍然指向原始图片消息。
+      ...(record.derivedSource === 'image_ocr' ? { derivedSource: 'image_ocr' as const } : {}),
+      ...(typeof record.imageOcrText === 'string' && record.imageOcrText
+        ? { imageOcrText: record.imageOcrText }
+        : {}),
       ...(attachmentView && Object.keys(attachmentView).length ? { attachment: attachmentView } : {}),
       source
     }
@@ -967,10 +1060,10 @@ export class QueryAgentService {
           rawTimings && typeof rawTimings === 'object' && !Array.isArray(rawTimings)
             ? (rawTimings as QuerySearchTimings)
             : undefined
-        result.traces.push({ toolName: call.name, input: sanitizeInput(traceInput), durationMs, status: completedToolResult.status, ...counts, ...(temporalBasis ? { temporalBasis } : {}), ...(autoFallback ? { autoFallback } : {}), ...(searchTimings ? { searchTimings } : {}) })
+        result.traces.push({ toolName: call.name, input: sanitizeInput(traceInput), durationMs, status: completedToolResult.status, ...counts, ...imageOcrDiagnostics(completedToolResult), ...(temporalBasis ? { temporalBasis } : {}), ...(autoFallback ? { autoFallback } : {}), ...(searchTimings ? { searchTimings } : {}) })
         const nextTools = completedToolResult.constraint === 'tool_availability'
           ? tools
-          : nextToolDefinitions(call.name, completedToolResult, retry, rangeKind(traceInput) === 'all')
+          : nextToolDefinitions(call.name, completedToolResult, retry)
         const note = retryNote(call.name, completedToolResult, retry)
         messages.push({ role: 'tool', tool_call_id: call.id, name: call.name, content: JSON.stringify(toolResultForModel(call.name, completedToolResult, result.toolCallCount, nextTools, note)) })
         tools = nextTools
diff --git a/src/main/wcdb4-client.ts b/src/main/wcdb4-client.ts
index f75a6c2..cbf9d27 100644
--- a/src/main/wcdb4-client.ts
+++ b/src/main/wcdb4-client.ts
@@ -6,6 +6,7 @@ import { createRequire } from 'module'
 import { createConnection, Socket } from 'net'
 import { getResourceRoots } from './resource-paths'
 import { wcdbDebugLog } from './wcdb-debug'
+import type { ImageMessageCountProbe } from '../shared/image-text-index'
 
 export interface Wcdb4Session {
   username: string
@@ -1232,11 +1233,15 @@ export class Wcdb4Client {
   }
 
   async countVoiceMessagesAsync(
-    username: string,
+    md5OrUsername: string,
     startTime?: number,
     endTime?: number
   ): Promise<number | null> {
     if (!this.wcdbGetMessageTableStats || !this.wcdbExecQuery) return null
+    // 与图片计数同因的修正：同一个 md5/username 混淆在这里也存在，
+    // 而且它更隐蔽 —— 匹配不到表时循环不执行，函数会**返回 0 而不是报错**。
+    const username = this.resolveMessageUsername(md5OrUsername)
+    if (!username) return null
 
     let tables: Wcdb4MessageStore[]
     try {
@@ -1276,6 +1281,203 @@ export class Wcdb4Client {
     return total
   }
 
+  /**
+   * 消息类型列的可能名字（按顺序探测，命中即用）。
+   *
+   * 为什么不能直接硬编码 `"local_type"`：`pickValue(row, [...别名])` 那套别名列表只作用于
+   * **已经读出来的行**；一旦把列名写进 WHERE，列名不同的库会当场抛错，再被 catch 吞成
+   * `null` —— 表现就是"检测到 0 张图片"。所以必须先探测真实列名。
+   */
+  private readonly messageTypeColumnCandidates = [
+    'local_type',
+    'localType',
+    'msg_type',
+    'msgType',
+    'message_type',
+    'messageType',
+    'type',
+    'WCDB_CT_local_type'
+  ]
+
+  /** 每个消息分片的真实类型列名；探测一次即缓存，避免每个会话都跑一次 PRAGMA。 */
+  private readonly messageTypeColumnCache = new Map<string, string | null>()
+
+  private resolveMessageTypeColumn(store: Wcdb4MessageStore): string | null {
+    const cacheKey = `${store.dbPath}\u0000${store.tableName}`
+    const cached = this.messageTypeColumnCache.get(cacheKey)
+    if (cached !== undefined) return cached
+    let resolved: string | null = null
+    try {
+      const columns = this.readMessageColumns(store).map((column) => column.name)
+      for (const candidate of this.messageTypeColumnCandidates) {
+        const hit = columns.find((name) => name.toLowerCase() === candidate.toLowerCase())
+        if (hit) {
+          resolved = hit
+          break
+        }
+      }
+    } catch {
+      resolved = null
+    }
+    this.messageTypeColumnCache.set(cacheKey, resolved)
+    return resolved
+  }
+
+  /**
+   * 把「会话 md5」解析成原生接口真正需要的 username。
+   *
+   * `contact.md5` 是 `md5(wxid)` 的**哈希**（见 chat-service 的 `dbRef.md5(user.m_nsUsrName)`），
+   * 而 `wcdbGetMessageTableStats` / `wcdbGetMessages` 这些原生接口要的是**原始 username**。
+   * 直接把 md5 当 username 传，原生侧匹配不到任何表 —— 表现为"未找到该会话的消息表"，
+   * 而按表统计的计数会静默变成 0。
+   *
+   * 既有读消息路径一直做了这层转换（`listSourceMessages` 里的 `getUsernameByMd5`），
+   * **统计/水位路径漏了**，所以这里统一补上。
+   *
+   * 解析不到时原样返回：调用方本来就传 username 的路径仍然可用。
+   */
+  private resolveMessageUsername(md5OrUsername: string): string {
+    const value = String(md5OrUsername || '').trim()
+    if (!value) return value
+    const bySession = this.getUsernameByMd5(value)
+    if (bySession) return bySession
+    // 有些群只以 `Chat_<md5>` 表存在、不在 session 列表里；退回按聊天表映射解析
+    // （与 wechat-db 的 `chatMd5ToUsername` 同一套依据）。
+    try {
+      const byChatTable = this.getChatTables().find((table) => table.name === `Chat_${value}`)
+      if (byChatTable?.db_number) return byChatTable.db_number
+    } catch {
+      // 映射不可用时退回原值。
+    }
+    return value
+  }
+
+  /** 图片消息的 WHERE 片段；`sinceMs` 用于只统计某个时间点之后的消息（测试小窗口）。 */
+  private imageMessageWhere(column: string, sinceMs?: number): string {
+    const clauses = [`(${this.quoteSqlIdentifier(column)} & 65535) = 3`]
+    // 微信的 create_time 是**秒**，调用方给的是毫秒。
+    if (sinceMs && Number.isFinite(sinceMs) && sinceMs > 0) {
+      clauses.push(`"create_time" >= ${Math.floor(sinceMs / 1000)}`)
+    }
+    return clauses.join(' AND ')
+  }
+
+  /**
+   * 统计图片消息条数。
+   *
+   * 与 `countVoiceMessagesAsync` 同构：纯 SQL COUNT，**不解密任何图片** ——
+   * 这是「点击索引前先告诉用户有多少张图片」能足够快的前提。
+   *
+   * 与语音版本的关键差别：这里**必须区分「0 张」与「统计失败」**。
+   * `count: null` 表示没数成，调用方绝不能把它当成 0。
+   */
+  async countImageMessagesAsync(
+    md5OrUsername: string,
+    sinceMs?: number
+  ): Promise<ImageMessageCountProbe> {
+    if (!this.wcdbGetMessageTableStats || !this.wcdbExecQuery) {
+      return { count: null, typeColumn: null, error: '当前数据服务不支持消息表统计' }
+    }
+    const username = this.resolveMessageUsername(md5OrUsername)
+    if (!username) {
+      return { count: null, typeColumn: null, error: '无法解析该会话的标识' }
+    }
+
+    let tables: Wcdb4MessageStore[]
+    try {
+      tables = await this.listMessageStoresAsync(username)
+    } catch {
+      return { count: null, typeColumn: null, error: '读取消息分片失败' }
+    }
+    if (!tables.length) {
+      return { count: null, typeColumn: null, error: '未找到该会话的消息表' }
+    }
+
+    let total = 0
+    let typeColumn: string | null = null
+    for (const table of tables) {
+      const column = this.resolveMessageTypeColumn(table)
+      if (!column) {
+        return { count: null, typeColumn: null, error: '消息表缺少可识别的消息类型列' }
+      }
+      if (!typeColumn) typeColumn = column
+      try {
+        const rows = await this.callJsonAsync<Record<string, unknown>[]>(
+          this.wcdbExecQuery as unknown as KoffiAsyncFunction,
+          'message',
+          table.dbPath,
+          `SELECT COUNT(*) AS "image_count" FROM ${this.quoteSqlIdentifier(table.tableName)} WHERE ${this.imageMessageWhere(column, sinceMs)}`
+        )
+        const value = Number(this.pickValue(rows[0] || {}, ['image_count', 'count', 'COUNT(*)']))
+        if (Number.isFinite(value)) total += value
+      } catch {
+        return { count: null, typeColumn: null, error: '图片消息统计查询失败' }
+      }
+    }
+    return { count: total, typeColumn }
+  }
+
+  /**
+   * 图片消息的增量水位：`count` + `max(local_id)`。
+   *
+   * 为什么不能只靠 `countImageMessagesAsync`：
+   * 图片总数相同**不代表**图片集合没变。撤回一张旧图 + 新增一张新图，count 不变，
+   * 但新图的 `local_id` 更大。只看 count 会静默跳过该会话，新图片永远搜不到。
+   *
+   * `local_id` 是 WCDB 每张消息表内的插入序（自增），所以：
+   * - 任何 append → `max_local_id` 严格变大；
+   * - 「删旧 + 增新」且总数不变 → `max_local_id` 也变大，照样被发现；
+   * - 只有「删掉非最大的那张且不新增」才不变，而此时集合缩小、无需重扫。
+   *
+   * 仍然是一条 SQL 聚合，**不解密任何图片**，成本与 count 同量级。
+   */
+  async imageConversationWatermarkAsync(
+    md5OrUsername: string,
+    sinceMs?: number
+  ): Promise<{ count: number; maxLocalId: number } | null> {
+    if (!this.wcdbGetMessageTableStats || !this.wcdbExecQuery) return null
+    // 与计数同因：必须先把会话 md5 解析成原生接口要的 username，否则永远匹配不到消息表。
+    const username = this.resolveMessageUsername(md5OrUsername)
+    if (!username) return null
+
+    let tables: Wcdb4MessageStore[]
+    try {
+      tables = await this.listMessageStoresAsync(username)
+    } catch {
+      return null
+    }
+
+    let count = 0
+    let maxLocalId = 0
+    for (const table of tables) {
+      // 同样探测真实列名：硬编码列名会让水位查询静默失败，进而退化成"永远重扫"或"永远跳过"。
+      const column = this.resolveMessageTypeColumn(table)
+      if (!column) return null
+      try {
+        const rows = await this.callJsonAsync<Record<string, unknown>[]>(
+          this.wcdbExecQuery as unknown as KoffiAsyncFunction,
+          'message',
+          table.dbPath,
+          `SELECT COUNT(*) AS "image_count", MAX("local_id") AS "image_max_local_id" FROM ${this.quoteSqlIdentifier(table.tableName)} WHERE ${this.imageMessageWhere(column, sinceMs)}`
+        )
+        const row = rows[0] || {}
+        const tableCount = Number(this.pickValue(row, ['image_count', 'count', 'COUNT(*)']))
+        const tableMax = Number(
+          this.pickValue(row, ['image_max_local_id', 'max_local_id', 'MAX("local_id")'])
+        )
+        if (Number.isFinite(tableCount)) count += tableCount
+        if (Number.isFinite(tableMax) && tableMax > maxLocalId) maxLocalId = tableMax
+      } catch (error) {
+        console.warn(
+          `[WCDB4] image watermark failed username=${username} db=${table.dbPath} table=${table.tableName}:`,
+          error
+        )
+        return null
+      }
+    }
+    return { count, maxLocalId }
+  }
+
   private readSessionRows(): Record<string, unknown>[] {
     if (!this.wcdbGetSessions) return []
     const rows = this.callJson<Record<string, unknown>[]>((handle, outJson) =>
diff --git a/src/preload/index.d.ts b/src/preload/index.d.ts
index 7e8bd3a..02cc581 100644
--- a/src/preload/index.d.ts
+++ b/src/preload/index.d.ts
@@ -58,6 +58,12 @@ import type {
   ImageInsight
 } from '../shared/image-insight'
 import type { SystemOcrCapability, SystemOcrRequest, SystemOcrResult } from '../shared/system-ocr'
+import type {
+  ImageTextIndexCountResult,
+  ImageTextIndexRepairResult,
+  ImageTextIndexStartOptions,
+  ImageTextIndexStatus
+} from '../shared/image-text-index'
 import type { AgentHubActionResult, AgentHubLogEntry, AgentHubStatus } from '../shared/agent-hub'
 import type {
   PersonalWechatGeneratedTtsVoiceRequest,
@@ -95,7 +101,7 @@ import type {
   AppUpdateOpenDownloadPageResult,
   AppUpdateState
 } from '../shared/app-update'
-import type { CacheSummary } from '../shared/cache'
+import type { CacheClearScope, CacheSummary } from '../shared/cache'
 import type { ExportRequest, ExportJobProgress, ExportResult } from '../shared/export'
 import type {
   VoiceBatchPreflight,
@@ -211,7 +217,7 @@ declare global {
       openAppUpdateDownloadPage: () => Promise<AppUpdateOpenDownloadPageResult>
       onAppUpdateState: (callback: (state: AppUpdateState) => void) => () => void
       getCacheSummary: () => Promise<CacheSummary>
-      clearCache: (scope: 'bootstrap' | 'electron' | 'knowledge' | 'all') => Promise<CacheSummary>
+      clearCache: (scope: CacheClearScope) => Promise<CacheSummary>
       openKnowledgeDirectory: () => Promise<{ success: boolean; error?: string }>
       initDb: (key: string, accountRoot: string) => Promise<boolean | DatabaseInitResult>
       discoverAccounts: (inputPath: string) => Promise<AccountDiscoveryResult>
@@ -664,6 +670,16 @@ declare global {
       // 本地图片文字识别（System OCR，本地 Runtime，非 AI Provider）
       getSystemOcrCapability: () => Promise<SystemOcrCapability>
       recognizeLocalImageText: (request: SystemOcrRequest) => Promise<SystemOcrResult>
+      getImageTextIndexStatus: () => Promise<ImageTextIndexStatus>
+      countImageMessages: (sinceMs?: number) => Promise<ImageTextIndexCountResult>
+      startImageTextIndex: (options?: ImageTextIndexStartOptions) => Promise<{ started: boolean; state: string }>
+      pauseImageTextIndex: () => Promise<{ paused: boolean; state: string }>
+      resumeImageTextIndex: (options?: ImageTextIndexStartOptions) => Promise<{ started: boolean; state: string }>
+      cancelImageTextIndex: () => Promise<{ cancellable: boolean; cancelled: boolean }>
+      clearImageTextIndex: () => Promise<{ removed: boolean; removedBytes: number }>
+      resetImageTextIndexFailures: () => Promise<{ reset: number }>
+      repairImageTextIndex: () => Promise<ImageTextIndexRepairResult>
+      onImageTextIndexStatus: (callback: (status: ImageTextIndexStatus) => void) => () => void
       getPersonalWechatSenderStatus: () => Promise<PersonalWechatSenderStatus>
       getPersonalWechatSendCapability: () => Promise<PersonalWechatSendCapability>
       getPersonalWechatKeepOneBotProcess: () => Promise<boolean>
diff --git a/src/preload/index.ts b/src/preload/index.ts
index 1f17ae3..77a0afa 100644
--- a/src/preload/index.ts
+++ b/src/preload/index.ts
@@ -31,6 +31,12 @@ import type {
   ImageInsight
 } from '../shared/image-insight'
 import type { SystemOcrCapability, SystemOcrRequest, SystemOcrResult } from '../shared/system-ocr'
+import type {
+  ImageTextIndexCountResult,
+  ImageTextIndexRepairResult,
+  ImageTextIndexStartOptions,
+  ImageTextIndexStatus
+} from '../shared/image-text-index'
 import type { AgentHubLogEntry, AgentHubStatus } from '../shared/agent-hub'
 import type {
   PersonalWechatGeneratedTtsVoiceRequest,
@@ -63,7 +69,7 @@ import type { AppLogEntry } from '../shared/app-log'
 import type { AppUpdateState } from '../shared/app-update'
 import type { GroupExitMonitorState } from '../shared/group-exit-monitor'
 import type { ActionLogEntry } from '../shared/action-log'
-import type { CacheSummary } from '../shared/cache'
+import type { CacheClearScope, CacheSummary } from '../shared/cache'
 import type { ExportRequest, ExportJobProgress } from '../shared/export'
 import type { ImageDecoderSelectionResult, ImageDecoderStatus } from '../shared/image-decryption'
 import type { AccountDiscoveryResult } from '../shared/database-key'
@@ -123,7 +129,7 @@ const api = {
     return () => ipcRenderer.removeListener('app-update:state', listener)
   },
   getCacheSummary: (): Promise<CacheSummary> => ipcRenderer.invoke('cache:getSummary'),
-  clearCache: (scope: 'bootstrap' | 'electron' | 'knowledge' | 'all'): Promise<CacheSummary> =>
+  clearCache: (scope: CacheClearScope): Promise<CacheSummary> =>
     ipcRenderer.invoke('cache:clear', scope),
   openKnowledgeDirectory: (): Promise<{ success: boolean; error?: string }> =>
     ipcRenderer.invoke('cache:openKnowledgeDirectory'),
@@ -468,6 +474,39 @@ const api = {
     ipcRenderer.invoke('system-ocr:getCapability'),
   recognizeLocalImageText: (request: SystemOcrRequest): Promise<SystemOcrResult> =>
     ipcRenderer.invoke('system-ocr:recognize', request),
+
+  // 图片文字索引（微信图片 → 本地解密 → System OCR → 派生文本 → Knowledge）
+  getImageTextIndexStatus: (): Promise<ImageTextIndexStatus> =>
+    ipcRenderer.invoke('image-text-index:getStatus'),
+  /** 点击索引前的快速统计（SQL COUNT，不解密图片）。 */
+  countImageMessages: (sinceMs?: number): Promise<ImageTextIndexCountResult> =>
+    ipcRenderer.invoke('image-text-index:count', sinceMs),
+  startImageTextIndex: (options?: ImageTextIndexStartOptions): Promise<{ started: boolean; state: string }> =>
+    ipcRenderer.invoke('image-text-index:start', options),
+  pauseImageTextIndex: (): Promise<{ paused: boolean; state: string }> =>
+    ipcRenderer.invoke('image-text-index:pause'),
+  resumeImageTextIndex: (options?: ImageTextIndexStartOptions): Promise<{ started: boolean; state: string }> =>
+    ipcRenderer.invoke('image-text-index:resume', options),
+  cancelImageTextIndex: (): Promise<{ cancellable: boolean; cancelled: boolean }> =>
+    ipcRenderer.invoke('image-text-index:cancel'),
+  clearImageTextIndex: (): Promise<{ removed: boolean; removedBytes: number }> =>
+    ipcRenderer.invoke('image-text-index:clear'),
+  /** 只重置失败记录（成功记录与其它数据不动），供"修好代码后重跑"。 */
+  resetImageTextIndexFailures: (): Promise<{ reset: number }> =>
+    ipcRenderer.invoke('image-text-index:resetFailures'),
+  /**
+   * 派生索引修复：只重建 Knowledge 里的图片派生条目与 FTS。
+   *
+   * 已有的 OCR 结果（L1）一条都不动 —— 修复索引问题永远不该让几万张图片重算。
+   */
+  repairImageTextIndex: (): Promise<ImageTextIndexRepairResult> =>
+    ipcRenderer.invoke('image-text-index:repair'),
+  onImageTextIndexStatus: (callback: (status: ImageTextIndexStatus) => void) => {
+    const listener = (_event: Electron.IpcRendererEvent, status: ImageTextIndexStatus): void =>
+      callback(status)
+    ipcRenderer.on('image-text-index:status', listener)
+    return () => ipcRenderer.removeListener('image-text-index:status', listener)
+  },
   getPersonalWechatSenderStatus: (): Promise<PersonalWechatSenderStatus> =>
     ipcRenderer.invoke('wechat-personal:getStatus'),
   getPersonalWechatSendCapability: (): Promise<PersonalWechatSendCapability> =>
diff --git a/src/renderer/src/components/search/AISearchEvidencePanel.tsx b/src/renderer/src/components/search/AISearchEvidencePanel.tsx
index 53ca656..b3177c6 100644
--- a/src/renderer/src/components/search/AISearchEvidencePanel.tsx
+++ b/src/renderer/src/components/search/AISearchEvidencePanel.tsx
@@ -77,9 +77,27 @@ export function AISearchEvidencePanel({
                 {item.sourceKind === 'voice' && (
                   <span className="block text-[11px] font-semibold text-primary">语音转写</span>
                 )}
+                {item.derivedSource === 'image_ocr' && (
+                  <span
+                    className="mt-0.5 inline-block rounded-sm bg-accent px-1.5 py-0.5 text-[10px] font-semibold text-primary"
+                    data-testid="evidence-image-ocr-badge"
+                  >
+                    图片文字
+                  </span>
+                )}
                 <span className="mt-[7px] block overflow-hidden text-[11px] leading-[17px] text-muted-foreground [display:-webkit-box] [-webkit-box-orient:vertical] [-webkit-line-clamp:3]">
                   {messageText(item.message)}
                 </span>
+                {/* 命中解释：明确告诉用户"命中的是图里的这段文字"，
+                    避免被读成群友真的发过一条这样的文字消息。 */}
+                {item.derivedSource === 'image_ocr' && item.imageOcrText && (
+                  <span
+                    className="mt-1 block overflow-hidden text-[11px] leading-[17px] text-foreground [display:-webkit-box] [-webkit-box-orient:vertical] [-webkit-line-clamp:3]"
+                    data-testid="evidence-image-ocr-snippet"
+                  >
+                    “{item.imageOcrText}”
+                  </span>
+                )}
                 <Button
                   variant="link"
                   size="sm"
diff --git a/src/renderer/src/components/search/AISearchWorkspace.tsx b/src/renderer/src/components/search/AISearchWorkspace.tsx
index 5da93fe..9bdc0a4 100644
--- a/src/renderer/src/components/search/AISearchWorkspace.tsx
+++ b/src/renderer/src/components/search/AISearchWorkspace.tsx
@@ -43,6 +43,7 @@ import { ensureAiSearchDataConsent } from './services/aiSearchProviderConsent'
 import { ExternalProviderConsentDialog } from './ExternalProviderConsentDialog'
 import { AISearchComposer } from './AISearchComposer'
 import { AISearchEvidencePanel } from './AISearchEvidencePanel'
+import { ImageTextIndexCard } from './ImageTextIndexCard'
 import {
   forgetAskWechatConversation,
   requestAskWechatQuery,
@@ -1394,6 +1395,9 @@ export function AISearchWorkspace({
               <p>索引独立保存，不会删除或修改微信原始数据库。</p>
             </details>
           </section>
+          {/* 图片文字索引：与 Knowledge 卡片平级、但**独立的一维能力**。
+              文字消息索引完整不代表图片里的文字搜得到，所以两个入口必须并列可见。 */}
+          <ImageTextIndexCard dbReady={dbReady} onNotice={onNotice} />
         </aside>
         <main className="ai-search-main">
           <div className="ai-search-main-scroll">
diff --git a/src/renderer/src/components/search/ImageTextIndexCard.tsx b/src/renderer/src/components/search/ImageTextIndexCard.tsx
new file mode 100644
index 0000000..97e5c0e
--- /dev/null
+++ b/src/renderer/src/components/search/ImageTextIndexCard.tsx
@@ -0,0 +1,427 @@
+import { useEffect, useMemo, useState, type ReactElement } from 'react'
+import {
+  AlertDialog,
+  AlertDialogAction,
+  AlertDialogCancel,
+  AlertDialogContent,
+  AlertDialogFooter,
+  AlertDialogHeader,
+  AlertDialogTitle,
+  Button,
+  Select,
+  SelectContent,
+  SelectItem,
+  SelectTrigger,
+  SelectValue
+} from '../ui'
+import {
+  describeImageTextCoverage,
+  imageTextCoverageState,
+  imageTextProcessedPercent
+} from '../../../../shared/image-text-index'
+import { useImageTextIndexStatus } from './hooks/useImageTextIndexStatus'
+
+type ImageTextIndexCardProps = {
+  /** 微信数据是否就绪。 */
+  dbReady: boolean
+  onNotice: (message: string) => void
+}
+
+/**
+ * 「图片文字索引」卡片。
+ *
+ * 与 Knowledge 卡片**平级并列**（同一组索引入口），但刻意是**独立的一维能力**：
+ * 文字消息索引完整不代表图片里的文字搜得到。
+ *
+ * 文案遵从严禁混淆的语义（§9）：这里做的是「识别图片中文字」，不是
+ * 「本地识图模型 / 本地 Vision / AI OCR」，也不能暗示能理解场景或表情包。
+ */
+export function ImageTextIndexCard({ dbReady, onNotice }: ImageTextIndexCardProps): ReactElement {
+  const {
+    status,
+    count,
+    counting,
+    pending,
+    running,
+    paused,
+    established,
+    refreshCount,
+    start,
+    pause,
+    resume,
+    cancel,
+    resetFailures,
+    repair
+  } = useImageTextIndexStatus({ dbReady, onNotice })
+  const [confirming, setConfirming] = useState(false)
+  const [confirmCount, setConfirmCount] = useState<number | null>(null)
+  /**
+   * 处理时间范围（天）。
+   *
+   * 存在的意义是**可验证性**：几万张图片的全量回填没法拿来排查问题，
+   * 先跑"最近 1 天"这种小窗口才能证明链路真的通了。`0` = 全部历史。
+   */
+  const [rangeDays, setRangeDays] = useState('0')
+  const sinceMs = useMemo(() => {
+    const days = Number(rangeDays)
+    return Number.isFinite(days) && days > 0 ? Date.now() - days * 24 * 60 * 60 * 1000 : undefined
+  }, [rangeDays])
+
+  // 进页面 / 切换范围时统计一次（数字必须与当前窗口一致，否则确认弹窗会说谎）。
+  useEffect(() => {
+    if (!dbReady) return
+    void refreshCount(sinceMs)
+  }, [dbReady, sinceMs, refreshCount])
+
+  const coverage = status?.coverage ?? null
+  const progress = status?.progress ?? null
+  const coverageState = coverage ? imageTextCoverageState(coverage) : 'not_built'
+  /**
+   * 处理进度百分比。
+   *
+   * 刻意不在这里做 `Math.round(x * 100)` —— `45479 / 45707` 会被四舍五入成 `100`，
+   * 于是出现了"已建立 · 仅完成 100%"这种自相矛盾的显示。未完成时封顶 99.9%。
+   */
+  const percent = coverage
+    ? imageTextProcessedPercent(coverage.processed, coverage.totalImageMessages)
+    : 0
+  const systemicFailure = coverage?.systemicFailure === true
+  const visualState =
+    progress?.state === 'error' || coverageState === 'failed'
+      ? 'error'
+      : running
+        ? 'syncing'
+        : paused
+          ? 'cancelled'
+          : !established
+            ? 'unavailable'
+            : coverageState === 'complete'
+              ? 'ready'
+              : 'building'
+
+  const detectedImages = count?.totalImageMessages ?? coverage?.totalImageMessages ?? null
+  const countFailed = count !== null && count.failedConversations > 0
+  /**
+   * 一个会话都没数成。
+   *
+   * 这时**绝不能显示 0** —— 那会让用户以为账号里没有图片，从而放弃建立索引。
+   * 数不出来和确实没有是两件事。
+   */
+  const nothingCounted =
+    count !== null && count.scannedConversations === 0 && count.failedConversations > 0
+
+  const stateLabel = (() => {
+    if (progress?.state === 'error') return '建立失败'
+    if (running) return `建立中 · ${percent}%`
+    if (paused) return `已暂停 · ${percent}%`
+    if (!established) return '未建立'
+    // 「已建立」不能等于「全失败」：处理过但一条都没成功时必须叫异常。
+    if (coverageState === 'failed') return '图片文字索引异常'
+    if (coverageState === 'complete') return '已完成'
+    return `部分完成 · ${percent}%`
+  })()
+
+  /**
+   * 点「建立图片文字索引」：**先重新统计、再弹确认**。
+   *
+   * 确认弹窗里的数字必须新鲜——用户可能刚在微信里收了一批图片。
+   * 统计是纯 SQL COUNT，不解密任何图片，所以这一步够快。
+   */
+  const requestStart = async (): Promise<void> => {
+    const fresh = await refreshCount(sinceMs)
+    setConfirmCount(fresh?.totalImageMessages ?? detectedImages)
+    setConfirming(true)
+  }
+
+  const confirmStart = async (): Promise<void> => {
+    setConfirming(false)
+    await start({ ...(sinceMs ? { sinceMs } : {}) })
+  }
+
+  return (
+    <>
+      <section
+        className={`ai-search-knowledge-card ${visualState}`}
+        aria-label="图片文字索引状态"
+      >
+        <div className="ai-search-knowledge-heading">
+          <div className="ai-search-knowledge-heading-text">
+            <span className="ai-search-knowledge-kicker">IMAGE TEXT INDEX</span>
+            <strong className="ai-search-knowledge-state" data-testid="image-text-index-state">
+              {stateLabel}
+            </strong>
+          </div>
+          <span className="ai-search-knowledge-dot" aria-hidden />
+        </div>
+
+        <p className="ai-search-knowledge-description">
+          让「问问微信」也能搜索微信图片中的文字（截图、报价图、公告截图等）。
+          识别在本机进行，原始图片无需发送给 AI Provider。
+        </p>
+
+        {/* 未建立：先告诉用户这个账号大概有多少图片，再让他决定要不要跑。 */}
+        {!established && !running && (
+          <>
+            <div className="ai-search-knowledge-rows">
+              <div className="ai-search-knowledge-row">
+                <span className="ai-search-knowledge-label">检测到的图片消息</span>
+                <strong className="ai-search-knowledge-value" data-testid="image-text-index-count">
+                  {counting
+                    ? '统计中…'
+                    : nothingCounted
+                      ? '无法统计'
+                      : detectedImages === null
+                        ? '—'
+                        : detectedImages.toLocaleString()}
+                </strong>
+              </div>
+            </div>
+            <div className="ai-search-knowledge-row">
+              <span className="ai-search-knowledge-label">处理范围</span>
+              <Select value={rangeDays} onValueChange={setRangeDays}>
+                <SelectTrigger data-testid="image-text-index-range" className="h-6 w-[86px] text-[10px]">
+                  <SelectValue />
+                </SelectTrigger>
+                <SelectContent>
+                  <SelectItem value="0">全量</SelectItem>
+                  <SelectItem value="1">近 1 天</SelectItem>
+                  <SelectItem value="7">近 7 天</SelectItem>
+                  <SelectItem value="30">近 30 天</SelectItem>
+                </SelectContent>
+              </Select>
+            </div>
+            {countFailed && (
+              <p className="ai-search-knowledge-error" data-testid="image-text-index-count-error">
+                {nothingCounted
+                  ? `无法统计本账号的图片消息（${count?.error || '读取消息表失败'}）。这不代表账号里没有图片，可以点「重新统计」再试一次。`
+                  : `有 ${count?.failedConversations.toLocaleString()} 个会话未能统计，上面的数字可能偏小。`}
+              </p>
+            )}
+          </>
+        )}
+
+        {/* 进度：只给真实数字，绝不显示 native handle / hash / HRESULT。 */}
+        {(running || paused) && progress && (
+          <div className="ai-search-knowledge-pass">
+            <div className="ai-search-knowledge-rows">
+              <div className="ai-search-knowledge-row">
+                <span className="ai-search-knowledge-label">已处理</span>
+                <strong
+                  className="ai-search-knowledge-value"
+                  data-testid="image-text-index-progress"
+                >
+                  {`${progress.processed.toLocaleString()} / ${progress.totalImageMessages.toLocaleString()}`}
+                </strong>
+              </div>
+            </div>
+            <div className="ai-search-sync-progress-track">
+              <span
+                style={{
+                  width: `${Math.min(100, Math.max(0, progress.percent))}%`,
+                  ...(progress.totalImageMessages > 0
+                    ? {}
+                    : { animation: 'ai-search-indeterminate 1.4s ease-in-out infinite' })
+                }}
+              />
+            </div>
+            <p className="ai-search-knowledge-pass-line">
+              {`${progress.percent}% · 识别出文字 ${progress.indexed.toLocaleString()} · 没有文字 ${progress.empty.toLocaleString()} · 图片已清理 ${progress.missing.toLocaleString()} · 失败 ${progress.failed.toLocaleString()}`}
+            </p>
+          </div>
+        )}
+
+        {/* 已建立：给一份可核对的明细。 */}
+        {established && !running && !paused && coverage && (
+          <div className="ai-search-knowledge-rows">
+            <div className="ai-search-knowledge-row">
+              <span className="ai-search-knowledge-label">已识别出文字</span>
+              <strong className="ai-search-knowledge-value">
+                {coverage.indexed.toLocaleString()}
+              </strong>
+            </div>
+            <div className="ai-search-knowledge-row">
+              <span className="ai-search-knowledge-label">没有文字</span>
+              <strong className="ai-search-knowledge-value">{coverage.empty.toLocaleString()}</strong>
+            </div>
+            <div className="ai-search-knowledge-row">
+              <span className="ai-search-knowledge-label">图片已清理</span>
+              <strong className="ai-search-knowledge-value">
+                {coverage.missing.toLocaleString()}
+              </strong>
+            </div>
+            {coverage.failed > 0 && (
+              <div className="ai-search-knowledge-row">
+                <span className="ai-search-knowledge-label">识别失败</span>
+                <strong className="ai-search-knowledge-value">
+                  {coverage.failed.toLocaleString()}
+                </strong>
+              </div>
+            )}
+            <p className="ai-search-knowledge-pass-line">{describeImageTextCoverage(coverage)}</p>
+          </div>
+        )}
+
+        {progress?.state === 'error' && (
+          <p className="ai-search-knowledge-error">
+            {progress.lastError || '图片文字索引建立失败，可以稍后重试。'}
+          </p>
+        )}
+        {/* 「处理过但一条都没成功」= 索引异常，绝不能显示成"已建立"。 */}
+        {systemicFailure && (
+          <p
+            className="ai-search-knowledge-error"
+            data-testid="image-text-index-systemic-failure"
+          >
+            {`${(coverage?.failed ?? 0).toLocaleString()} 条处理失败，成功识别 0 条 —— 当前无法搜索图片中的文字。`}
+          </p>
+        )}
+        {paused && (
+          <p className="ai-search-knowledge-error">
+            已暂停。已经识别出的结果都保留了，点「继续」会从断点接着做，不会从第一张重新开始。
+          </p>
+        )}
+        {!dbReady && (
+          <p className="ai-search-knowledge-error">请先连接微信数据，然后再建立图片文字索引。</p>
+        )}
+
+        <div className="ai-search-knowledge-actions">
+          {!running && !paused && (
+            <Button
+              size="sm"
+              className="ai-search-knowledge-primary"
+              data-testid="image-text-index-start"
+              disabled={!dbReady || pending !== null || counting}
+              onClick={() => void requestStart()}
+            >
+              {established ? '更新图片文字索引' : '建立图片文字索引'}
+            </Button>
+          )}
+          {!running && !paused && countFailed && (
+            <Button
+              size="sm"
+              variant="outline"
+              className="ai-search-knowledge-cancel"
+              data-testid="image-text-index-recount"
+              disabled={pending !== null || counting}
+              onClick={() => void refreshCount()}
+            >
+              {counting ? '统计中…' : '重新统计'}
+            </Button>
+          )}
+          {/* 修好之后重跑：只重置失败记录，成功记录与其它数据一律不动。 */}
+          {!running && !paused && systemicFailure && (
+            <Button
+              size="sm"
+              variant="outline"
+              className="ai-search-knowledge-cancel"
+              data-testid="image-text-index-reset-failures"
+              disabled={pending !== null}
+              onClick={() => void resetFailures()}
+            >
+              {pending === 'reset' ? '处理中…' : '重试失败的图片'}
+            </Button>
+          )}
+          {/* 派生索引修复：只重建 Knowledge 里的图片搜索索引，**不重新识别任何图片**。
+              存在的意义就是"别为修一个索引问题重跑几万张图"。 */}
+          {!running && !paused && established && (
+            <Button
+              size="sm"
+              variant="outline"
+              className="ai-search-knowledge-cancel"
+              data-testid="image-text-index-repair"
+              disabled={pending !== null}
+              onClick={() => void repair()}
+            >
+              {pending === 'repair' ? '修复中…' : '修复图片搜索索引'}
+            </Button>
+          )}
+          {running && (
+            <>
+              <Button
+                size="sm"
+                variant="outline"
+                className="ai-search-knowledge-cancel"
+                data-testid="image-text-index-pause"
+                disabled={pending !== null}
+                onClick={() => void pause()}
+              >
+                {pending === 'pause' ? '暂停中…' : '暂停'}
+              </Button>
+              <Button
+                size="sm"
+                variant="outline"
+                className="ai-search-knowledge-cancel"
+                data-testid="image-text-index-cancel"
+                disabled={pending !== null}
+                onClick={() => void cancel()}
+              >
+                {pending === 'cancel' ? '取消中…' : '取消'}
+              </Button>
+            </>
+          )}
+          {paused && (
+            <>
+              <Button
+                size="sm"
+                className="ai-search-knowledge-primary"
+                data-testid="image-text-index-resume"
+                disabled={pending !== null}
+                onClick={() => void resume()}
+              >
+                {pending === 'resume' ? '继续中…' : '继续'}
+              </Button>
+              <Button
+                size="sm"
+                variant="outline"
+                className="ai-search-knowledge-cancel"
+                data-testid="image-text-index-cancel"
+                disabled={pending !== null}
+                onClick={() => void cancel()}
+              >
+                取消
+              </Button>
+            </>
+          )}
+        </div>
+      </section>
+
+      <AlertDialog open={confirming} onOpenChange={setConfirming}>
+        <AlertDialogContent>
+          <AlertDialogHeader>
+            <AlertDialogTitle>建立图片文字索引</AlertDialogTitle>
+          </AlertDialogHeader>
+          <div className="ai-search-knowledge-confirm">
+            <p>
+              当前账号检测到约{' '}
+              <strong>
+                {confirmCount === null ? '未知数量' : confirmCount.toLocaleString()} 条图片消息
+              </strong>
+              。
+            </p>
+            <p>
+              建立后，TraceMemo 会在本机读取这些图片中的文字，以后可以在「问问微信」里搜索截图、
+              报价图、公告截图等图片里的文字，并按结果回到对应的原始图片消息。
+            </p>
+            <p>识别过程：</p>
+            <ul>
+              <li>仅在本机进行识别，原始图片不会因为本地识别而自动上传</li>
+              <li>可能需要较长时间，可以暂停并稍后继续</li>
+              <li>图片已被微信清理或无法解密时会自动跳过</li>
+              <li>实际可识别的数量取决于本地图片文件是否仍然存在</li>
+            </ul>
+            <p>不会修改或删除微信原始图片与聊天记录。</p>
+          </div>
+          <AlertDialogFooter>
+            <AlertDialogCancel>取消</AlertDialogCancel>
+            <AlertDialogAction
+              data-testid="image-text-index-confirm"
+              onClick={() => void confirmStart()}
+            >
+              开始索引
+            </AlertDialogAction>
+          </AlertDialogFooter>
+        </AlertDialogContent>
+      </AlertDialog>
+    </>
+  )
+}
diff --git a/src/renderer/src/components/search/askWechatPresentation.ts b/src/renderer/src/components/search/askWechatPresentation.ts
index e1515a1..70080b3 100644
--- a/src/renderer/src/components/search/askWechatPresentation.ts
+++ b/src/renderer/src/components/search/askWechatPresentation.ts
@@ -52,6 +52,10 @@ export function mapAskWechatEvidence(items: AskWechatEvidenceItem[]): EvidenceIt
     return {
       evidenceId: `E${index + 1}`,
       sourceKind: item.messageType as EvidenceItem['sourceKind'],
+      // 「靠图片里的文字命中」是来源语义，必须原样带到 UI；
+      // 但 authoritative source 仍然是原始图片消息（messageRef 已指向它）。
+      ...(item.derivedSource ? { derivedSource: item.derivedSource } : {}),
+      ...(item.imageOcrText ? { imageOcrText: item.imageOcrText } : {}),
       contact: evidenceContact(item, anchor),
       messageRef: item.messageRef,
       message: {
diff --git a/src/renderer/src/components/search/hooks/useImageTextIndexStatus.ts b/src/renderer/src/components/search/hooks/useImageTextIndexStatus.ts
new file mode 100644
index 0000000..885d7aa
--- /dev/null
+++ b/src/renderer/src/components/search/hooks/useImageTextIndexStatus.ts
@@ -0,0 +1,235 @@
+import { useCallback, useEffect, useState } from 'react'
+import type {
+  ImageTextIndexCountResult,
+  ImageTextIndexStartOptions,
+  ImageTextIndexStatus
+} from '../../../../../shared/image-text-index'
+
+type UseImageTextIndexStatusOptions = {
+  /** 微信数据是否已就绪。未就绪时既不统计也不允许建立索引。 */
+  dbReady: boolean
+  onNotice: (message: string) => void
+}
+
+export type ImageTextIndexAction = 'start' | 'pause' | 'resume' | 'cancel' | 'reset' | 'repair'
+
+/**
+ * 「图片文字索引」的 renderer 侧状态。
+ *
+ * 三条不能省的语义：
+ * 1. **重启后进度是真的**：进度与覆盖度全部来自主进程的派生库快照，
+ *    renderer 不自己累加、也不缓存百分比。应用重启后重新拉一次即可恢复真实进度。
+ * 2. **数量统计是显式动作**：COUNT(*) 要走一遍会话列表，不在每次渲染时触发；
+ *    只在「未建立」时拉一次、以及点击建立前重新拉一次（确认弹窗里的数字必须新鲜）。
+ * 3. **暂停 / 继续 / 取消都是待确认操作**：主进程返回 started/paused/cancelled
+ *    才提示成功；例如 `started: false` 表示已经有任务在跑，此时说"已开始"是假话。
+ */
+export function useImageTextIndexStatus({
+  dbReady,
+  onNotice
+}: UseImageTextIndexStatusOptions): {
+  status: ImageTextIndexStatus | null
+  count: ImageTextIndexCountResult | null
+  counting: boolean
+  pending: ImageTextIndexAction | null
+  running: boolean
+  paused: boolean
+  established: boolean
+  refreshCount: (sinceMs?: number) => Promise<ImageTextIndexCountResult | null>
+  start: (options?: ImageTextIndexStartOptions) => Promise<void>
+  pause: () => Promise<void>
+  resume: () => Promise<void>
+  cancel: () => Promise<void>
+  resetFailures: () => Promise<void>
+  repair: () => Promise<void>
+} {
+  const [status, setStatus] = useState<ImageTextIndexStatus | null>(null)
+  const [count, setCount] = useState<ImageTextIndexCountResult | null>(null)
+  const [counting, setCounting] = useState(false)
+  const [pending, setPending] = useState<ImageTextIndexAction | null>(null)
+
+  useEffect(() => {
+    // 这是一个**次要侧栏能力**：桥接缺失（旧 preload / 测试里手写的 window.api）
+    // 或推送异常，都不允许把整个「问问微信」拖垮。缺少桥接时按「未建立」降级即可。
+    const bridge = window.api as unknown as {
+      getImageTextIndexStatus?: () => Promise<ImageTextIndexStatus>
+      onImageTextIndexStatus?: (
+        callback: (status: ImageTextIndexStatus) => void
+      ) => (() => void) | undefined
+    }
+    const loadStatus = bridge.getImageTextIndexStatus
+    const subscribe = bridge.onImageTextIndexStatus
+    if (typeof loadStatus !== 'function' || typeof subscribe !== 'function') return
+
+    let active = true
+    void loadStatus
+      .call(bridge)
+      .then((snapshot) => {
+        if (active) setStatus(snapshot)
+      })
+      .catch(() => undefined)
+    const unsubscribe = subscribe((snapshot) => {
+      if (active) setStatus(snapshot)
+    })
+    return () => {
+      active = false
+      if (typeof unsubscribe === 'function') unsubscribe()
+    }
+  }, [])
+
+  const refreshCount = useCallback(
+    async (sinceMs?: number): Promise<ImageTextIndexCountResult | null> => {
+    if (!dbReady) return null
+    setCounting(true)
+    try {
+      const result = await window.api.countImageMessages(sinceMs)
+      setCount(result)
+      return result
+    } catch (error) {
+      onNotice(error instanceof Error ? error.message : '统计图片消息数量失败')
+      return null
+    } finally {
+      setCounting(false)
+    }
+    },
+    [dbReady, onNotice]
+  )
+
+  const established = status?.coverage.established ?? false
+  void established
+
+  const start = useCallback(
+    async (options?: ImageTextIndexStartOptions): Promise<void> => {
+      if (!dbReady) {
+        onNotice('请先连接微信数据后再建立图片文字索引')
+        return
+      }
+      setPending('start')
+      try {
+        const result = await window.api.startImageTextIndex(options)
+        if (!result.started) {
+          onNotice('图片文字索引已经在进行中')
+          return
+        }
+        onNotice('已开始建立图片文字索引，可以继续使用软件')
+      } catch (error) {
+        onNotice(error instanceof Error ? error.message : '启动图片文字索引失败')
+      } finally {
+        setPending(null)
+      }
+    },
+    [dbReady, onNotice]
+  )
+
+  const pause = useCallback(async (): Promise<void> => {
+    setPending('pause')
+    try {
+      const result = await window.api.pauseImageTextIndex()
+      onNotice(result.paused ? '已暂停，已完成的识别结果会保留' : '当前没有正在进行的索引')
+    } catch (error) {
+      onNotice(error instanceof Error ? error.message : '暂停失败')
+    } finally {
+      setPending(null)
+    }
+  }, [onNotice])
+
+  const resume = useCallback(
+    async (options?: ImageTextIndexStartOptions): Promise<void> => {
+      setPending('resume')
+      try {
+        const result = await window.api.resumeImageTextIndex(options)
+        onNotice(result.started ? '已继续建立图片文字索引' : '索引已经在进行中')
+      } catch (error) {
+        onNotice(error instanceof Error ? error.message : '继续失败')
+      } finally {
+        setPending(null)
+      }
+    },
+    [onNotice]
+  )
+
+  const cancel = useCallback(async (): Promise<void> => {
+    setPending('cancel')
+    try {
+      const result = await window.api.cancelImageTextIndex()
+      if (!result.cancellable) {
+        onNotice('当前没有正在进行的索引')
+        return
+      }
+      if (!result.cancelled) {
+        onNotice('索引刚刚已经结束，无需取消')
+        return
+      }
+      onNotice('已取消，已识别的结果会保留，下次可从中断处继续')
+    } catch (error) {
+      onNotice(error instanceof Error ? error.message : '取消失败')
+    } finally {
+      setPending(null)
+    }
+  }, [onNotice])
+
+  /**
+   * 重置失败记录（代码修好后重跑）。
+   *
+   * 只说"已重置 N 条"是不够的 —— 必须同时讲清楚**成功记录没有被删**，
+   * 否则用户会以为刚才把已经跑好的结果也清掉了。
+   */
+  const resetFailures = useCallback(async (): Promise<void> => {
+    setPending('reset')
+    try {
+      const result = await window.api.resetImageTextIndexFailures()
+      onNotice(
+        result.reset > 0
+          ? `已把 ${result.reset.toLocaleString()} 条失败记录重置为待处理；已成功识别的记录保持不变。可以点「更新图片文字索引」重新处理这些图片`
+          : '没有需要重置的失败记录'
+      )
+    } catch (error) {
+      onNotice(error instanceof Error ? error.message : '重置失败记录失败')
+    } finally {
+      setPending(null)
+    }
+  }, [onNotice])
+
+  /**
+   * 派生索引修复：只重建 Knowledge 里的图片派生条目（L3），**不重新 OCR**（L1 不动）。
+   *
+   * 措辞必须讲清楚"没有重新识别"：否则用户会以为又要等一小时，
+   * 从而不敢点这个按钮 —— 而这个按钮存在的全部意义就是"别重跑几万张图"。
+   */
+  const repair = useCallback(async (): Promise<void> => {
+    setPending('repair')
+    try {
+      const result = await window.api.repairImageTextIndex()
+      if (result.skipped) {
+        onNotice('索引任务正在进行中，请等它结束后再修复搜索索引')
+        return
+      }
+      onNotice(
+        result.conversations > 0
+          ? `已重建 ${result.conversations} 个会话的图片搜索索引；没有重新识别任何图片（已识别结果全部复用）`
+          : '没有需要重建的图片搜索索引'
+      )
+    } catch (error) {
+      onNotice(error instanceof Error ? error.message : '修复图片搜索索引失败')
+    } finally {
+      setPending(null)
+    }
+  }, [onNotice])
+
+  return {
+    status,
+    count,
+    counting,
+    pending,
+    running: status?.progress.state === 'running',
+    paused: status?.progress.state === 'paused',
+    established,
+    refreshCount,
+    start,
+    pause,
+    resume,
+    cancel,
+    resetFailures,
+    repair
+  }
+}
diff --git a/src/renderer/src/components/search/searchMappers.ts b/src/renderer/src/components/search/searchMappers.ts
index f6cc9b0..674325f 100644
--- a/src/renderer/src/components/search/searchMappers.ts
+++ b/src/renderer/src/components/search/searchMappers.ts
@@ -24,6 +24,10 @@ export const mapPipelineEvidenceItem = (
   return {
     evidenceId: item.id,
     sourceKind: item.sourceKind,
+    // 「靠图片里的文字命中」的来源语义与 OCR 片段同样要带到 UI，
+    // 否则 Legacy 检索路径下用户看不到「图片文字」标记（两条路径表现会不一致）。
+    ...(item.derivedSource ? { derivedSource: item.derivedSource } : {}),
+    ...(item.imageOcrText ? { imageOcrText: item.imageOcrText } : {}),
     contact,
     // 这条路径本来就同时知道真实会话 id 与消息 id，顺手补上稳定引用，
     // 让 Legacy / ai-search 证据也能被精确定位（而不是只有 Query Agent 路径能跳准）。
diff --git a/src/renderer/src/components/search/searchTypes.ts b/src/renderer/src/components/search/searchTypes.ts
index 5a6f08b..85e9247 100644
--- a/src/renderer/src/components/search/searchTypes.ts
+++ b/src/renderer/src/components/search/searchTypes.ts
@@ -34,6 +34,15 @@ export interface EvidenceItem {
   /** Program-owned Final Evidence ID. Cached legacy records may omit it. */
   evidenceId?: string
   sourceKind?: KnowledgeMessageKind
+  /**
+   * 命中所依赖的派生来源。
+   *
+   * `image_ocr` = 这条结果靠**图片里的文字**命中，而不是群友真的发了一条文字消息。
+   * 有值时 Evidence 卡片显示轻量来源标记（「图片文字」）。
+   */
+  derivedSource?: 'image_ocr'
+  /** 「从图片里读出来的文字」片段，只作命中解释。 */
+  imageOcrText?: string
   contact: Contact
   message: Message
   /**
diff --git a/src/renderer/src/features/settings/pages/CacheCleanupPage.tsx b/src/renderer/src/features/settings/pages/CacheCleanupPage.tsx
index 72c471c..3bb84d0 100644
--- a/src/renderer/src/features/settings/pages/CacheCleanupPage.tsx
+++ b/src/renderer/src/features/settings/pages/CacheCleanupPage.tsx
@@ -1,6 +1,16 @@
 import { useCallback, useEffect, useState } from 'react'
-import type { CacheSummary } from '../../../../../shared/cache'
-import { Button } from '../../../components/ui'
+import type { CacheSummary, CacheClearScope } from '../../../../../shared/cache'
+import {
+  AlertDialog,
+  AlertDialogAction,
+  AlertDialogCancel,
+  AlertDialogContent,
+  AlertDialogDescription,
+  AlertDialogFooter,
+  AlertDialogHeader,
+  AlertDialogTitle,
+  Button
+} from '../../../components/ui'
 
 const SEARCH_CACHE_KEYS = [
   'wxe_ai_search_cache_v8',
@@ -25,9 +35,9 @@ export function CacheCleanupPage({
   onNotice: (message: string) => void
 }): React.ReactElement {
   const [summary, setSummary] = useState<CacheSummary | null>(null)
-  const [busyScope, setBusyScope] = useState<
-    'bootstrap' | 'electron' | 'knowledge' | 'knowledge-directory' | 'all' | 'local' | null
-  >(null)
+  const [busyScope, setBusyScope] = useState<CacheClearScope | 'knowledge-directory' | 'local' | null>(null)
+  /** 需要二次确认的清理范围（目前只有图片文字索引）。 */
+  const [confirmingScope, setConfirmingScope] = useState<CacheClearScope | null>(null)
 
   const refresh = useCallback(async (): Promise<void> => {
     setSummary(await window.api.getCacheSummary())
@@ -44,7 +54,7 @@ export function CacheCleanupPage({
     onNotice('已清理检索和导出本地缓存')
   }
 
-  const clear = async (scope: 'bootstrap' | 'electron' | 'knowledge' | 'all'): Promise<void> => {
+  const clear = async (scope: CacheClearScope): Promise<void> => {
     setBusyScope(scope)
     try {
       setSummary(await window.api.clearCache(scope))
@@ -54,9 +64,11 @@ export function CacheCleanupPage({
       onNotice(
         scope === 'knowledge'
           ? '已清理所有账号的本地知识库索引，需要时可在问问微信中重新建立'
-          : scope === 'all'
-            ? '已清理全部可恢复缓存和检索记录'
-            : '缓存已清理'
+          : scope === 'image-text-index'
+            ? '已清理图片文字索引，微信原始图片与聊天记录未受影响；需要时可在问问微信中重新建立'
+            : scope === 'all'
+              ? '已清理全部可恢复缓存和检索记录'
+              : '缓存已清理'
       )
     } catch (error) {
       onNotice(error instanceof Error ? error.message : '清理缓存失败')
@@ -65,6 +77,33 @@ export function CacheCleanupPage({
     }
   }
 
+  /**
+   * 清理图片文字索引。两步各司其职，不能省成一步：
+   *
+   * 1. `clearImageTextIndex()` —— 主进程先停任务、折叠 WAL、关连接、删三件套，
+   *    并**回验文件是否真的删掉**（Windows 上文件被占用时 rmSync 会静默失败）。
+   * 2. `clearCache('image-text-index')` —— 再扫掉整个派生目录（含其它账号的派生库），
+   *    并返回刷新后的占用摘要。
+   *
+   * 只要第 1 步回验失败，就必须如实报告，不能说"已清理"。
+   */
+  const clearImageTextIndex = async (): Promise<void> => {
+    setBusyScope('image-text-index')
+    try {
+      const result = await window.api.clearImageTextIndex()
+      setSummary(await window.api.clearCache('image-text-index'))
+      onNotice(
+        result.removed
+          ? '已清理图片文字索引；微信原始图片、聊天记录和普通文字知识库都未受影响。需要时可在「问问微信」里重新建立'
+          : '图片文字索引的数据文件仍被占用，没能完全删除。请重启 TraceMemo 后再试一次'
+      )
+    } catch (error) {
+      onNotice(error instanceof Error ? error.message : '清理图片文字索引失败')
+    } finally {
+      setBusyScope(null)
+    }
+  }
+
   const openKnowledge = async (): Promise<void> => {
     setBusyScope('knowledge-directory')
     try {
@@ -134,9 +173,14 @@ export function CacheCleanupPage({
                   <Button
                     variant="outline"
                     size="sm"
+                    data-testid={`cache-clear-${item.id}`}
                     disabled={busyScope !== null}
                     aria-busy={busyScope === item.id}
-                    onClick={() => void clear(item.id)}
+                    onClick={() =>
+                      item.id === 'image-text-index'
+                        ? setConfirmingScope('image-text-index')
+                        : void clear(item.id)
+                    }
                   >
                     {busyScope === item.id ? '清理中...' : '清理'}
                   </Button>
@@ -169,6 +213,41 @@ export function CacheCleanupPage({
           </div>
         </div>
       </div>
+
+      {/* 图片文字索引是「重新建立成本很高」的派生数据，必须二次确认并写清不可逆的范围。 */}
+      <AlertDialog
+        open={confirmingScope === 'image-text-index'}
+        onOpenChange={(open) => setConfirmingScope(open ? 'image-text-index' : null)}
+      >
+        <AlertDialogContent>
+          <AlertDialogHeader>
+            <AlertDialogTitle>清理图片文字索引？</AlertDialogTitle>
+            <AlertDialogDescription>
+              将删除 TraceMemo 本地生成的图片 OCR 文本和对应搜索索引。
+            </AlertDialogDescription>
+          </AlertDialogHeader>
+          <div className="settings-confirm-detail">
+            <p>不会删除：</p>
+            <ul>
+              <li>微信原始图片</li>
+              <li>微信聊天记录</li>
+              <li>普通文字知识库</li>
+              <li>微信数据库</li>
+            </ul>
+            <p>清理后，「问问微信」将无法搜索图片中的文字；之后可以重新建立。</p>
+          </div>
+          <AlertDialogFooter>
+            <AlertDialogCancel>取消</AlertDialogCancel>
+            <AlertDialogAction
+              data-testid="cache-clear-image-text-index-confirm"
+              className="bg-destructive text-destructive-foreground hover:bg-destructive/90"
+              onClick={() => void clearImageTextIndex()}
+            >
+              确认清理
+            </AlertDialogAction>
+          </AlertDialogFooter>
+        </AlertDialogContent>
+      </AlertDialog>
     </div>
   )
 }
diff --git a/src/renderer/src/styles/search.scss b/src/renderer/src/styles/search.scss
index 1df01da..f1f8e93 100644
--- a/src/renderer/src/styles/search.scss
+++ b/src/renderer/src/styles/search.scss
@@ -278,6 +278,33 @@
   line-height: 15px;
 }
 
+/* 「建立图片文字索引」确认弹窗的正文：侧栏卡片用的 10px 在弹窗里太挤，
+   这里单独给一档更大的字号，并保持与卡片一致的次要文字色。 */
+.ai-search-knowledge-confirm {
+  display: flex;
+  flex-direction: column;
+  gap: 8px;
+  color: var(--wxex-text-muted);
+  font-size: 12px;
+  line-height: 19px;
+
+  p {
+    margin: 0;
+  }
+
+  strong {
+    color: var(--wxex-text-primary);
+  }
+
+  ul {
+    margin: 0;
+    padding-left: 18px;
+    display: flex;
+    flex-direction: column;
+    gap: 3px;
+  }
+}
+
 .ai-search-knowledge-error {
   color: var(--wxex-warning);
 }
diff --git a/src/renderer/src/styles/settings-preferences.scss b/src/renderer/src/styles/settings-preferences.scss
index d593fe5..7efccc6 100644
--- a/src/renderer/src/styles/settings-preferences.scss
+++ b/src/renderer/src/styles/settings-preferences.scss
@@ -79,6 +79,29 @@
   }
 }
 
+/* 清理类确认弹窗的正文（「不会删除……」清单）。
+   侧栏卡片那种 10px 在弹窗里太小，这里单独给一档。 */
+.settings-confirm-detail {
+  display: flex;
+  flex-direction: column;
+  gap: 8px;
+  color: var(--wxex-text-muted);
+  font-size: 12px;
+  line-height: 19px;
+
+  p {
+    margin: 0;
+  }
+
+  ul {
+    margin: 0;
+    padding-left: 18px;
+    display: flex;
+    flex-direction: column;
+    gap: 3px;
+  }
+}
+
 .voice-runtime-card dl {
   display: grid;
   grid-template-columns: repeat(3, minmax(0, 1fr));
diff --git a/src/shared/cache.ts b/src/shared/cache.ts
index 4d61098..ede3f79 100644
--- a/src/shared/cache.ts
+++ b/src/shared/cache.ts
@@ -1,7 +1,12 @@
-export type CacheClearScope = 'bootstrap' | 'electron' | 'knowledge' | 'all'
+export type CacheClearScope =
+  | 'bootstrap'
+  | 'electron'
+  | 'knowledge'
+  | 'image-text-index'
+  | 'all'
 
 export interface CacheSummaryItem {
-  id: 'bootstrap' | 'electron' | 'knowledge'
+  id: 'bootstrap' | 'electron' | 'knowledge' | 'image-text-index'
   label: string
   description: string
   sizeBytes: number
diff --git a/src/shared/image-text-index.ts b/src/shared/image-text-index.ts
new file mode 100644
index 0000000..7b1ef39
--- /dev/null
+++ b/src/shared/image-text-index.ts
@@ -0,0 +1,427 @@
+/**
+ * 图片文字索引（Image OCR Derived Text）契约。
+ *
+ * 硬规则（与语音转写同源的设计约束）：
+ * - 微信图片消息是 **authoritative source**，OCR 文本是 **derived content**。
+ * - OCR 文本绝不写回原始消息、绝不修改 WCDB、绝不伪装成用户发送的文字消息。
+ * - OCR 命中时 Evidence 必须回到**原始图片消息**，而不是一条虚构的 OCR 消息。
+ *
+ * 因此这里刻意分成两层：
+ * 1. `ImageOcrArtifact` —— 按「图片内容 + OCR 运行时指纹」去重的派生文本（可能一张图被转发到多个会话）。
+ * 2. `ImageOcrBinding`  —— 「某个会话里的某条图片消息 → 某个 artifact」的绑定，保证去重不丢来源。
+ */
+
+/** 派生文本的引擎标识；与 System OCR 的引擎常量保持一致。 */
+export const IMAGE_TEXT_INDEX_ENGINE = 'windows-system-ocr'
+
+/** 派生库自身的 schema 版本（与 Knowledge 的 schema 相互独立）。 */
+export const IMAGE_TEXT_INDEX_SCHEMA_VERSION = 1
+
+/**
+ * OCR 并发上限。
+ *
+ * 当前实现**严格串行**（循环体内只有一次 await，无 Promise.all 扇出），等价于 1。
+ * 这个常量是后续调高的唯一入口：Windows OCR 是进程内 WinRT 调用，实测单张
+ * 20–40ms，串行已足够；调高只会和 Query Agent 抢 CPU。
+ */
+export const DEFAULT_IMAGE_TEXT_OCR_CONCURRENCY = 1
+
+/** 每个批次的图片条数；批间让出 event loop，保证 UI / 查询不被卡住。 */
+export const IMAGE_TEXT_INDEX_BATCH_SIZE = 12
+
+/** 已完成一批之后、回到会话循环前的让出时间。 */
+export const IMAGE_TEXT_INDEX_YIELD_MS = 0
+
+/** 单张图片的 OCR 结果状态。 */
+export type ImageOcrState =
+  /** 尚未处理 */
+  | 'pending'
+  /** 正在处理（进程中断后会回到 pending） */
+  | 'processing'
+  /** 成功识别出文字 */
+  | 'indexed'
+  /** 成功识别，但图片里没有文字（表情包 / 风景 / 头像…）——这是**正常终态**，不重试 */
+  | 'empty'
+  /** 图片消息本身缺少定位字段（md5 / datName），无法找到文件 */
+  | 'metadata_missing'
+  /** 图片文件已不存在（微信清理过原图与缩略图）——**正常终态**，不是 OCR 失败 */
+  | 'image_missing'
+  /**
+   * 解密服务不可用（运行时环境问题）。
+   *
+   * **这不是单张图片的失败** —— 它意味着整条流水线的前置依赖缺失。
+   * 它的存在会阻断 `complete`，并且正常流程应该在 preflight 就拦下、根本不写这种状态。
+   */
+  | 'decrypt_unavailable'
+  /** 找到了文件，但解密失败（密钥/账号上下文不对，或文件损坏） */
+  | 'decrypt_failed'
+  /** 解密产出无法识别为图片格式（解码失败） */
+  | 'decode_failed'
+  /** 解码成功，但 OCR 执行失败 */
+  | 'ocr_failed'
+  /** 用户取消时正在处理 */
+  | 'cancelled'
+
+/**
+ * 可以落库的状态。
+ *
+ * `processing` 是瞬态的（只存在于一次 pass 的内存里）：进程崩溃后它没有任何意义，
+ * 而且它绝不允许进入 Knowledge 索引 —— Knowledge 只应该看到"已定态"。
+ */
+export type ImageOcrPersistedState = Exclude<ImageOcrState, 'processing'>
+
+/** 终态集合：落在这里的状态不会在下次 pass 被自动重试。 */
+export const IMAGE_OCR_TERMINAL_STATES: readonly ImageOcrState[] = [
+  'indexed',
+  'empty',
+  'metadata_missing',
+  'image_missing',
+  'decrypt_failed',
+  'decode_failed',
+  'ocr_failed',
+  'cancelled'
+]
+
+/**
+ * 运行时不可用态：**不是**单张图片的终态。
+ *
+ * 它与终态分开，是为了让「这 4.5 万张都失败了」永远不能被当成"该条已处理"。
+ */
+export const IMAGE_OCR_RUNTIME_UNAVAILABLE_STATES: readonly ImageOcrState[] = [
+  'decrypt_unavailable'
+]
+
+export function isTerminalImageOcrState(state: ImageOcrState): boolean {
+  return IMAGE_OCR_TERMINAL_STATES.includes(state)
+}
+
+export function isRuntimeUnavailableImageOcrState(state: ImageOcrState): boolean {
+  return IMAGE_OCR_RUNTIME_UNAVAILABLE_STATES.includes(state)
+}
+
+/**
+ * **可重试的失败态**。
+ *
+ * 代码修好之后，这些状态的记录可以安全地重跑 —— 它们要么是运行时依赖缺失，
+ * 要么是"当时环境不对"造成的失败。重置只删这些绑定与它们的 checkpoint，
+ * 成功记录（indexed / empty）一条都不动。
+ */
+export const IMAGE_OCR_RETRIABLE_FAILURE_STATES: readonly ImageOcrPersistedState[] = [
+  'decrypt_unavailable',
+  'decrypt_failed',
+  'decode_failed',
+  'ocr_failed'
+]
+
+/**
+ * OCR 运行时指纹。
+ *
+ * 缓存身份**不能只是图片 hash**：换 OCR 引擎 / 升级运行时 / 换语言配置之后
+ * 必须允许重新识别，否则用户会永远拿到旧引擎的结果。
+ */
+export interface ImageOcrProvenance {
+  engine: string
+  platform: string
+  runtimeVersion: string | null
+  /** 实际使用的 OCR 语言标签；null 表示由系统用户语言决定。 */
+  language: string | null
+}
+
+/**
+ * artifact 去重键 = 图片内容身份 + OCR 运行时指纹。
+ *
+ * 刻意不包含 conversationId / messageId —— 同一张图片被转发到多个会话时，
+ * OCR 只算一次，但会有多条 binding 指向同一个 artifact。
+ */
+export function buildImageOcrArtifactKey(input: {
+  imageIdentity: string
+  provenance: ImageOcrProvenance
+}): string {
+  const { imageIdentity, provenance } = input
+  return [
+    imageIdentity,
+    provenance.engine,
+    provenance.platform,
+    provenance.runtimeVersion ?? 'unknown',
+    provenance.language ?? 'auto'
+  ].join('|')
+}
+
+/** 派生文本记录（按 artifact key 唯一）。 */
+export interface ImageOcrArtifact {
+  accountId: string
+  artifactKey: string
+  imageIdentity: string
+  state: ImageOcrPersistedState
+  /** OCR 正文；`empty` 状态为空串。 */
+  text: string
+  charCount: number
+  engine: string
+  platform: string
+  runtimeVersion: string | null
+  language: string | null
+  /** 只在失败时写入；用于诊断，绝不包含 OCR 正文。 */
+  errorCode?: string
+  createdAt: number
+  updatedAt: number
+}
+
+/** 「某会话的某条图片消息」到 artifact 的绑定。 */
+export interface ImageOcrBinding {
+  accountId: string
+  conversationId: string
+  messageId: string
+  /** Unix epoch **毫秒**（Knowledge 契约统一用毫秒）。 */
+  createTime: number
+  senderId?: string
+  senderName?: string
+  /** 图片内容身份（去重维度 1）。 */
+  imageIdentity: string
+  /**
+   * 指向的 artifact（内容身份 + OCR 运行时指纹）。
+   *
+   * 必须携带完整 artifact key 而不是只存 imageIdentity：换了 OCR 引擎/运行时之后
+   * 同一张图会有多个 artifact，绑定必须能精确指到"这次用哪个指纹算出来的文本"。
+   */
+  artifactKey: string
+  state: ImageOcrPersistedState
+  updatedAt: number
+}
+
+/** 索引任务运行态。 */
+export type ImageTextIndexRunState =
+  | 'idle'
+  | 'counting'
+  | 'running'
+  | 'paused'
+  | 'completed'
+  | 'cancelled'
+  | 'error'
+
+/** 进度（面向 UI；只含数字与状态，绝不含 OCR 正文 / 路径 / wxid）。 */
+export interface ImageTextIndexProgress {
+  state: ImageTextIndexRunState
+  /** 检测到的图片消息总数（SQL 统计，未解密）。 */
+  totalImageMessages: number
+  processed: number
+  indexed: number
+  empty: number
+  missing: number
+  failed: number
+  /** 运行时不可用（如解密服务缺失）；不计入 processed，且会阻断 complete。 */
+  runtimeUnavailable: number
+  /** 系统性失败（处理过但一条都没成功）——UI 必须显示"异常"而不是"已建立"。 */
+  systemicFailure: boolean
+  pending: number
+  /** 0–100，保留 1 位小数；未完成时封顶 99.9。 */
+  percent: number
+  /** 处理进度百分比（与 percent 同源，语义化别名）。 */
+  processedPercent: number
+  startedAt?: number
+  updatedAt: number
+  cancellable: boolean
+  paused: boolean
+  lastError?: string
+}
+
+/**
+ * 图片文字索引的覆盖度 —— **独立的覆盖维度**。
+ *
+ * 文字消息索引 100% 不代表图片文字可用；Query Agent 必须能单独看到这一维。
+ */
+export interface ImageTextIndexCoverage {
+  totalImageMessages: number
+  /** 已进入**非运行时**终态的条数（indexed + empty + missing + failed）。 */
+  processed: number
+  indexed: number
+  empty: number
+  missing: number
+  failed: number
+  /**
+   * 运行时不可用（如解密服务缺失）的条数。
+   *
+   * 单独一列、**不计入 processed**：它代表"流水线前置依赖缺失"，
+   * 绝不能与"这条图片已经处理过了"混为一谈。
+   */
+  runtimeUnavailable: number
+  pending: number
+  /** 是否建立过（有落盘统计且处理过）。 */
+  established: boolean
+  /** 是否**真正**覆盖完整（分母可信 + 无 pending + 无运行时不可用 + 不是"全军覆没"）。 */
+  complete: boolean
+  /**
+   * 系统性失败：处理过一批，但 indexed / empty / missing 全为 0、失败却不为 0。
+   *
+   * 这就是"4.5 万张全部失败、却告诉用户已建立"那种情况的判据 ——
+   * 它必须阻断 `complete`，并让 UI 显示"异常"。
+   */
+  systemicFailure: boolean
+  /**
+   * `totalImageMessages` 的统计时刻（epoch ms）；null = 从未统计过。
+   *
+   * 必须有这个时间戳：total 是**某一时刻**的 SQL 统计，之后微信里新增的图片
+   * 还没进索引。只说"已覆盖全部 N 条"而不给统计时刻，就是在把「当时完整」
+   * 冒充成「现在完整」。
+   */
+  countedAt: number | null
+}
+
+/** 覆盖度状态（外加"未建立"）。UI 与 Query Agent 共用同一判据，避免两处各推一套口径漂移。 */
+export type ImageTextCoverageState = 'not_built' | 'partial' | 'complete' | 'failed'
+
+export function imageTextCoverageState(coverage: ImageTextIndexCoverage): ImageTextCoverageState {
+  if (!coverage.established) return 'not_built'
+  if (coverage.systemicFailure) return 'failed'
+  return coverage.complete ? 'complete' : 'partial'
+}
+
+/**
+ * 处理进度百分比。
+ *
+ * 保留 1 位小数，且**未完成时封顶 99.9%**：
+ * `Math.round(45479 / 45707 * 100)` 会得到 `100`，于是出现了"已建立 · 仅完成 100%"
+ * 这种自相矛盾的显示。进度条可以近似，结论句不行。
+ */
+export function imageTextProcessedPercent(processed: number, total: number): number {
+  if (!(total > 0)) return 0
+  const raw = (processed / total) * 100
+  if (raw >= 100) return 100
+  return Math.min(99.9, Math.round(raw * 10) / 10)
+}
+
+/** 覆盖度的人话结论，供 Query Agent / UI 直接引用。 */
+export function describeImageTextCoverage(coverage: ImageTextIndexCoverage): string {
+  if (!coverage.established) {
+    return '图片文字索引尚未建立：目前只能搜索文字消息，图片里的文字还搜不到。'
+  }
+  if (coverage.systemicFailure) {
+    return `图片文字索引当前异常：已处理的 ${coverage.processed.toLocaleString()} 条图片消息全部失败（成功识别 0 条、无文字 0 条、图片缺失 0 条）。当前无法搜索图片中的文字。`
+  }
+  if (coverage.complete) {
+    return `图片文字索引已覆盖全部 ${coverage.totalImageMessages.toLocaleString()} 条图片消息。`
+  }
+  const percent = imageTextProcessedPercent(coverage.processed, coverage.totalImageMessages)
+  return `图片文字索引只完成 ${percent}%（${coverage.processed.toLocaleString()} / ${coverage.totalImageMessages.toLocaleString()} 条图片消息），当前图片搜索结果可能不完整。`
+}
+
+/** 快速统计结果（不含解密）。 */
+export interface ImageTextIndexCountResult {
+  totalImageMessages: number
+  scannedConversations: number
+  /**
+   * 统计失败（拿不到数）的会话数。
+   *
+   * 必须与 `totalImageMessages = 0` 区分开：**"一张图片都没有"和"根本没数成"是两件事**。
+   * 把后者显示成 0 会让用户以为账号里没有图片，从而放弃建立索引 —— 这正是本功能
+   * 一直在避免的那类谎话。
+   */
+  failedConversations: number
+  /** 实际用于判定"这是图片消息"的列名；null = 一个会话都没探测到。 */
+  typeColumn: string | null
+  /** 失败原因摘要（仅供诊断，不含用户数据）。 */
+  error?: string
+  durationMs: number
+}
+
+/**
+ * 单个会话的图片消息计数探针。
+ *
+ * `count: null` = **统计失败**，不等于 0 张。调用方必须区分处理。
+ */
+export interface ImageMessageCountProbe {
+  count: number | null
+  /** 实际用于判定图片消息的类型列名。 */
+  typeColumn: string | null
+  /** 失败原因摘要（不含任何用户内容）。 */
+  error?: string
+}
+
+/**
+ * 会话级增量水位。
+ *
+ * 刻意用 **两个** 判据而不是只比 count：
+ * - `count` 能发现大多数增删；
+ * - `maxLocalId`（消息插入序的最大值）能发现「总数相同但集合变了」——
+ *   例如撤回一张旧图的同时新增一张新图，count 不变但新图的 local_id 更大。
+ *
+ * 只用 count 会静默漏掉新图片；只用 create_time 会被「后到的旧时间消息」
+ * （网络延迟 / 消息恢复 / 合并转发回填）骗过。`local_id` 是 WCDB 行内单调的
+ * 插入序，对 append 与「等量替换」两种情况都成立。
+ */
+export interface ImageMessageWatermark {
+  count: number
+  /** 该会话图片消息的最大插入序；没有图片时为 0。 */
+  maxLocalId: number
+}
+
+/**
+ * 派生索引修复的结果。
+ *
+ * 分层前提（任何一层都不许越界去动上一层）：
+ * - L1 Image OCR Artifact —— 昂贵，持久化，**尽量永不重复计算**
+ * - L2 Message Binding —— 便宜，可修复
+ * - L3 Knowledge Derived Entry / FTS —— 便宜，可重建
+ * - L4 Query Agent / Evidence —— 查询层，只读
+ *
+ * 修 L2/L3/L4 **绝不能**自动清 L1。`ocrExecutions` 因此被写死成字面量 `0`：
+ * 修复路径一旦开始调 OCR，类型就不再成立，编译期就会拦下来。
+ */
+export interface ImageTextIndexRepairResult {
+  /** 实际重建了派生索引的会话数。 */
+  conversations: number
+  /** 永远是 0 —— 修复路径禁止触发 OCR（这一条是契约，不是观察值）。 */
+  ocrExecutions: 0
+  durationMs: number
+  /** 索引任务正在运行时拒绝并发修复（避免读到半程 binding）。 */
+  skipped: boolean
+}
+
+/** 派生数据占用（设置 → 缓存与清理）。 */
+export interface ImageTextIndexStorageStats {
+  indexedImages: number
+  ocrTextCount: number
+  totalBytes: number
+  updatedAt: number | null
+}
+
+/** 索引过程中用于写入派生库的单条结果。 */
+export interface ImageOcrWriteInput {
+  accountId: string
+  conversationId: string
+  messageId: string
+  createTime: number
+  senderId?: string
+  senderName?: string
+  /** 已解密的图片内容身份；取不到图片时为 null。 */
+  imageIdentity: string | null
+  state: ImageOcrPersistedState
+  text: string
+  provenance: ImageOcrProvenance
+  errorCode?: string
+}
+
+/** 索引服务的启动参数。 */
+export interface ImageTextIndexStartOptions {
+  /** 只处理前 N 个会话，用于受控 smoke；不传 = 全量。 */
+  conversationLimit?: number
+  /** 只处理前 N 条图片消息，用于受控 smoke。 */
+  messageLimit?: number
+  /**
+   * 只处理这个时刻（epoch ms）**之后**的图片消息；不传 = 全部历史。
+   *
+   * 存在的意义是**可验证性**：几万张图片的全量回填没法用来排查问题，
+   * 先跑"最近一天"这种小窗口才能证明链路是通的。
+   * 带窗口运行时会**跳过增量跳过逻辑**（每次都重扫窗口内的消息），
+   * 因为 checkpoint 是围绕全量集合建立的，混用会让"跳过"变得不可解释。
+   */
+  sinceMs?: number
+}
+
+/** 对外状态快照（问问微信卡片 / 设置清理页共用同一份）。 */
+export interface ImageTextIndexStatus {
+  progress: ImageTextIndexProgress
+  coverage: ImageTextIndexCoverage
+  storage: ImageTextIndexStorageStats
+  /** 正在做「检测到多少条图片消息」的 SQL 统计。 */
+  counting: boolean
+}
diff --git a/src/shared/knowledge.ts b/src/shared/knowledge.ts
index e9539a9..cfdedcf 100644
--- a/src/shared/knowledge.ts
+++ b/src/shared/knowledge.ts
@@ -42,8 +42,30 @@ export interface KnowledgeSourceMessage {
   voiceTranscript?: string
   /** Local coverage state only. Error text is never copied into the index. */
   voiceTranscriptState?: 'pending' | 'transcribed' | 'failed'
+  /**
+   * 图片里的文字（本地 System OCR 的派生结果）。
+   *
+   * 与 voiceTranscript 同构：这是 **derived content**，原图片消息仍然是
+   * authoritative source。它绝不写回 message.body，也绝不产生"OCR 消息"。
+   */
+  imageOcrText?: string
+  /** 图片 OCR 的本地状态；与 voiceTranscriptState 一样不含错误正文。 */
+  imageOcrState?: KnowledgeImageOcrState
 }
 
+/** 图片 OCR 的本地覆盖状态（错误详情绝不进索引）。 */
+export type KnowledgeImageOcrState =
+  | 'pending'
+  | 'indexed'
+  | 'empty'
+  | 'metadata_missing'
+  | 'image_missing'
+  | 'decrypt_unavailable'
+  | 'decrypt_failed'
+  | 'decode_failed'
+  | 'ocr_failed'
+  | 'cancelled'
+
 export interface KnowledgeNormalizedMessage extends KnowledgeSourceMessage {
   searchableText: string
   contentHash: string
@@ -194,9 +216,38 @@ export interface KnowledgeEvidence {
   /** The source type belongs to the original message, not the retrieval method. */
   sourceKind: KnowledgeMessageKind
   text: string
+  /**
+   * 这条证据里「从图片里读出来的文字」（本地 System OCR 的派生结果）。
+   *
+   * 只用于**来源解释**：让用户/模型知道这段内容来自图片，而不是群友真的发了一条文字消息。
+   * authoritative source 始终是原始图片消息 —— 这里不产生任何"OCR 消息"。
+   */
+  imageOcrText?: string
+  /**
+   * 命中所依赖的**派生来源**。
+   *
+   * 有值 = 这条结果依赖本地派生内容才能命中（而不是原始消息本身的文字）。
+   * 与 `sourceKind` 正交：`sourceKind` 说的是原始消息是什么，这里说的是"靠什么搜到的"。
+   */
+  derivedSource?: 'image_ocr'
   score?: number
 }
 
+/**
+ * 证据文本面向用户 / 模型时的可读化处理。
+ *
+ * `searchableText` 里的 `图片文字：` 只是索引期用来区分派生内容的内部标签，
+ * 它**绝不能出现在 Evidence 里**：用户不该看到引擎内部前缀，
+ * 而且"这段文字来自图片"应该由结构化的来源标记表达，而不是靠一个冒号前缀。
+ */
+export function toEvidenceDisplayText(searchableText: string): string {
+  return searchableText
+    .split('\n')
+    .map((line) => line.replace(/^\s*(?:图片文字|OCR|system-ocr)\s*[：:]\s*/i, ''))
+    .join('\n')
+    .trim()
+}
+
 export interface KnowledgeVoiceCoverage {
   voiceMessageCount: number
   transcribedVoiceCount: number
diff --git a/src/shared/local-query-api.ts b/src/shared/local-query-api.ts
index 0a51bb3..255aa0b 100644
--- a/src/shared/local-query-api.ts
+++ b/src/shared/local-query-api.ts
@@ -112,6 +112,21 @@ export interface QueryEvidenceItem
   /** 该证据所属会话的展示名（群名 / 联系人名）。 */
   conversationName?: string
   conversationType?: 'user' | 'group'
+  /**
+   * 命中所依赖的**派生来源**（与 `sourceKind` 正交）。
+   *
+   * 有值时 Evidence UI 加一个轻量来源标记（如「图片文字」），
+   * 让用户知道这段内容来自**图片里的文字**，而不是群友真的发了一条文字消息。
+   * authoritative source 仍然是原始图片消息，`messageRef` 也仍然指向原图。
+   */
+  derivedSource?: 'image_ocr'
+  /**
+   * 「从图片里读出来的文字」片段，只用作命中解释。
+   *
+   * 刻意与 `text` 分开：`text` 是这条消息的内容，这里只回答"命中是因为图里的哪段文字"。
+   * 普通文字消息不会有这个字段。
+   */
+  imageOcrText?: string
 }
 
 /**
@@ -217,6 +232,28 @@ export interface QueryMessage {
     url?: string
     sizeBytes?: number
   }
+  /**
+   * 图片 OCR 派生文本（**仅**图片消息、且本地已识别出文字时存在）。
+   *
+   * 它是 derived content，不是消息正文：这条消息的正文仍然是空的"图片附件"，
+   * authoritative evidence 也仍然是**原始图片消息**（`messageRef` 指向它）。
+   * 之所以必须单独一个字段而不是塞进 `text`：一旦混进去，模型与 UI 就无法区分
+   * "群友发了一段文字"和"图片里识别出这段文字"，而这正是本功能的诚实性前提。
+   */
+  imageOcrText?: string
+  /** 派生来源语义：`image_ocr` = 这段文字来自图片识别，而不是原始文字消息。 */
+  derivedSource?: 'image_ocr'
+  /**
+   * 这条图片消息在本地图片文字索引里的状态。
+   *
+   * - `indexed`：识别过且有文字（此时 `imageOcrText` 有值）
+   * - `empty`：识别过，但图里确实没有文字 —— 这是**已知结论**，不是"没索引"
+   * - `not_indexed`：尚未进入索引（未建立 / 还没处理到 / 已被清理）
+   *
+   * 区分这三者是硬要求：`not_indexed` 不允许被当成"图里没内容"，
+   * `empty` 也不允许被当成"可以凭画面猜内容"（OCR 不是 Vision）。
+   */
+  imageTextState?: 'indexed' | 'empty' | 'not_indexed'
 }
 export interface QueryMessagesResponse {
   status: string
@@ -228,6 +265,14 @@ export interface QueryMessagesResponse {
   candidates?: Array<{ displayName: string; type: 'user' | 'group' }>
   /** 本次实际使用的语料边界。 */
   scope?: ResolvedCorpusScope
+  /**
+   * 图片文字索引的覆盖度。
+   *
+   * 与 `search_messages` 同源同口径 —— 精确读消息这条路径同样必须知道
+   * "图片里的文字到底索引了多少"，否则模型在图片文字尚未索引时
+   * 只能看到一个光秃秃的 `attachment`，进而把"索引缺口"说成"图片没有文字"。
+   */
+  imageOcrCoverage?: QueryImageTextCoverage
 }
 export interface SearchMessagesRequest {
   target: QueryTarget
@@ -279,6 +324,13 @@ export interface SearchMessagesResponse {
    * **本地时间**与结论，模型只需引用，不需要自己判断，也不需要输出 epoch 数字。
    */
   indexCoverage?: QueryIndexCoverage
+  /**
+   * 图片文字索引覆盖度（**独立于**文字索引的维度）。
+   *
+   * `state !== 'complete'` 时，涉及图片/截图/海报的问题**不允许**因为 0 条证据
+   * 就回答"没有"——必须说明图片文字索引尚未完成、当前结果无法覆盖全部图片。
+   */
+  imageOcrCoverage?: QueryImageTextCoverage
   /** 本次检索的真实耗时分解（ADDITIVE，用于诊断与 UI 展示；不进入模型上下文）。 */
   timings?: QuerySearchTimings
 }
@@ -294,6 +346,33 @@ export interface QueryIndexCoverage {
   summary: string
 }
 
+/**
+ * 图片文字索引（本地 OCR 派生文本）的覆盖度 —— 与文字索引覆盖度**互相独立**。
+ *
+ * 为什么必须单独一个维度：文字消息索引 100% 不代表图片里的文字可被搜索。
+ * 图片 OCR 是用户确认后才建立的重活，可能"未建立"，也可能"只做了 30%"。
+ * 这时如果模型因为 0 条证据就回答"没有"，就是把**索引缺口**说成了**事实空缺**。
+ */
+export interface QueryImageTextCoverage {
+  /**
+   * `failed` = 索引**当前异常**（处理过一批但一条都没成功，或运行时依赖缺失）。
+   *
+   * 它与 `partial` 都必须让 Query Agent 拒绝凭零结果下"没有"的结论。
+   */
+  state: 'not_built' | 'partial' | 'complete' | 'failed'
+  totalImageMessages: number
+  processed: number
+  indexed: number
+  empty: number
+  missing: number
+  failed: number
+  pending: number
+  /** 图片数量统计时刻（本地时间 `MM-DD HH:mm`）；从未统计时为 undefined。 */
+  countedAtLabel?: string
+  /** 可直接引用的结论句；模型只引用，不要自己换算或推断。 */
+  summary: string
+}
+
 /**
  * `search_messages` 的真实耗时分解（ADDITIVE 诊断字段）。
  *
@@ -346,6 +425,13 @@ export interface ConversationOverviewResponse {
   evidence?: QueryEvidenceItem[]
   candidates?: Array<{ displayName: string; type: 'user' | 'group' }>
   scope?: ResolvedCorpusScope
+  /**
+   * 图片文字索引覆盖度（**独立维度**，与 `voiceCoverage` 平级）。
+   *
+   * 会话概览以源数据为准，所以能如实反映"这段时间聊了什么"；但"图片里的文字"
+   * 只存在于本地 OCR 派生索引里，概览的完整性**不覆盖**这一维。
+   */
+  imageOcrCoverage?: QueryImageTextCoverage
   /**
    * 证据来源：`wcdb` = 直接读源数据（会话概览的事实来源）；`knowledge` = 派生索引。
    * 派生索引可能滞后，故概览以源数据为准。
diff --git a/src/shared/query-agent.ts b/src/shared/query-agent.ts
index 99543ff..079b566 100644
--- a/src/shared/query-agent.ts
+++ b/src/shared/query-agent.ts
@@ -33,6 +33,15 @@ export interface AskWechatEvidenceItem {
   timestamp?: number
   messageType?: string
   text?: string
+  /**
+   * 命中所依赖的派生来源（与 `messageType` 正交）。
+   *
+   * `image_ocr` = 这条结果靠**图片里的文字**命中，而不是群友真的发了一条文字消息。
+   * Evidence UI 会据此显示轻量来源标记。authoritative source 仍是原始图片消息。
+   */
+  derivedSource?: 'image_ocr'
+  /** 「从图片里读出来的文字」片段，只作命中解释（普通文字消息不会有）。 */
+  imageOcrText?: string
   attachment?: { kind?: string; name?: string; url?: string; sizeBytes?: number }
   /** 产生这条证据的 Tool（诊断 / 分组）。 */
   source: string
@@ -133,6 +142,24 @@ export interface QueryAgentDiagnostics {
   tools: string[]
   totalMs: number
   outcome: AskWechatOutcome
+  /**
+   * 本次查询里**实际取到 OCR 派生文本**的图片消息/证据条数（诊断，不含正文）。
+   *
+   * `0` 配合 `tools` 就能区分两种完全不同的故障：
+   * 图片文字索引没建（索引问题），还是建好了但查询路径没接上（链路问题）。
+   */
+  imageOcrTextCount?: number
+  /** 本次查询里图片文字索引的覆盖度状态（`not_built` / `partial` / `complete` / `failed`）。 */
+  imageOcrCoverageState?: string
+  /**
+   * 用户问题原文。
+   *
+   * 这一条**刻意**包含聊天内容：排查"同一个问题为什么这次答对上次答错"必须知道问的是什么。
+   * 日志只写在用户本机的应用日志目录（设置 → 检索诊断里可查看 / 清空），不上传、不进遥测。
+   */
+  question?: string
+  /** 模型最终回答原文（同上，仅本地日志，用于排查）。 */
+  answer?: string
 }
 
 export type AskWechatOutcome =
diff --git a/tests/component/ai-search-cache-consent.test.tsx b/tests/component/ai-search-cache-consent.test.tsx
index 052c5db..4e51a48 100644
--- a/tests/component/ai-search-cache-consent.test.tsx
+++ b/tests/component/ai-search-cache-consent.test.tsx
@@ -7,6 +7,7 @@ import {
   buildSearchCacheKey
 } from '../../src/renderer/src/components/search/searchUtils'
 import { makePipelineEvidence, makeSearchResult } from './support/ai-search-fixtures'
+import { makeImageTextIndexApi } from './support/image-text-index-api'
 
 const api = {
   getSettings: vi.fn(),
@@ -17,7 +18,9 @@ const api = {
   getAiSearchProviderStatus: vi.fn(),
   authorizeAiSearchExternalProvider: vi.fn(),
   runAiSearch: vi.fn(),
-  cancelAiSearch: vi.fn()
+  cancelAiSearch: vi.fn(),
+  // 侧栏新增的「图片文字索引」卡片会读这些桥接。
+  ...makeImageTextIndexApi()
 }
 
 describe('AISearchWorkspace cache privacy boundary', () => {
diff --git a/tests/component/ai-search-query-agent.test.tsx b/tests/component/ai-search-query-agent.test.tsx
index 2d7dc46..09d0d86 100644
--- a/tests/component/ai-search-query-agent.test.tsx
+++ b/tests/component/ai-search-query-agent.test.tsx
@@ -3,6 +3,7 @@ import { act, render, screen } from '@testing-library/react'
 import userEvent from '@testing-library/user-event'
 import { AISearchWorkspace } from '../../src/renderer/src/components/search/AISearchWorkspace'
 import { aiSearchContact, aiSearchGroup, makeSearchResult } from './support/ai-search-fixtures'
+import { makeImageTextIndexApi } from './support/image-text-index-api'
 import type { AskWechatQueryResult, AskWechatStats, QueryAgentProgressEvent } from '../../src/shared/query-agent'
 
 type AnsweredResult = Extract<AskWechatQueryResult, { status: 'answered' }>
@@ -25,7 +26,9 @@ const api = {
   runAskWechatQuery: vi.fn(),
   forgetAskWechatConversation: vi.fn(),
   onAskWechatProgress: vi.fn(),
-  cancelKnowledgeIndex: vi.fn()
+  cancelKnowledgeIndex: vi.fn(),
+  // 侧栏新增的「图片文字索引」卡片会读这些桥接。
+  ...makeImageTextIndexApi()
 }
 
 const indexLatestAt = new Date('2026-09-11T11:57:24+08:00').getTime()
diff --git a/tests/component/ai-search-workspace-regression.test.tsx b/tests/component/ai-search-workspace-regression.test.tsx
index 6a0159d..4f82a79 100644
--- a/tests/component/ai-search-workspace-regression.test.tsx
+++ b/tests/component/ai-search-workspace-regression.test.tsx
@@ -14,6 +14,7 @@ import {
   makePipelineEvidence,
   makeSearchResult
 } from './support/ai-search-fixtures'
+import { makeImageTextIndexApi } from './support/image-text-index-api'
 
 const api = {
   getSettings: vi.fn(),
@@ -28,7 +29,9 @@ const api = {
   startKnowledgeIndex: vi.fn(),
   writeAppLog: vi.fn(),
   revealAppLog: vi.fn(),
-  copyText: vi.fn()
+  copyText: vi.fn(),
+  // 侧栏新增的「图片文字索引」卡片会读这些桥接；漏掉任何一个都会让卡片挂载即抛错。
+  ...makeImageTextIndexApi()
 }
 
 const readyKnowledgeStatus = {
diff --git a/tests/component/evidence-image-ocr-source.test.tsx b/tests/component/evidence-image-ocr-source.test.tsx
new file mode 100644
index 0000000..07760cd
--- /dev/null
+++ b/tests/component/evidence-image-ocr-source.test.tsx
@@ -0,0 +1,106 @@
+/**
+ * §1 / §17：Evidence 的「图片文字」来源语义。
+ *
+ * 三条不能退让的约束：
+ * 1. 来自图片 OCR 的命中，UI 必须有轻量来源标记（「图片文字」），
+ *    让用户知道这段内容来自图片，而不是群友真的发了一条文字消息；
+ * 2. authoritative source 仍然是**原始图片消息** —— messageRef 不变，跳转目标就是原图；
+ * 3. 引擎内部前缀（`图片文字：` / `OCR:` / `system-ocr`）绝不允许出现在用户可见文本里；
+ * 4. 普通文字消息的 Evidence 完全不受影响（不该凭空多出一个标记）。
+ */
+import { render, screen } from '@testing-library/react'
+import { describe, expect, it, vi } from 'vitest'
+import { AISearchEvidencePanel } from '../../src/renderer/src/components/search/AISearchEvidencePanel'
+import { mapAskWechatEvidence } from '../../src/renderer/src/components/search/askWechatPresentation'
+import type { EvidenceItem } from '../../src/renderer/src/components/search/searchTypes'
+import type { AskWechatEvidenceItem } from '../../src/shared/query-agent'
+import { encodeMessageRef } from '../../src/shared/local-query-api'
+
+const OCR_TEXT = 'OpenAI ChatGPT Plus $20 Pro $200'
+const IMAGE_REF = encodeMessageRef('md5-tech-group', '9001')
+const TEXT_REF = encodeMessageRef('md5-tech-group', '9002')
+
+/** Query Agent 交给渲染层的证据（图片 OCR 命中）。 */
+const imageOcrEvidence: AskWechatEvidenceItem = {
+  messageRef: IMAGE_REF,
+  conversationName: '技术交流群',
+  conversationType: 'group',
+  sender: '张三',
+  timestamp: Date.parse('2026-09-03T14:32:00+08:00'),
+  messageType: 'image',
+  // 已经由 main 侧剥掉内部前缀的可读文本
+  text: OCR_TEXT,
+  derivedSource: 'image_ocr',
+  imageOcrText: OCR_TEXT,
+  source: 'search_messages'
+}
+
+/** 普通文字消息证据（对照组）。 */
+const plainEvidence: AskWechatEvidenceItem = {
+  messageRef: TEXT_REF,
+  conversationName: '技术交流群',
+  conversationType: 'group',
+  sender: '张三',
+  timestamp: Date.parse('2026-09-03T14:30:00+08:00'),
+  messageType: 'text',
+  text: '今天正常讨论一下 API',
+  source: 'search_messages'
+}
+
+function renderPanel(evidence: EvidenceItem[]) {
+  const props: React.ComponentProps<typeof AISearchEvidencePanel> = {
+    evidence,
+    collectionCount: evidence.length,
+    selectedEvidence: 0,
+    evidenceFlash: { index: -1, nonce: 0 },
+    senderNames: {},
+    hasMoreEvidence: false,
+    onFocusEvidence: vi.fn(),
+    onJumpToEvidence: vi.fn(),
+    onLoadMoreEvidence: vi.fn(),
+    setEvidenceCardRef: vi.fn()
+  }
+  render(<AISearchEvidencePanel {...props} />)
+  return props
+}
+
+describe('图片文字 Evidence 的来源语义', () => {
+  it('映射层保留派生来源与 OCR 片段，且跳转目标仍是原始图片消息', () => {
+    const [mapped] = mapAskWechatEvidence([imageOcrEvidence])
+
+    expect(mapped.derivedSource).toBe('image_ocr')
+    expect(mapped.imageOcrText).toBe(OCR_TEXT)
+    // authoritative source = 原始图片消息：引用不变
+    expect(mapped.messageRef).toBe(IMAGE_REF)
+    expect(mapped.message.id).toBe('9001')
+    expect(mapped.contact.m_nsNickName).toBe('技术交流群')
+    expect(mapped.sourceKind).toBe('image')
+  })
+
+  it('图片 OCR 命中显示「图片文字」标记与命中解释，不泄露内部前缀', () => {
+    const evidence = mapAskWechatEvidence([imageOcrEvidence])
+    renderPanel(evidence)
+
+    const badge = screen.getByTestId('evidence-image-ocr-badge')
+    expect(badge).toBeVisible()
+    expect(badge.textContent).toBe('图片文字')
+
+    const snippet = screen.getByTestId('evidence-image-ocr-snippet')
+    expect(snippet.textContent).toContain(OCR_TEXT)
+
+    // 内部前缀绝不能出现在用户可见文本里
+    const panelText = document.body.textContent || ''
+    expect(panelText).not.toContain('图片文字：')
+    expect(panelText).not.toContain('OCR:')
+    expect(panelText).not.toContain('system-ocr')
+  })
+
+  it('普通文字消息的 Evidence 不受影响：没有来源标记，也没有 OCR 片段', () => {
+    const evidence = mapAskWechatEvidence([plainEvidence])
+    renderPanel(evidence)
+
+    expect(screen.queryByTestId('evidence-image-ocr-badge')).not.toBeInTheDocument()
+    expect(screen.queryByTestId('evidence-image-ocr-snippet')).not.toBeInTheDocument()
+    expect(screen.getByText('今天正常讨论一下 API')).toBeVisible()
+  })
+})
diff --git a/tests/component/image-text-index-card.test.tsx b/tests/component/image-text-index-card.test.tsx
new file mode 100644
index 0000000..3bfdfcd
--- /dev/null
+++ b/tests/component/image-text-index-card.test.tsx
@@ -0,0 +1,332 @@
+/**
+ * §3 / §4：「图片文字索引」卡片的用户可见行为。
+ *
+ * 这些断言对应的是产品需求里**写死的**交互契约，不是实现细节：
+ * - 未建立时先给出检测到的图片消息数量，而不是一个空洞的按钮；
+ * - 点击建立**必须先弹确认**，不允许立刻全量开跑；
+ * - 确认弹窗要写清本机执行、原图不会因识别而自动上传、可暂停、实际可识别数量取决于本地文件；
+ * - 进度只给真实数字（processed/total、识别出文字、没有文字、图片已清理、失败、百分比）；
+ * - 暂停 / 继续 / 取消三个动作都在，且暂停后能继续；
+ * - 重启后进度来自主进程快照（这里用「首帧就是 paused 快照」模拟）。
+ */
+import { act, render, screen } from '@testing-library/react'
+import userEvent from '@testing-library/user-event'
+import { beforeEach, describe, expect, it, vi } from 'vitest'
+import { ImageTextIndexCard } from '../../src/renderer/src/components/search/ImageTextIndexCard'
+import type { ImageTextIndexStatus } from '../../src/shared/image-text-index'
+
+function status(overrides: Partial<ImageTextIndexStatus> = {}): ImageTextIndexStatus {
+  return {
+    progress: {
+      state: 'idle',
+      totalImageMessages: 0,
+      processed: 0,
+      indexed: 0,
+      empty: 0,
+      missing: 0,
+      failed: 0,
+      pending: 0,
+      percent: 0,
+      updatedAt: 0,
+      cancellable: false,
+      paused: false
+    },
+    coverage: {
+      totalImageMessages: 0,
+      processed: 0,
+      indexed: 0,
+      empty: 0,
+      missing: 0,
+      failed: 0,
+      pending: 0,
+      established: false,
+      complete: false,
+      countedAt: null
+    },
+    storage: { indexedImages: 0, ocrTextCount: 0, totalBytes: 0, updatedAt: null },
+    counting: false,
+    ...overrides
+  }
+}
+
+const notBuilt = status()
+
+const running = status({
+  progress: {
+    state: 'running',
+    totalImageMessages: 12_483,
+    processed: 3842,
+    indexed: 2917,
+    empty: 412,
+    missing: 378,
+    failed: 135,
+    pending: 8641,
+    percent: 30.8,
+    updatedAt: 1,
+    cancellable: true,
+    paused: false
+  },
+  coverage: {
+    totalImageMessages: 12_483,
+    processed: 3842,
+    indexed: 2917,
+    empty: 412,
+    missing: 378,
+    failed: 135,
+    pending: 8641,
+    established: true,
+    complete: false,
+    countedAt: 1
+  }
+})
+
+const paused = status({
+  ...running,
+  progress: { ...running.progress, state: 'paused', cancellable: false, paused: true }
+})
+
+const api = {
+  getImageTextIndexStatus: vi.fn(),
+  countImageMessages: vi.fn(),
+  startImageTextIndex: vi.fn(),
+  pauseImageTextIndex: vi.fn(),
+  resumeImageTextIndex: vi.fn(),
+  cancelImageTextIndex: vi.fn(),
+  resetImageTextIndexFailures: vi.fn(),
+  repairImageTextIndex: vi.fn(),
+  onImageTextIndexStatus: vi.fn(() => () => undefined)
+}
+
+let pushStatus: ((next: ImageTextIndexStatus) => void) | undefined
+
+beforeEach(() => {
+  vi.clearAllMocks()
+  pushStatus = undefined
+  api.getImageTextIndexStatus.mockResolvedValue(notBuilt)
+  api.countImageMessages.mockResolvedValue({
+    totalImageMessages: 12_483,
+    scannedConversations: 42,
+    durationMs: 30
+  })
+  api.startImageTextIndex.mockResolvedValue({ started: true, state: 'running' })
+  api.pauseImageTextIndex.mockResolvedValue({ paused: true, state: 'paused' })
+  api.resumeImageTextIndex.mockResolvedValue({ started: true, state: 'running' })
+  api.cancelImageTextIndex.mockResolvedValue({ cancellable: true, cancelled: true })
+  api.onImageTextIndexStatus.mockImplementation((callback: (next: ImageTextIndexStatus) => void) => {
+    pushStatus = callback
+    return () => undefined
+  })
+  Object.defineProperty(window, 'api', { configurable: true, value: api })
+})
+
+async function renderCard(): Promise<{ onNotice: ReturnType<typeof vi.fn> }> {
+  const onNotice = vi.fn()
+  await act(async () => {
+    render(<ImageTextIndexCard dbReady onNotice={onNotice} />)
+  })
+  return { onNotice }
+}
+
+describe('图片文字索引卡片', () => {
+  it('未建立时给出检测到的图片消息数量，而不是一个空洞的按钮', async () => {
+    await renderCard()
+    expect(screen.getByTestId('image-text-index-state').textContent).toBe('未建立')
+    expect(screen.getByTestId('image-text-index-count').textContent).toBe('12,483')
+    expect(screen.getByTestId('image-text-index-start').textContent).toBe('建立图片文字索引')
+  })
+
+  it('点击建立先弹确认，并把范围、隐私与不可控因素写清楚，确认前不启动', async () => {
+    await renderCard()
+    await userEvent.click(screen.getByTestId('image-text-index-start'))
+
+    // Radix 的 AlertDialog 用的是 role="alertdialog"（不是 "dialog"）。
+    const dialog = await screen.findByRole('alertdialog')
+    expect(dialog.textContent).toContain('12,483')
+    expect(dialog.textContent).toContain('仅在本机进行识别')
+    expect(dialog.textContent).toContain('不会因为本地识别而自动上传')
+    expect(dialog.textContent).toContain('可以暂停并稍后继续')
+    expect(dialog.textContent).toContain('取决于本地图片文件是否仍然存在')
+    // 确认之前绝不允许开跑。
+    expect(api.startImageTextIndex).not.toHaveBeenCalled()
+
+    await userEvent.click(screen.getByTestId('image-text-index-confirm'))
+    await vi.waitFor(() => expect(api.startImageTextIndex).toHaveBeenCalledTimes(1))
+  })
+
+  it('索引进度只给真实数字，并提供暂停与取消', async () => {
+    api.getImageTextIndexStatus.mockResolvedValue(running)
+    await renderCard()
+
+    expect(screen.getByTestId('image-text-index-state').textContent).toBe('建立中 · 30.8%')
+    expect(screen.getByTestId('image-text-index-progress').textContent).toBe('3,842 / 12,483')
+    const passLine = screen.getByText(/识别出文字 2,917/)
+    expect(passLine.textContent).toContain('识别出文字 2,917')
+    expect(passLine.textContent).toContain('没有文字 412')
+    expect(passLine.textContent).toContain('图片已清理 378')
+    expect(passLine.textContent).toContain('失败 135')
+    // 底层实现细节绝不外泄。
+    expect(document.body.textContent).not.toMatch(/HRESULT|0x[0-9A-Fa-f]{8}/)
+
+    await userEvent.click(screen.getByTestId('image-text-index-pause'))
+    expect(api.pauseImageTextIndex).toHaveBeenCalledTimes(1)
+
+    await userEvent.click(screen.getByTestId('image-text-index-cancel'))
+    expect(api.cancelImageTextIndex).toHaveBeenCalledTimes(1)
+  })
+
+  it('暂停后可以继续，进度仍来自主进程快照', async () => {
+    api.getImageTextIndexStatus.mockResolvedValue(paused)
+    await renderCard()
+
+    expect(screen.getByTestId('image-text-index-state').textContent).toBe('已暂停 · 30.8%')
+    await userEvent.click(screen.getByTestId('image-text-index-resume'))
+    expect(api.resumeImageTextIndex).toHaveBeenCalledTimes(1)
+  })
+
+  it('主进程推送真实进度后，卡片跟着更新（重启后恢复的进度同一条路径）', async () => {
+    await renderCard()
+    expect(screen.getByTestId('image-text-index-state').textContent).toBe('未建立')
+
+    await act(async () => {
+      pushStatus?.(running)
+    })
+    expect(screen.getByTestId('image-text-index-state').textContent).toBe('建立中 · 30.8%')
+    expect(screen.getByTestId('image-text-index-progress').textContent).toBe('3,842 / 12,483')
+  })
+
+  it('统计失败时显示「无法统计」而不是 0，并给出原因与重新统计入口', async () => {
+    api.countImageMessages.mockResolvedValue({
+      totalImageMessages: 0,
+      scannedConversations: 0,
+      failedConversations: 7,
+      typeColumn: null,
+      error: '读取消息分片失败',
+      durationMs: 5
+    })
+    await renderCard()
+
+    const value = screen.getByTestId('image-text-index-count')
+    expect(value.textContent).toBe('无法统计')
+    // 这是最关键的一条：绝不能把"数不出来"显示成 0。
+    expect(value.textContent).not.toBe('0')
+
+    const error = screen.getByTestId('image-text-index-count-error')
+    expect(error.textContent).toContain('读取消息分片失败')
+    expect(error.textContent).toContain('不代表账号里没有图片')
+    expect(screen.getByTestId('image-text-index-recount')).toBeVisible()
+  })
+
+  it('部分会话统计失败时给出真实数字并提示偏小', async () => {
+    api.countImageMessages.mockResolvedValue({
+      totalImageMessages: 420,
+      scannedConversations: 30,
+      failedConversations: 2,
+      typeColumn: 'local_type',
+      durationMs: 9
+    })
+    await renderCard()
+
+    expect(screen.getByTestId('image-text-index-count').textContent).toBe('420')
+    expect(screen.getByTestId('image-text-index-count-error').textContent).toContain(
+      '2 个会话未能统计'
+    )
+  })
+
+  it('真的没有图片时才显示 0，且不出现失败提示', async () => {
+    api.countImageMessages.mockResolvedValue({
+      totalImageMessages: 0,
+      scannedConversations: 12,
+      failedConversations: 0,
+      typeColumn: 'local_type',
+      durationMs: 4
+    })
+    await renderCard()
+
+    expect(screen.getByTestId('image-text-index-count').textContent).toBe('0')
+    expect(screen.queryByTestId('image-text-index-count-error')).not.toBeInTheDocument()
+    expect(screen.queryByTestId('image-text-index-recount')).not.toBeInTheDocument()
+  })
+})
+
+/**
+ * 派生索引修复按钮的存在意义就是"别为修一个索引问题重跑几万张图"。
+ *
+ * 因此这里断言的重点是**措辞**：用户看到"修复"两个字必须能确信
+ * 不会又要等一小时 —— 否则这个按钮没人敢点，功能等于不存在。
+ */
+describe('图片文字索引卡片 — 修复图片搜索索引', () => {
+  const established = status({
+    progress: {
+      state: 'idle',
+      totalImageMessages: 45_740,
+      processed: 45_508,
+      indexed: 14_342,
+      empty: 31_126,
+      missing: 38,
+      failed: 2,
+      pending: 232,
+      percent: 99.5,
+      updatedAt: 1,
+      cancellable: false,
+      paused: false
+    },
+    coverage: {
+      totalImageMessages: 45_740,
+      processed: 45_508,
+      indexed: 14_342,
+      empty: 31_126,
+      missing: 38,
+      failed: 2,
+      pending: 232,
+      established: true,
+      complete: false,
+      countedAt: 1,
+      runtimeUnavailable: 0,
+      systemicFailure: false
+    }
+  } as Partial<ImageTextIndexStatus>)
+
+  it('已建立且空闲时提供修复入口，只在点击后调用主进程', async () => {
+    api.getImageTextIndexStatus.mockResolvedValue(established)
+    api.repairImageTextIndex.mockResolvedValue({
+      conversations: 12,
+      ocrExecutions: 0,
+      durationMs: 800,
+      skipped: false
+    })
+    const { onNotice } = await renderCard()
+
+    const button = screen.getByTestId('image-text-index-repair')
+    expect(button.textContent).toBe('修复图片搜索索引')
+    expect(api.repairImageTextIndex).not.toHaveBeenCalled()
+
+    await userEvent.click(button)
+
+    expect(api.repairImageTextIndex).toHaveBeenCalledTimes(1)
+    // 提示语必须讲清楚"没有重新识别"，否则用户会以为又要跑几万张图。
+    expect(String(onNotice.mock.calls.at(-1)?.[0])).toContain('没有重新识别任何图片')
+    expect(String(onNotice.mock.calls.at(-1)?.[0])).toContain('12')
+  })
+
+  it('索引正在跑时不提供修复入口（并发重建会读到半程状态）', async () => {
+    api.getImageTextIndexStatus.mockResolvedValue(running)
+    await renderCard()
+
+    expect(screen.queryByTestId('image-text-index-repair')).not.toBeInTheDocument()
+  })
+
+  it('主进程拒绝并发修复时如实告知，不谎称已修复', async () => {
+    api.getImageTextIndexStatus.mockResolvedValue(established)
+    api.repairImageTextIndex.mockResolvedValue({
+      conversations: 0,
+      ocrExecutions: 0,
+      durationMs: 0,
+      skipped: true
+    })
+    const { onNotice } = await renderCard()
+
+    await userEvent.click(screen.getByTestId('image-text-index-repair'))
+
+    expect(String(onNotice.mock.calls.at(-1)?.[0])).toContain('正在进行中')
+  })
+})
diff --git a/tests/component/support/image-text-index-api.ts b/tests/component/support/image-text-index-api.ts
new file mode 100644
index 0000000..d210cf5
--- /dev/null
+++ b/tests/component/support/image-text-index-api.ts
@@ -0,0 +1,70 @@
+import { vi } from 'vitest'
+import type { ImageTextIndexStatus } from '../../../src/shared/image-text-index'
+
+/**
+ * 默认的「未建立」快照。
+ *
+ * 与主进程 `getStatus()` 在派生库不存在时返回的形状逐字段一致 ——
+ * 测试 fake 要是自己编一个形状，就测不出真实的字段缺失。
+ */
+export function notBuiltImageTextIndexStatus(): ImageTextIndexStatus {
+  return {
+    progress: {
+      state: 'idle',
+      totalImageMessages: 0,
+      processed: 0,
+      indexed: 0,
+      empty: 0,
+      missing: 0,
+      failed: 0,
+      pending: 0,
+      percent: 0,
+      updatedAt: 0,
+      cancellable: false,
+      paused: false
+    },
+    coverage: {
+      totalImageMessages: 0,
+      processed: 0,
+      indexed: 0,
+      empty: 0,
+      missing: 0,
+      failed: 0,
+      pending: 0,
+      established: false,
+      complete: false,
+      countedAt: null
+    },
+    storage: { indexedImages: 0, ocrTextCount: 0, totalBytes: 0, updatedAt: null },
+    counting: false
+  }
+}
+
+/**
+ * Ask-WeChat 相关工作区测试用的「图片文字索引」桥接 fake。
+ *
+ * 真实 preload 一定暴露这些方法；测试里的 `window.api` 是手写对象字面量，
+ * 漏掉任何一个都会让卡片在挂载期抛错，并连带**整个工作区**渲染失败
+ * （一个次要侧栏卡片不该有能力搞挂主界面）。
+ */
+export function makeImageTextIndexApi(overrides: Record<string, unknown> = {}): Record<string, unknown> {
+  return {
+    getImageTextIndexStatus: vi.fn().mockResolvedValue(notBuiltImageTextIndexStatus()),
+    countImageMessages: vi.fn().mockResolvedValue({
+      totalImageMessages: 0,
+      scannedConversations: 0,
+      durationMs: 0
+    }),
+    startImageTextIndex: vi.fn().mockResolvedValue({ started: true, state: 'running' }),
+    pauseImageTextIndex: vi.fn().mockResolvedValue({ paused: true, state: 'paused' }),
+    resumeImageTextIndex: vi.fn().mockResolvedValue({ started: true, state: 'running' }),
+    cancelImageTextIndex: vi.fn().mockResolvedValue({ cancellable: true, cancelled: true }),
+    clearImageTextIndex: vi.fn().mockResolvedValue({ removed: true, removedBytes: 0 }),
+    resetImageTextIndexFailures: vi.fn().mockResolvedValue({ reset: 0 }),
+    repairImageTextIndex: vi
+      .fn()
+      .mockResolvedValue({ conversations: 0, ocrExecutions: 0, durationMs: 0, skipped: false }),
+    onImageTextIndexStatus: vi.fn(() => () => undefined),
+    ...overrides
+  }
+}
diff --git a/tests/integration/image-text-index-incident.test.ts b/tests/integration/image-text-index-incident.test.ts
new file mode 100644
index 0000000..1b6a2a3
--- /dev/null
+++ b/tests/integration/image-text-index-incident.test.ts
@@ -0,0 +1,283 @@
+/**
+ * 事故回归：**"4.5 万张全部失败，UI 却说已建立"** 这一整套语义。
+ *
+ * 真机现场（派生库实测）：
+ *   total = 45,707 / 全部 binding = decrypt_failed 45,479 / artifacts = 0 行
+ * 根因是解密服务在回填时不存在（只在 db:getImage 里懒加载），每张图都在
+ * `processOne` 第一步就失败。这里把"不许再发生"的四件事钉死：
+ *   1. 前置依赖缺失时必须**一条记录都不写**（preflight）；
+ *   2. 处理过但一条没成功 = **异常**，不是"已建立"；
+ *   3. 百分比不许四舍五入到 100（45,479 / 45,707）；
+ *   4. 重置失败记录**不能**动已经成功的记录。
+ */
+import { mkdtempSync } from 'node:fs'
+import { rm } from 'node:fs/promises'
+import { tmpdir } from 'node:os'
+import { join } from 'node:path'
+import { afterEach, describe, expect, it, vi } from 'vitest'
+import type * as chat from '../../src/main/services/chat-service'
+import { ImageTextIndexService } from '../../src/main/services/image-text-index-service'
+import {
+  ImageTextIndexStore,
+  getImageTextIndexDatabasePath
+} from '../../src/main/services/image-text-index-store'
+import {
+  describeImageTextCoverage,
+  imageTextCoverageState,
+  imageTextProcessedPercent,
+  type ImageTextIndexCoverage
+} from '../../src/shared/image-text-index'
+
+const ACCOUNT = 'wxid_incident_fixture'
+const CONVERSATION = 'md5-incident'
+const roots: string[] = []
+
+function makeRoot(): string {
+  const root = mkdtempSync(join(tmpdir(), 'tm-image-incident-'))
+  roots.push(root)
+  return root
+}
+
+afterEach(async () => {
+  await Promise.all(roots.splice(0).map((root) => rm(root, { recursive: true, force: true })))
+})
+
+function imageMessage(localId: number): chat.FormattedMessage {
+  return {
+    localId: String(localId),
+    createTime: 1_700_000_000 + localId,
+    content: '[图片]',
+    contentData: { type: 'image', md5: `md5-${localId}`, datName: `dat-${localId}` }
+  } as unknown as chat.FormattedMessage
+}
+
+function coverageOf(overrides: Partial<ImageTextIndexCoverage>): ImageTextIndexCoverage {
+  return {
+    totalImageMessages: 0,
+    processed: 0,
+    indexed: 0,
+    empty: 0,
+    missing: 0,
+    failed: 0,
+    runtimeUnavailable: 0,
+    pending: 0,
+    established: false,
+    complete: false,
+    systemicFailure: false,
+    countedAt: null,
+    ...overrides
+  }
+}
+
+describe('事故语义：全失败不能叫"已建立"', () => {
+  it('indexed/empty/missing 全为 0 而 failed 不为 0 → 异常，且 complete 必为 false', () => {
+    const coverage = coverageOf({
+      totalImageMessages: 45_707,
+      processed: 45_479,
+      failed: 45_479,
+      pending: 228,
+      established: true,
+      countedAt: 1_789_516_520_246,
+      complete: false, // 服务侧已经算出 false；这里验证状态与文案
+      systemicFailure: true
+    })
+
+    expect(imageTextCoverageState(coverage)).toBe('failed')
+    expect(describeImageTextCoverage(coverage)).toContain('当前异常')
+    expect(describeImageTextCoverage(coverage)).not.toContain('已覆盖全部')
+  })
+
+  it('45,479 / 45,707 不能显示成 100%', () => {
+    // Math.round(45479 / 45707 * 100) === 100 —— 这正是"仅完成 100%"的来源。
+    expect(Math.round((45_479 / 45_707) * 100)).toBe(100)
+    // 正确口径：保留 1 位小数，未完成时封顶 99.9。
+    expect(imageTextProcessedPercent(45_479, 45_707)).toBe(99.5)
+    expect(imageTextProcessedPercent(45_707, 45_707)).toBe(100)
+    expect(imageTextProcessedPercent(0, 0)).toBe(0)
+  })
+
+  it('服务侧：一条都没成功时不给 complete，并把状态判成 failed', async () => {
+    const databaseRoot = makeRoot()
+    const databasePath = getImageTextIndexDatabasePath(databaseRoot, ACCOUNT)
+    const store = new ImageTextIndexStore(databasePath, ACCOUNT)
+    store.writeCountedTotal({ total: 100, countedAt: 1, complete: true })
+    for (let index = 1; index <= 30; index += 1) {
+      store.putBinding({
+        accountId: ACCOUNT,
+        conversationId: CONVERSATION,
+        messageId: `local:${index}`,
+        createTime: index,
+        imageIdentity: '',
+        artifactKey: `unavailable|${index}`,
+        state: 'decrypt_failed',
+        updatedAt: index
+      })
+    }
+    store.close()
+
+    const service = new ImageTextIndexService()
+    service.bind({ databaseRoot, resolveAccountId: () => ACCOUNT })
+    const status = await service.getStatus()
+
+    expect(status.coverage.processed).toBe(30)
+    expect(status.coverage.failed).toBe(30)
+    expect(status.coverage.systemicFailure).toBe(true)
+    expect(status.coverage.complete).toBe(false)
+    expect(imageTextCoverageState(status.coverage)).toBe('failed')
+    // 收干净句柄：Windows 上没关连接会让临时目录清理 EBUSY。
+    service.resetAccount()
+  })
+
+  it('运行时不可用不计入 processed，并且阻断 complete', async () => {
+    const databaseRoot = makeRoot()
+    const databasePath = getImageTextIndexDatabasePath(databaseRoot, ACCOUNT)
+    const store = new ImageTextIndexStore(databasePath, ACCOUNT)
+    store.writeCountedTotal({ total: 10, countedAt: 1, complete: true })
+    store.putBinding({
+      accountId: ACCOUNT,
+      conversationId: CONVERSATION,
+      messageId: 'local:1',
+      createTime: 1,
+      imageIdentity: '',
+      artifactKey: 'unavailable|1',
+      state: 'decrypt_unavailable',
+      updatedAt: 1
+    })
+    store.close()
+
+    const service = new ImageTextIndexService()
+    service.bind({ databaseRoot, resolveAccountId: () => ACCOUNT })
+    const status = await service.getStatus()
+
+    expect(status.coverage.runtimeUnavailable).toBe(1)
+    expect(status.coverage.processed).toBe(0)
+    expect(status.coverage.complete).toBe(false)
+    service.resetAccount()
+  })
+
+  it('部分成功 + 部分图片缺失 → 仍然是正常的"部分完成"（不误判成异常）', () => {
+    const coverage = coverageOf({
+      totalImageMessages: 100,
+      processed: 100,
+      indexed: 60,
+      empty: 20,
+      missing: 20,
+      established: true,
+      countedAt: 1,
+      complete: true,
+      systemicFailure: false
+    })
+    expect(imageTextCoverageState(coverage)).toBe('complete')
+    expect(describeImageTextCoverage(coverage)).toContain('已覆盖全部')
+  })
+})
+
+describe('事故防线：前置依赖缺失时一条记录都不写', () => {
+  it('解密服务不可用 → pass 直接报错，不写任何 binding', async () => {
+    const databaseRoot = makeRoot()
+    const databasePath = getImageTextIndexDatabasePath(databaseRoot, ACCOUNT)
+    const service = new ImageTextIndexService()
+    service.bind({
+      databaseRoot,
+      resolveAccountId: () => ACCOUNT,
+      listContacts: async () => [
+        { md5: CONVERSATION, m_nsUsrName: 'incident', type: 'group' as const }
+      ],
+      listMessages: async () => [imageMessage(1)],
+      countConversationImages: async () => ({ count: 1, typeColumn: 'local_type' }),
+      imageWatermark: async () => ({ count: 1, maxLocalId: 1 }),
+      capability: async () => ({
+        available: true,
+        engine: 'windows-system-ocr',
+        platform: 'win32',
+        runtimeVersion: '1.2.0',
+        language: 'zh-Hans-CN'
+      }),
+      // 关键：没有解密服务（本次事故的根因形态）
+      decryptService: () => null
+    })
+
+    await service.startPass()
+    await vi.waitFor(() => expect(service.isRunning()).toBe(false))
+
+    const status = await service.getStatus()
+    // 这一条就是整场事故的防线：宁可一次都不跑，也不要写 45,479 条假失败。
+    expect(status.progress.state).toBe('error')
+    expect(status.progress.lastError).toContain('解密服务')
+    expect(status.coverage.processed).toBe(0)
+    expect(status.coverage.failed).toBe(0)
+    expect(status.coverage.runtimeUnavailable).toBe(0)
+
+    const store = new ImageTextIndexStore(databasePath, ACCOUNT)
+    expect(store.countByState()).toEqual({})
+    store.close()
+    service.resetAccount()
+  })
+})
+
+describe('事故收尾：重置失败记录不能动成功记录', () => {
+  it('只删失败绑定与它们的 checkpoint，indexed 一条不动', async () => {
+    const databaseRoot = makeRoot()
+    const databasePath = getImageTextIndexDatabasePath(databaseRoot, ACCOUNT)
+    const store = new ImageTextIndexStore(databasePath, ACCOUNT)
+    store.writeCountedTotal({ total: 3, countedAt: 1, complete: true })
+    store.putArtifact({
+      accountId: ACCOUNT,
+      artifactKey: 'good|1',
+      imageIdentity: 'sha256:good',
+      state: 'indexed',
+      text: 'TRACE_KEEP_ME',
+      charCount: 13,
+      engine: 'windows-system-ocr',
+      platform: 'win32',
+      runtimeVersion: '1.2.0',
+      language: 'zh-Hans-CN',
+      createdAt: 1,
+      updatedAt: 1
+    })
+    store.putBinding({
+      accountId: ACCOUNT,
+      conversationId: CONVERSATION,
+      messageId: 'local:1',
+      createTime: 1,
+      imageIdentity: 'sha256:good',
+      artifactKey: 'good|1',
+      state: 'indexed',
+      updatedAt: 1
+    })
+    for (const id of [2, 3]) {
+      store.putBinding({
+        accountId: ACCOUNT,
+        conversationId: CONVERSATION,
+        messageId: `local:${id}`,
+        createTime: id,
+        imageIdentity: '',
+        artifactKey: `bad|${id}`,
+        state: 'decrypt_failed',
+        updatedAt: id
+      })
+    }
+    store.writeScanState({
+      conversationId: CONVERSATION,
+      state: 'done',
+      imageTotal: 3,
+      imageProcessed: 3,
+      maxLocalId: 3
+    })
+    store.close()
+
+    const service = new ImageTextIndexService()
+    service.bind({ databaseRoot, resolveAccountId: () => ACCOUNT })
+    const result = await service.resetRetriableFailures()
+    expect(result.reset).toBe(2)
+
+    // 成功记录与它的 artifact 必须原封不动。
+    const after = new ImageTextIndexStore(databasePath, ACCOUNT)
+    expect(after.countByState()).toEqual({ indexed: 1 })
+    expect(after.getArtifact('good|1')?.text).toBe('TRACE_KEEP_ME')
+    // checkpoint 也要清掉，否则下一轮会以"该会话已完成"直接跳过（点了重试却没反应）。
+    expect(after.readScanState().size).toBe(0)
+    after.close()
+    service.resetAccount()
+  })
+})
diff --git a/tests/integration/image-text-index-incremental-repair.test.ts b/tests/integration/image-text-index-incremental-repair.test.ts
new file mode 100644
index 0000000..968d42c
--- /dev/null
+++ b/tests/integration/image-text-index-incremental-repair.test.ts
@@ -0,0 +1,312 @@
+/**
+ * 两条**成本**契约（都在真机上被踩过）：
+ *
+ * 1. 「更新图片文字索引」必须是增量的。
+ *    真机已经跑了 1 小时、留下 14,342 条 OCR 文本 + 31,126 条 empty 终态。
+ *    OCR 是昂贵产物，Knowledge / FTS / binding 才是可重建派生层 ——
+ *    更新时只能处理 new / pending / retryable，**已有终态一条都不许重算**。
+ *
+ * 2. 修索引问题不许重跑 OCR（Derived Index Repair）。
+ *    只重建 L3（Knowledge 派生条目 / FTS），数据来源是已有 L1/L2；
+ *    `ocrExecutions: 0` 是写进类型字面量的契约，不是"期望值"。
+ */
+import { mkdtempSync } from 'node:fs'
+import { rm } from 'node:fs/promises'
+import { tmpdir } from 'node:os'
+import { join } from 'node:path'
+import { afterEach, describe, expect, it, vi } from 'vitest'
+import type * as chat from '../../src/main/services/chat-service'
+import { ImageTextIndexService } from '../../src/main/services/image-text-index-service'
+import {
+  ImageTextIndexStore,
+  getImageTextIndexDatabasePath
+} from '../../src/main/services/image-text-index-store'
+
+const ACCOUNT = 'wxid_incremental_fixture'
+const CONVERSATION = 'md5-incremental'
+const roots: string[] = []
+
+function makeRoot(): string {
+  const root = mkdtempSync(join(tmpdir(), 'tm-image-incremental-'))
+  roots.push(root)
+  return root
+}
+
+afterEach(async () => {
+  await Promise.all(roots.splice(0).map((root) => rm(root, { recursive: true, force: true })))
+})
+
+/** 合法的 PNG 头（`detectSystemOcrImageFormat` 只认前 4 字节），尾部塞一个唯一序号。 */
+function pngBytes(seed: number): Buffer {
+  return Buffer.from([0x89, 0x50, 0x4e, 0x47, 0x0d, 0x0a, 0x1a, 0x0a, seed & 0xff, (seed >> 8) & 0xff])
+}
+
+function imageMessage(localId: number): chat.FormattedMessage {
+  return {
+    id: String(localId),
+    localId: String(localId),
+    from: 'user',
+    type: '图片',
+    content: '',
+    isSender: false,
+    name: '对方',
+    contentData: { type: 'image', md5: `md5-${localId}`, datName: `dat-${localId}` },
+    createTime: 1_700_000_000 + localId
+  } as unknown as chat.FormattedMessage
+}
+
+/** 假的派生库预热：写入 `count` 条已完成的 OCR 记录（成功终态）。 */
+function seedTerminal(store: ImageTextIndexStore, count: number, state: 'indexed' | 'empty'): void {
+  for (let index = 1; index <= count; index += 1) {
+    const artifactKey = `seeded|${index}`
+    store.putArtifact({
+      accountId: ACCOUNT,
+      artifactKey,
+      imageIdentity: `sha256:seeded-${index}`,
+      state,
+      text: state === 'indexed' ? `TRACE_SEEDED_${index}` : '',
+      charCount: state === 'indexed' ? 16 : 0,
+      engine: 'windows-system-ocr',
+      platform: 'win32',
+      runtimeVersion: '1.2.0',
+      language: 'zh-Hans-CN',
+      createdAt: index,
+      updatedAt: index
+    })
+    store.putBinding({
+      accountId: ACCOUNT,
+      conversationId: CONVERSATION,
+      messageId: `local:${index}`,
+      createTime: index,
+      imageIdentity: `sha256:seeded-${index}`,
+      artifactKey,
+      state,
+      updatedAt: index
+    })
+  }
+}
+
+describe('增量更新：已有终态直接复用，只对新增/未完成做 OCR', () => {
+  it('已有 100 条终态 + 新增 10 张 + 2 条未完成 → OCR 只跑 12 次', async () => {
+    const databaseRoot = makeRoot()
+    const databasePath = getImageTextIndexDatabasePath(databaseRoot, ACCOUNT)
+    const store = new ImageTextIndexStore(databasePath, ACCOUNT)
+    seedTerminal(store, 100, 'indexed')
+    // 2 条"未完成"：binding 状态不是终态 → 允许重试。
+    for (const id of [111, 112]) {
+      store.putBinding({
+        accountId: ACCOUNT,
+        conversationId: CONVERSATION,
+        messageId: `local:${id}`,
+        createTime: id,
+        imageIdentity: '',
+        artifactKey: `pending|${id}`,
+        state: 'pending',
+        updatedAt: id
+      })
+    }
+    // 旧 checkpoint：当时该会话只有 100 张、水位 100。
+    store.writeScanState({
+      conversationId: CONVERSATION,
+      state: 'done',
+      imageTotal: 100,
+      imageProcessed: 100,
+      maxLocalId: 100
+    })
+    store.close()
+
+    // 现在源数据变成 112 张（1..100 已有终态，101..110 全新，111..112 之前没跑完）。
+    const messages = Array.from({ length: 112 }, (_, index) => imageMessage(index + 1))
+    const recognize = vi.fn(async () => ({
+      success: true,
+      text: 'TRACE_FRESH_TEXT',
+      language: 'zh-Hans-CN'
+    }))
+    const decryptImage = vi.fn((path: string) => {
+      const seed = Number(String(path).replace(/\D/g, '')) || 0
+      return pngBytes(seed)
+    })
+
+    const service = new ImageTextIndexService()
+    service.bind({
+      databaseRoot,
+      resolveAccountId: () => ACCOUNT,
+      listContacts: async () => [
+        { md5: CONVERSATION, m_nsUsrName: 'incremental', type: 'user' as const }
+      ],
+      listMessages: async () => messages,
+      countConversationImages: async () => ({ count: 112, typeColumn: 'local_type' }),
+      imageWatermark: async () => ({ count: 112, maxLocalId: 112 }),
+      capability: async () => ({
+        available: true,
+        engine: 'windows-system-ocr',
+        platform: 'win32',
+        runtimeVersion: '1.2.0',
+        language: 'zh-Hans-CN'
+      }),
+      decryptService: () => ({ findImageFile: (md5) => `C:/fake/${md5}.dat`, decryptImage }) as never,
+      recognize
+    })
+
+    await service.startPass()
+    await vi.waitFor(() => expect(service.isRunning()).toBe(false))
+
+    // 关键断言：12 次，而不是 112 次。
+    expect(recognize).toHaveBeenCalledTimes(12)
+    // 已有终态那 100 条连解密都不该碰。
+    expect(decryptImage).toHaveBeenCalledTimes(12)
+
+    const after = new ImageTextIndexStore(databasePath, ACCOUNT)
+    // 100 条旧终态 + 100 个旧 artifact 一条不少，文本原样保留（不重算、不覆盖）。
+    expect(after.countByState().indexed).toBe(112)
+    expect(after.getArtifact('seeded|1')?.text).toBe('TRACE_SEEDED_1')
+    expect(after.getArtifact('seeded|100')?.text).toBe('TRACE_SEEDED_100')
+    after.close()
+    service.resetAccount()
+  })
+
+  it('水位完全没变 → 整个会话直接跳过，OCR 一次都不调', async () => {
+    const databaseRoot = makeRoot()
+    const databasePath = getImageTextIndexDatabasePath(databaseRoot, ACCOUNT)
+    const store = new ImageTextIndexStore(databasePath, ACCOUNT)
+    seedTerminal(store, 20, 'empty')
+    store.writeScanState({
+      conversationId: CONVERSATION,
+      state: 'done',
+      imageTotal: 20,
+      imageProcessed: 20,
+      maxLocalId: 20
+    })
+    store.close()
+
+    const recognize = vi.fn(async () => ({ success: true, text: 'X', language: null }))
+    const service = new ImageTextIndexService()
+    service.bind({
+      databaseRoot,
+      resolveAccountId: () => ACCOUNT,
+      listContacts: async () => [
+        { md5: CONVERSATION, m_nsUsrName: 'incremental', type: 'user' as const }
+      ],
+      listMessages: async () => Array.from({ length: 20 }, (_, index) => imageMessage(index + 1)),
+      countConversationImages: async () => ({ count: 20, typeColumn: 'local_type' }),
+      imageWatermark: async () => ({ count: 20, maxLocalId: 20 }),
+      capability: async () => ({
+        available: true,
+        engine: 'windows-system-ocr',
+        platform: 'win32',
+        runtimeVersion: '1.2.0',
+        language: null
+      }),
+      decryptService: () => ({ findImageFile: () => null, decryptImage: () => null }) as never,
+      recognize
+    })
+
+    await service.startPass()
+    await vi.waitFor(() => expect(service.isRunning()).toBe(false))
+
+    expect(recognize).not.toHaveBeenCalled()
+    service.resetAccount()
+  })
+})
+
+describe('派生索引修复：只重建 L3，绝不重跑 OCR', () => {
+  it('只重建"有 OCR 文本"的会话，且 recognize 一次都不被调用', async () => {
+    const databaseRoot = makeRoot()
+    const databasePath = getImageTextIndexDatabasePath(databaseRoot, ACCOUNT)
+    const store = new ImageTextIndexStore(databasePath, ACCOUNT)
+    seedTerminal(store, 3, 'indexed')
+    // 另一个会话只有 empty（没有派生文本可修）→ 不该被重建，白读一遍 WCDB。
+    store.putArtifact({
+      accountId: ACCOUNT,
+      artifactKey: 'empty-only|1',
+      imageIdentity: 'sha256:empty-only',
+      state: 'empty',
+      text: '',
+      charCount: 0,
+      engine: 'windows-system-ocr',
+      platform: 'win32',
+      runtimeVersion: '1.2.0',
+      language: null,
+      createdAt: 1,
+      updatedAt: 1
+    })
+    store.putBinding({
+      accountId: ACCOUNT,
+      conversationId: 'md5-empty-only',
+      messageId: 'local:1',
+      createTime: 1,
+      imageIdentity: 'sha256:empty-only',
+      artifactKey: 'empty-only|1',
+      state: 'empty',
+      updatedAt: 1
+    })
+    store.close()
+
+    const recognize = vi.fn(async () => ({ success: true, text: 'X', language: null }))
+    const onConversationIndexed = vi.fn(async () => undefined)
+    const service = new ImageTextIndexService()
+    service.bind({
+      databaseRoot,
+      resolveAccountId: () => ACCOUNT,
+      recognize,
+      onConversationIndexed
+    })
+
+    const result = await service.repairKnowledgeIndex()
+
+    expect(result.skipped).toBe(false)
+    expect(result.conversations).toBe(1)
+    // 契约：修复路径的定义就是"不调 OCR"。类型上写死成字面量 0。
+    expect(result.ocrExecutions).toBe(0)
+    expect(recognize).not.toHaveBeenCalled()
+    expect(onConversationIndexed).toHaveBeenCalledTimes(1)
+    expect(onConversationIndexed).toHaveBeenCalledWith(CONVERSATION)
+    service.resetAccount()
+  })
+
+  it('索引任务正在跑时拒绝并发修复（避免读到半程 binding）', async () => {
+    const databaseRoot = makeRoot()
+    const databasePath = getImageTextIndexDatabasePath(databaseRoot, ACCOUNT)
+    const store = new ImageTextIndexStore(databasePath, ACCOUNT)
+    seedTerminal(store, 1, 'indexed')
+    store.close()
+
+    let release: (() => void) | null = null
+    const gate = new Promise<void>((resolve) => {
+      release = resolve
+    })
+
+    const service = new ImageTextIndexService()
+    service.bind({
+      databaseRoot,
+      resolveAccountId: () => ACCOUNT,
+      listContacts: async () => [
+        { md5: CONVERSATION, m_nsUsrName: 'incremental', type: 'user' as const }
+      ],
+      listMessages: async () => [imageMessage(1)],
+      countConversationImages: async () => ({ count: 1, typeColumn: 'local_type' }),
+      imageWatermark: async () => ({ count: 1, maxLocalId: 1 }),
+      capability: async () => ({
+        available: true,
+        engine: 'windows-system-ocr',
+        platform: 'win32',
+        runtimeVersion: '1.2.0',
+        language: null
+      }),
+      decryptService: () => ({ findImageFile: () => null, decryptImage: () => null }) as never,
+      // 卡住 pass，让 running 保持为真。
+      interactiveIdle: () => gate
+    })
+
+    await service.startPass()
+    await vi.waitFor(() => expect(service.isRunning()).toBe(true))
+
+    const during = await service.repairKnowledgeIndex()
+    expect(during.skipped).toBe(true)
+    expect(during.conversations).toBe(0)
+
+    release?.()
+    await vi.waitFor(() => expect(service.isRunning()).toBe(false))
+    service.resetAccount()
+  })
+})
diff --git a/tests/integration/image-text-index-knowledge-invalidation.test.ts b/tests/integration/image-text-index-knowledge-invalidation.test.ts
new file mode 100644
index 0000000..da576a0
--- /dev/null
+++ b/tests/integration/image-text-index-knowledge-invalidation.test.ts
@@ -0,0 +1,283 @@
+/**
+ * §2 / §3 的硬条件：清理图片文字索引必须让 **Knowledge 里已经产生的 OCR 派生文字**一起失效。
+ *
+ * 背景：OCR 文本经 normalizer 的固定前缀 `图片文字：` 拼进 `searchableText`，
+ * 再进 chunks / FTS。所以"清理成功"不能只等于"派生 SQLite 删掉了" ——
+ * 用户执行设置里的「清理图片文字索引」之后，`search_messages` 必须搜不到那些图片文字，
+ * 同时**普通文字消息必须一条不少地留着**。
+ *
+ * 本文件分两部分：
+ * - A：Knowledge 侧的失效机制本身成立（内容变了 / 消息被移除都会被重建替换）；
+ * - B：生产路径真的触发了它（`imageTextIndexService.clear()` 会逐会话重建）。
+ */
+import { mkdtempSync } from 'node:fs'
+import { rm } from 'node:fs/promises'
+import { tmpdir } from 'node:os'
+import { join } from 'node:path'
+import { afterEach, describe, expect, it, vi } from 'vitest'
+import {
+  DEFAULT_KNOWLEDGE_CHUNKER,
+  type KnowledgeFtsConfig,
+  type KnowledgeSourceMessage
+} from '../../src/shared/knowledge'
+import { KnowledgeStore } from '../../src/main/knowledge/knowledge-store'
+import { ImageTextIndexService } from '../../src/main/services/image-text-index-service'
+import { getImageTextIndexDatabasePath } from '../../src/main/services/image-text-index-store'
+import type * as chat from '../../src/main/services/chat-service'
+
+const ACCOUNT = 'fixture-account-image-ocr'
+const CONVERSATION = 'conversation-image-ocr'
+const OCR_TOKEN = 'TRACE_IMAGE_OCR_UNIQUE_2026'
+const PLAIN_TEXT = '普通聊天内容保留'
+const IMAGE_MESSAGE_ID = 'local:9001'
+const TEXT_MESSAGE_ID = 'local:9002'
+
+const fts: KnowledgeFtsConfig = {
+  profileId: 'test-trigram-external-full',
+  tokenizer: 'trigram',
+  contentMode: 'external',
+  detail: 'full',
+  columnsize: 1
+}
+
+const roots: string[] = []
+
+function makeRoot(): string {
+  const root = mkdtempSync(join(tmpdir(), 'wxe-image-ocr-invalidation-'))
+  roots.push(root)
+  return root
+}
+
+afterEach(async () => {
+  await Promise.all(roots.splice(0).map((root) => rm(root, { recursive: true, force: true })))
+})
+
+function textMessage(): KnowledgeSourceMessage {
+  return {
+    accountId: ACCOUNT,
+    conversationId: CONVERSATION,
+    messageId: TEXT_MESSAGE_ID,
+    createTime: Date.UTC(2026, 8, 1, 10, 0),
+    senderId: 'fixture-member-1',
+    senderName: '张三',
+    kind: 'text',
+    text: PLAIN_TEXT
+  }
+}
+
+/** 带 OCR 派生文本的图片消息（这是 OCR 索引建立后的状态）。 */
+function imageMessageWithOcr(caption?: string): KnowledgeSourceMessage {
+  return {
+    accountId: ACCOUNT,
+    conversationId: CONVERSATION,
+    messageId: IMAGE_MESSAGE_ID,
+    createTime: Date.UTC(2026, 8, 1, 10, 5),
+    senderId: 'fixture-member-2',
+    senderName: '李四',
+    kind: 'image',
+    ...(caption ? { text: caption } : {}),
+    imageOcrText: OCR_TOKEN,
+    imageOcrState: 'indexed'
+  }
+}
+
+/** 同一张图片，但 OCR 派生文本已经不存在（= 派生库被清掉后 resolver 拿不到东西）。 */
+function imageMessageWithoutOcr(caption?: string): KnowledgeSourceMessage {
+  return {
+    accountId: ACCOUNT,
+    conversationId: CONVERSATION,
+    messageId: IMAGE_MESSAGE_ID,
+    createTime: Date.UTC(2026, 8, 1, 10, 5),
+    senderId: 'fixture-member-2',
+    senderName: '李四',
+    kind: 'image',
+    ...(caption ? { text: caption } : {})
+  }
+}
+
+function searchTokens(store: KnowledgeStore, text: string): string[] {
+  return store
+    .search({ accountId: ACCOUNT, text, limit: 20 })
+    .map((item) => item.messageId)
+}
+
+function evidenceFor(store: KnowledgeStore, text: string) {
+  return store.search({ accountId: ACCOUNT, text, limit: 20 })
+}
+
+async function indexConversation(
+  store: KnowledgeStore,
+  messages: KnowledgeSourceMessage[]
+): Promise<void> {
+  await store.index({
+    conversations: [{ conversationId: CONVERSATION, completeSnapshot: true, messages }],
+    chunker: DEFAULT_KNOWLEDGE_CHUNKER
+  })
+}
+
+describe('§2-A Knowledge 侧的失效机制：OCR 派生文字必须能真的消失', () => {
+  it('图片消息仍然存在、只是 OCR 文本没了 → 旧 OCR 文字搜不到，普通文字不受影响', async () => {
+    const store = new KnowledgeStore(makeRoot(), ACCOUNT, fts)
+
+    // 1) 建立图片 OCR 派生记录 + 完成索引
+    await indexConversation(store, [textMessage(), imageMessageWithOcr()])
+
+    // 2) 必须能搜到，并且命中的是**原始图片消息**
+    const before = evidenceFor(store, OCR_TOKEN)
+    expect(before.length).toBeGreaterThan(0)
+    expect(before[0].messageId).toBe(IMAGE_MESSAGE_ID)
+    expect(before[0].sourceKind).toBe('image')
+
+    // 3) OCR 文本被清掉（模拟「清理图片文字索引」后重建）
+    await indexConversation(store, [textMessage(), imageMessageWithoutOcr()])
+
+    // 4) 旧 OCR 文字必须彻底搜不到
+    expect(searchTokens(store, OCR_TOKEN)).toEqual([])
+
+    // 5) 普通文字消息必须仍然命中 —— 不能清掉普通 Knowledge
+    expect(searchTokens(store, PLAIN_TEXT)).toContain(TEXT_MESSAGE_ID)
+
+    store.close()
+  })
+
+  it('无文字图片消息在 OCR 清掉后被整体移除 → 旧 OCR 文字同样搜不到', async () => {
+    const store = new KnowledgeStore(makeRoot(), ACCOUNT, fts)
+
+    // 这条图片消息除了 OCR 文本之外没有任何内容；OCR 一清，它就不该再进索引。
+    await indexConversation(store, [textMessage(), imageMessageWithOcr()])
+    expect(searchTokens(store, OCR_TOKEN).length).toBeGreaterThan(0)
+
+    await indexConversation(store, [textMessage()])
+
+    expect(searchTokens(store, OCR_TOKEN)).toEqual([])
+    expect(searchTokens(store, PLAIN_TEXT)).toContain(TEXT_MESSAGE_ID)
+
+    store.close()
+  })
+
+  it('§3：OCR 文本变化（state 仍是 indexed）也必须让旧文本失效', async () => {
+    const store = new KnowledgeStore(makeRoot(), ACCOUNT, fts)
+
+    await indexConversation(store, [textMessage(), imageMessageWithOcr()])
+    expect(searchTokens(store, OCR_TOKEN).length).toBeGreaterThan(0)
+
+    // 同一个 state（indexed），内容换成了另一段文字 —— 例如换了 OCR 运行时后重新识别。
+    const replaced = {
+      ...imageMessageWithOcr(),
+      imageOcrText: 'TRACE_IMAGE_OCR_REPLACED_2026'
+    }
+    await indexConversation(store, [textMessage(), replaced])
+
+    expect(searchTokens(store, OCR_TOKEN)).toEqual([])
+    expect(searchTokens(store, 'TRACE_IMAGE_OCR_REPLACED_2026')).toContain(IMAGE_MESSAGE_ID)
+
+    store.close()
+  })
+})
+
+describe('§2-B 生产路径：清理必须逐会话重建 Knowledge', () => {
+  function imageMessage(localId: number, conversationId: string): chat.FormattedMessage {
+    return {
+      localId: String(localId),
+      createTime: 1_700_000_000 + localId,
+      content: '[图片]',
+      contentData: { type: 'image', md5: `md5-${localId}`, datName: `dat-${localId}` },
+      sessionId: conversationId
+    } as unknown as chat.FormattedMessage
+  }
+
+  it('clear() 对每个有 OCR 派生文本的会话都触发一次重建，而不是清空整个 Knowledge', async () => {
+    const databaseRoot = makeRoot()
+    const conversations = ['conv-alpha', 'conv-beta']
+    const onConversationIndexed = vi.fn(async () => undefined)
+
+    const service = new ImageTextIndexService()
+    service.bind({
+      databaseRoot,
+      resolveAccountId: () => ACCOUNT,
+      listContacts: async () =>
+        conversations.map((md5) => ({ md5, m_nsUsrName: md5, type: 'group' as const })),
+      listMessages: async (conversationId) => [imageMessage(1, conversationId)],
+      countConversationImages: async () => ({ count: 1, typeColumn: 'local_type' }),
+      imageWatermark: async () => ({ count: 1, maxLocalId: 1 }),
+      // 没有解密服务 → 图片判为 image_missing；这不影响"这条会话有没有 OCR 绑定"。
+      decryptService: () => ({ findImageFile: () => null, decryptImage: () => null }) as never,
+      capability: async () => ({
+        available: true,
+        engine: 'windows-system-ocr',
+        platform: 'win32',
+        runtimeVersion: '1.2.0',
+        language: 'zh-Hans-CN'
+      }),
+      onConversationIndexed
+    })
+
+    await service.startPass()
+    await vi.waitFor(() => expect(service.isRunning()).toBe(false))
+
+    // 两个会话都真的产生了绑定。
+    const databasePath = getImageTextIndexDatabasePath(databaseRoot, ACCOUNT)
+    expect(onConversationIndexed).toHaveBeenCalledTimes(2)
+
+    onConversationIndexed.mockClear()
+    const result = await service.clear()
+
+    expect(result.removed).toBe(true)
+    // 关键：清理必须重建这两个会话，否则 Knowledge 里还留着图片文字。
+    expect(onConversationIndexed).toHaveBeenCalledTimes(2)
+    expect(onConversationIndexed.mock.calls.map((call) => call[0]).sort()).toEqual(
+      [...conversations].sort()
+    )
+    expect(service.lastInvalidatedConversations).toBe(2)
+    expect(databasePath).toBeTruthy()
+  })
+
+  it('prepareForCacheClear() 同样会做失效（"清理全部"路径不能漏）', async () => {
+    const databaseRoot = makeRoot()
+    const onConversationIndexed = vi.fn(async () => undefined)
+
+    const service = new ImageTextIndexService()
+    service.bind({
+      databaseRoot,
+      resolveAccountId: () => ACCOUNT,
+      listContacts: async () => [
+        { md5: CONVERSATION, m_nsUsrName: CONVERSATION, type: 'group' as const }
+      ],
+      listMessages: async () => [imageMessage(1, CONVERSATION)],
+      countConversationImages: async () => ({ count: 1, typeColumn: 'local_type' }),
+      imageWatermark: async () => ({ count: 1, maxLocalId: 1 }),
+      decryptService: () => ({ findImageFile: () => null, decryptImage: () => null }) as never,
+      capability: async () => ({
+        available: true,
+        engine: 'windows-system-ocr',
+        platform: 'win32',
+        runtimeVersion: '1.2.0',
+        language: 'zh-Hans-CN'
+      }),
+      onConversationIndexed
+    })
+
+    await service.startPass()
+    await vi.waitFor(() => expect(service.isRunning()).toBe(false))
+    onConversationIndexed.mockClear()
+
+    await service.prepareForCacheClear()
+
+    expect(onConversationIndexed).toHaveBeenCalledWith(CONVERSATION)
+  })
+
+  it('派生库里没有 OCR 绑定时，清理不触发任何无意义的重建', async () => {
+    const databaseRoot = makeRoot()
+    const onConversationIndexed = vi.fn(async () => undefined)
+    const service = new ImageTextIndexService()
+    service.bind({
+      databaseRoot,
+      resolveAccountId: () => ACCOUNT,
+      onConversationIndexed
+    })
+
+    const result = await service.clear()
+    expect(result.removed).toBe(true)
+    expect(onConversationIndexed).not.toHaveBeenCalled()
+  })
+})
diff --git a/tests/integration/image-text-index-p0.test.ts b/tests/integration/image-text-index-p0.test.ts
new file mode 100644
index 0000000..6f15fe4
--- /dev/null
+++ b/tests/integration/image-text-index-p0.test.ts
@@ -0,0 +1,409 @@
+/**
+ * 「图片文字索引」的 P0 语义测试。
+ *
+ * 这里覆盖的都是**不能用 UI 数字糊过去**的硬约束：
+ * - 覆盖度必须在重启后依然诚实（派生库只知道处理过什么，不知道源数据一共多少）；
+ * - 增量判据必须能发现「总数没变但集合变了」；
+ * - 清理必须真的把文件删掉，删不掉要如实上报；
+ * - 涉及图片的问题在索引未完成时，答案语义里必须带"不能因为没搜到就说没有"。
+ */
+import { existsSync, mkdtempSync, rmSync } from 'node:fs'
+import { tmpdir } from 'node:os'
+import { join } from 'node:path'
+import { afterEach, describe, expect, it, vi } from 'vitest'
+import type * as chat from '../../src/main/services/chat-service'
+import { ImageTextIndexService } from '../../src/main/services/image-text-index-service'
+import {
+  ImageTextIndexStore,
+  getImageTextIndexDatabasePath
+} from '../../src/main/services/image-text-index-store'
+import { buildImageOcrCoverage } from '../../src/main/services/local-query-api-service'
+import type { ImageTextIndexCoverage } from '../../src/shared/image-text-index'
+
+const ACCOUNT = 'wxid_fixture_account'
+const CONVERSATION = 'conversation-md5-fixture'
+const roots: string[] = []
+
+function makeDatabaseRoot(): string {
+  const root = mkdtempSync(join(tmpdir(), 'tm-image-text-index-'))
+  roots.push(root)
+  return root
+}
+
+afterEach(() => {
+  for (const root of roots.splice(0)) {
+    try {
+      rmSync(root, { recursive: true, force: true })
+    } catch {
+      // 测试收尾尽力而为。
+    }
+  }
+})
+
+/** 只带图片索引需要的字段；其余字段与本测试无关。 */
+function imageMessage(localId: number, createTime: number): chat.FormattedMessage {
+  return {
+    localId: String(localId),
+    createTime,
+    content: '[图片]',
+    contentData: { type: 'image', md5: `md5-${localId}`, datName: `dat-${localId}` }
+  } as unknown as chat.FormattedMessage
+}
+
+type Harness = {
+  service: ImageTextIndexService
+  databaseRoot: string
+  listMessages: ReturnType<typeof vi.fn>
+  watermark: { count: number; maxLocalId: number }
+  databasePath: string
+}
+
+function makeHarness(options: { messages?: chat.FormattedMessage[] } = {}): Harness {
+  const databaseRoot = makeDatabaseRoot()
+  const listMessages = vi.fn(async () => options.messages ?? [])
+  const watermark = { count: 0, maxLocalId: 0 }
+  const service = new ImageTextIndexService()
+  service.bind({
+    databaseRoot,
+    resolveAccountId: () => ACCOUNT,
+    resolveAccountRoot: () => 'C:/fixture/account',
+    listContacts: async () => [
+      { md5: CONVERSATION, m_nsUsrName: 'fixture', type: 'group' as const }
+    ],
+    listMessages,
+    countConversationImages: async () => ({ count: watermark.count, typeColumn: 'local_type' }),
+    imageWatermark: async () => ({ ...watermark }),
+    // 没有解密服务 → 每张图片都会被判成 image_missing。这样测试完全不碰真实图片。
+    decryptService: () => ({ findImageFile: () => null, decryptImage: () => null }) as never,
+    capability: async () => ({
+      available: true,
+      engine: 'windows-system-ocr',
+      platform: 'win32',
+      runtimeVersion: '1.2.0',
+      language: 'zh-Hans-CN'
+    }),
+    recognize: async () => ({ success: true, text: '', language: 'zh-Hans-CN' })
+  })
+  return {
+    service,
+    databaseRoot,
+    listMessages,
+    watermark,
+    databasePath: getImageTextIndexDatabasePath(databaseRoot, ACCOUNT)
+  }
+}
+
+describe('§2 增量水位：只比条数会漏掉「等量替换」', () => {
+  it('水位（条数 + 最大插入序）都没变时才跳过，不读 WCDB', async () => {
+    const harness = makeHarness({ messages: [imageMessage(10, 1000), imageMessage(20, 2000)] })
+    harness.watermark.count = 2
+    harness.watermark.maxLocalId = 20
+
+    await harness.service.startPass()
+    // 走到完成态需要等内部 promise 收敛。
+    await vi.waitFor(() => expect(harness.service.isRunning()).toBe(false))
+    expect(harness.listMessages).toHaveBeenCalledTimes(1)
+
+    // 第二遍：水位完全一致 → 跳过，不再读会话消息。
+    await harness.service.startPass()
+    await vi.waitFor(() => expect(harness.service.isRunning()).toBe(false))
+    expect(harness.listMessages).toHaveBeenCalledTimes(1)
+  })
+
+  it('总数相同但最大插入序前进 → 必须重扫（撤回一张旧图 + 新增一张新图）', async () => {
+    const harness = makeHarness({ messages: [imageMessage(10, 1000), imageMessage(20, 2000)] })
+    harness.watermark.count = 2
+    harness.watermark.maxLocalId = 20
+
+    await harness.service.startPass()
+    await vi.waitFor(() => expect(harness.service.isRunning()).toBe(false))
+    expect(harness.listMessages).toHaveBeenCalledTimes(1)
+
+    // 集合变了、条数没变：localId 10 被撤回，新增 localId 30。
+    harness.listMessages.mockImplementation(async () => [
+      imageMessage(20, 2000),
+      imageMessage(30, 3000)
+    ])
+    harness.watermark.maxLocalId = 30
+
+    await harness.service.startPass()
+    await vi.waitFor(() => expect(harness.service.isRunning()).toBe(false))
+    // 只看 count 的实现会在这里静默跳过 —— 那正是会漏掉新图片的洞。
+    expect(harness.listMessages).toHaveBeenCalledTimes(2)
+  })
+
+  it('水位不可用（数据库不支持该聚合）时一律重扫，宁可慢也不漏', async () => {
+    const harness = makeHarness({ messages: [imageMessage(10, 1000)] })
+    harness.watermark.count = 1
+    const service = new ImageTextIndexService()
+    const listMessages = vi.fn(async () => [imageMessage(10, 1000)])
+    service.bind({
+      databaseRoot: harness.databaseRoot,
+      resolveAccountId: () => ACCOUNT,
+      listContacts: async () => [{ md5: CONVERSATION, m_nsUsrName: 'fixture', type: 'group' }],
+      listMessages,
+      countConversationImages: async () => ({ count: 1, typeColumn: 'local_type' }),
+      // 关键：不提供 imageWatermark
+      decryptService: () => ({ findImageFile: () => null, decryptImage: () => null }) as never,
+      capability: async () => ({
+        available: true,
+        engine: 'windows-system-ocr',
+        platform: 'win32',
+        runtimeVersion: null,
+        language: null
+      })
+    })
+
+    await service.startPass()
+    await vi.waitFor(() => expect(service.isRunning()).toBe(false))
+    await service.startPass()
+    await vi.waitFor(() => expect(service.isRunning()).toBe(false))
+    expect(listMessages).toHaveBeenCalledTimes(2)
+  })
+})
+
+describe('§1 覆盖度诚实性', () => {
+  it('重启后仍是 partial：分母来自落盘统计，不会退化成 processed', async () => {
+    const { databaseRoot, databasePath } = makeHarness()
+    // 先按「已建立过索引」写库：总数 100，实际只处理了 30 条。
+    const store = new ImageTextIndexStore(databasePath, ACCOUNT)
+    store.writeCountedTotal({ total: 100, countedAt: 1_700_000_000_000, complete: true })
+    for (let index = 0; index < 30; index += 1) {
+      store.putBinding({
+        accountId: ACCOUNT,
+        conversationId: CONVERSATION,
+        messageId: `local:${index}`,
+        createTime: index,
+        imageIdentity: `sha256:${index}`,
+        artifactKey: `sha256:${index}|fake`,
+        state: 'indexed',
+        updatedAt: index
+      })
+    }
+    store.close()
+
+    // 全新 service 实例 = 模拟应用重启（内存计数器归零）。
+    const service = new ImageTextIndexService()
+    service.bind({ databaseRoot, resolveAccountId: () => ACCOUNT })
+    const status = await service.getStatus()
+
+    expect(status.coverage.totalImageMessages).toBe(100)
+    expect(status.coverage.processed).toBe(30)
+    expect(status.coverage.established).toBe(true)
+    // 修复前这里会因为 total 退化成 processed 而变成 true（把 30% 谎报成 100%）。
+    expect(status.coverage.complete).toBe(false)
+    expect(status.coverage.countedAt).toBe(1_700_000_000_000)
+  })
+
+  it('统计时有会话没数上 → 分母不完整，不允许声称 complete', async () => {
+    const { databaseRoot, databasePath } = makeHarness()
+    const store = new ImageTextIndexStore(databasePath, ACCOUNT)
+    store.writeCountedTotal({ total: 10, countedAt: 1, complete: false })
+    store.putBinding({
+      accountId: ACCOUNT,
+      conversationId: CONVERSATION,
+      messageId: 'local:1',
+      createTime: 1,
+      imageIdentity: 'sha256:1',
+      artifactKey: 'sha256:1|fake',
+      state: 'indexed',
+      updatedAt: 1
+    })
+    store.close()
+
+    const service = new ImageTextIndexService()
+    service.bind({ databaseRoot, resolveAccountId: () => ACCOUNT })
+    const status = await service.getStatus()
+    expect(status.coverage.processed).toBe(1)
+    expect(status.coverage.complete).toBe(false)
+  })
+
+  it('从未统计过 → 不算已建立，且查询路径不为看覆盖度凭空建库', async () => {
+    const { databaseRoot, databasePath } = makeHarness()
+    const service = new ImageTextIndexService()
+    service.bind({ databaseRoot, resolveAccountId: () => ACCOUNT })
+    expect(service.getCoverageSnapshot()).toBeNull()
+    expect(existsSync(databasePath)).toBe(false)
+  })
+})
+
+describe('§5 清理：删得掉才算成功', () => {
+  it('清理后派生库文件消失，覆盖度回到未建立', async () => {
+    const { service, databasePath } = makeHarness()
+    // 建一份有内容的派生数据（建库 + 写 artifact/binding/水位 + 落盘总数）。
+    const store = new ImageTextIndexStore(databasePath, ACCOUNT)
+    store.writeCountedTotal({ total: 5, countedAt: 1, complete: true })
+    store.putArtifact({
+      accountId: ACCOUNT,
+      artifactKey: 'k',
+      imageIdentity: 'sha256:x',
+      state: 'indexed',
+      text: 'fixture',
+      charCount: 7,
+      engine: 'windows-system-ocr',
+      platform: 'win32',
+      runtimeVersion: '1.2.0',
+      language: 'zh-Hans-CN',
+      createdAt: 1,
+      updatedAt: 1
+    })
+    store.close()
+    expect(existsSync(databasePath)).toBe(true)
+
+    const result = await service.clear()
+    expect(result.removed).toBe(true)
+    expect(existsSync(databasePath)).toBe(false)
+
+    const status = await service.getStatus()
+    expect(status.coverage.established).toBe(false)
+    expect(status.coverage.totalImageMessages).toBe(0)
+    expect(status.coverage.countedAt).toBeNull()
+  })
+})
+
+describe('§1/§7 查询层：覆盖度必须是独立维度且带零结果诚实性', () => {
+  const coverageOf = (input: Partial<ImageTextIndexCoverage>): ImageTextIndexCoverage => ({
+    totalImageMessages: 0,
+    processed: 0,
+    indexed: 0,
+    empty: 0,
+    missing: 0,
+    failed: 0,
+    pending: 0,
+    established: false,
+    complete: false,
+    countedAt: null,
+    ...input
+  })
+
+  it('partial：必须明确「不能因为没搜到就回答没有」并给出真实比例', () => {
+    const built = buildImageOcrCoverage(
+      coverageOf({
+        totalImageMessages: 100,
+        processed: 30,
+        indexed: 28,
+        empty: 2,
+        established: true,
+        countedAt: 1_700_000_000_000
+      })
+    )
+    expect(built?.state).toBe('partial')
+    expect(built?.totalImageMessages).toBe(100)
+    expect(built?.processed).toBe(30)
+    expect(built?.summary).toContain('30')
+    expect(built?.summary).toContain('100')
+    expect(built?.summary).toContain('不能因为没搜到就回答')
+  })
+
+  it('complete：不附加零结果约束，但仍带上统计时刻', () => {
+    const built = buildImageOcrCoverage(
+      coverageOf({
+        totalImageMessages: 100,
+        processed: 100,
+        indexed: 90,
+        empty: 10,
+        established: true,
+        complete: true,
+        countedAt: 1_700_000_000_000
+      })
+    )
+    expect(built?.state).toBe('complete')
+    expect(built?.summary).not.toContain('不能因为没搜到就回答')
+  })
+
+  it('not_built：说明图片里的文字目前搜不到，且同样禁止凭零结果下"没有"', () => {
+    const built = buildImageOcrCoverage(coverageOf({}))
+    expect(built?.state).toBe('not_built')
+    expect(built?.summary).toContain('尚未建立')
+    expect(built?.summary).toContain('不能因为没搜到就回答')
+  })
+
+  it('没有覆盖度（库都不存在）时不下发该字段，不制造假维度', () => {
+    expect(buildImageOcrCoverage(null)).toBeUndefined()
+  })
+})
+
+describe('图片数量统计：必须区分「0 张」与「统计失败」', () => {
+  function bindCounting(
+    service: ImageTextIndexService,
+    databaseRoot: string,
+    probe: () => Promise<{ count: number | null; typeColumn: string | null; error?: string }>
+  ): void {
+    service.bind({
+      databaseRoot,
+      resolveAccountId: () => ACCOUNT,
+      listContacts: async () => [
+        { md5: 'conv-a', m_nsUsrName: 'a', type: 'group' as const },
+        { md5: 'conv-b', m_nsUsrName: 'b', type: 'group' as const }
+      ],
+      countConversationImages: probe
+    })
+  }
+
+  it('真的 0 张：scanned=2 / failed=0，可以放心说 0', async () => {
+    const service = new ImageTextIndexService()
+    bindCounting(service, makeDatabaseRoot(), async () => ({
+      count: 0,
+      typeColumn: 'local_type'
+    }))
+
+    const result = await service.countImageMessages()
+    expect(result.totalImageMessages).toBe(0)
+    expect(result.scannedConversations).toBe(2)
+    expect(result.failedConversations).toBe(0)
+    expect(result.typeColumn).toBe('local_type')
+    expect(result.error).toBeUndefined()
+  })
+
+  it('统计全部失败：不得表现为 0 张，且必须给出原因', async () => {
+    const service = new ImageTextIndexService()
+    bindCounting(service, makeDatabaseRoot(), async () => ({
+      count: null,
+      typeColumn: null,
+      error: '读取消息分片失败'
+    }))
+
+    const result = await service.countImageMessages()
+    expect(result.totalImageMessages).toBe(0)
+    // 关键区分：一个会话都没数成。
+    expect(result.scannedConversations).toBe(0)
+    expect(result.failedConversations).toBe(2)
+    expect(result.error).toBe('读取消息分片失败')
+    // 统计失败 → 分母不成立 → 不允许声称已建立覆盖。
+    const status = await service.getStatus()
+    expect(status.coverage.established).toBe(false)
+    expect(status.coverage.complete).toBe(false)
+    expect(status.coverage.countedAt).not.toBeNull()
+  })
+
+  it('部分失败：总数偏小，coverage 不允许声称 complete', async () => {
+    const service = new ImageTextIndexService()
+    let call = 0
+    bindCounting(service, makeDatabaseRoot(), async () => {
+      call += 1
+      return call === 1
+        ? { count: 10, typeColumn: 'local_type' }
+        : { count: null, typeColumn: null, error: '图片消息统计查询失败' }
+    })
+
+    const result = await service.countImageMessages()
+    expect(result.totalImageMessages).toBe(10)
+    expect(result.scannedConversations).toBe(1)
+    expect(result.failedConversations).toBe(1)
+
+    const status = await service.getStatus()
+    expect(status.coverage.totalImageMessages).toBe(10)
+    expect(status.coverage.complete).toBe(false)
+  })
+
+  it('探测到的类型列名会向上透出（列名不一致时是唯一线索）', async () => {
+    const service = new ImageTextIndexService()
+    bindCounting(service, makeDatabaseRoot(), async () => ({
+      count: 3,
+      typeColumn: 'msg_type'
+    }))
+
+    const result = await service.countImageMessages()
+    expect(result.typeColumn).toBe('msg_type')
+  })
+})
diff --git a/tests/integration/image-text-index-synthetic-e2e.test.ts b/tests/integration/image-text-index-synthetic-e2e.test.ts
new file mode 100644
index 0000000..bb08645
--- /dev/null
+++ b/tests/integration/image-text-index-synthetic-e2e.test.ts
@@ -0,0 +1,389 @@
+/**
+ * §2：图片 OCR 来源语义的 **deterministic synthetic E2E**。
+ *
+ * 硬要求是"不依赖真实线上 AI 模型也能 PASS"，所以这里把两个外部边界**确定性**地固定住：
+ * - WCDB（chat-service）→ 用合成联系人 / 合成消息；
+ * - Knowledge 检索 → 用 fake 直接返回合成证据（形状与真实 `KnowledgeEvidence` 一致，
+ *   包括**未清理**的 `searchable_text`，用来验证内部前缀确实被剥掉）。
+ *
+ * 链路上真正的被测代码仍然是生产实现：
+ *   LocalQueryApiService.search()  ← 真实 scope 解析 / 证据映射 / 前缀剥离
+ *   createLocalQueryToolExecutor() ← 真实 Tool 执行
+ *   QueryAgentService.run()        ← 真实 Agent 循环 / tool result 组装
+ *
+ * 断言的 10 项对应需求：FOUND=YES / sourceKind=image / derived source=image_ocr /
+ * conversation scope=技术交流群 / Evidence messageRef=原始图片消息 /
+ * Evidence UI=图片文字 / jump target=原始图片消息 / 不产生虚构 OCR 消息。
+ */
+import { beforeEach, describe, expect, it, vi } from 'vitest'
+import { decodeMessageRef } from '../../src/shared/local-query-api'
+
+process.env.TZ = 'Asia/Shanghai'
+
+const GROUP_MD5 = 'md5-tech-group'
+const GROUP_NAME = '技术交流群'
+const IMAGE_MESSAGE_ID = 'local:9001'
+const TEXT_MESSAGE_ID = 'local:9002'
+const OCR_TEXT = 'OpenAI ChatGPT Plus $20 Pro $200'
+/** Knowledge 侧的原始 searchable_text：带内部标签，绝不该出现在 Evidence 里。 */
+const RAW_SEARCHABLE = `图片文字：${OCR_TEXT}`
+
+const fixture = vi.hoisted(() => {
+  const imageTimestamp = Date.parse('2026-09-03T14:32:00+08:00')
+  const textTimestamp = Date.parse('2026-09-03T14:30:00+08:00')
+  return {
+    imageTimestamp,
+    textTimestamp,
+    contacts: [
+      {
+        m_nsUsrName: 'wxid-tech-group',
+        m_nsNickName: '技术交流群',
+        md5: 'md5-tech-group',
+        type: 'group' as const
+      }
+    ],
+    messages: [
+      {
+        id: '9002',
+        localId: '9002',
+        from: 'user',
+        type: '文本',
+        datetime: '2026/9/3 14:30:00',
+        content: '今天正常讨论一下 API',
+        isSender: false,
+        name: '张三',
+        createTime: Math.floor(textTimestamp / 1000)
+      },
+      {
+        id: '9001',
+        localId: '9001',
+        from: 'user',
+        type: '图片',
+        datetime: '2026/9/3 14:32:00',
+        content: '',
+        contentData: { type: 'image', md5: 'image-md5-fixture', datName: 'dat-fixture' },
+        isSender: false,
+        name: '张三',
+        createTime: Math.floor(imageTimestamp / 1000)
+      }
+    ]
+  }
+})
+
+const IMAGE_TIMESTAMP = fixture.imageTimestamp
+
+vi.mock('../../src/main/services/chat-service', () => ({
+  isReady: () => true,
+  listContactsAsync: vi.fn(async () => fixture.contacts),
+  listMessagesAsync: vi.fn(async () => fixture.messages)
+}))
+
+import { LocalQueryApiService } from '../../src/main/services/local-query-api-service'
+import { createLocalQueryToolExecutor } from '../../src/main/services/local-query-tool-executor'
+import {
+  QueryAgentService,
+  type QueryAgentProvider
+} from '../../src/main/services/query-agent-service'
+
+/** 与真实 Knowledge 检索返回的证据形状一致（含原始未清理文本）。 */
+function syntheticKnowledgeEvidence() {
+  return [
+    {
+      chunkId: 'chunk-1',
+      conversationId: GROUP_MD5,
+      startTime: IMAGE_TIMESTAMP,
+      endTime: IMAGE_TIMESTAMP,
+      messageId: IMAGE_MESSAGE_ID,
+      senderId: 'fixture-member',
+      sender: '张三',
+      timestamp: IMAGE_TIMESTAMP,
+      messageIds: [IMAGE_MESSAGE_ID],
+      sourceKind: 'image' as const,
+      text: RAW_SEARCHABLE,
+      imageOcrText: OCR_TEXT,
+      derivedSource: 'image_ocr' as const
+    }
+  ]
+}
+
+function makeKnowledge() {
+  return {
+    search: vi.fn(async () => ({
+      state: 'ready',
+      evidence: syntheticKnowledgeEvidence(),
+      conversationRetrieval: { totalMessages: 2, chunkCount: 1, complete: true },
+      voiceCoverage: undefined
+    })),
+    requestCatchUp: vi.fn(() => ({ triggered: false, inProgress: false })),
+    waitForIndexingComplete: vi.fn(async () => false),
+    lastPassDurationMs: vi.fn(() => 0),
+    beginInteractiveQuery: vi.fn(),
+    endInteractiveQuery: vi.fn()
+  } as never
+}
+
+const NOW = new Date('2026-09-16T09:00:00+08:00')
+
+describe('§2 图片文字索引 synthetic E2E（确定性，不依赖真模型）', () => {
+  let knowledge: ReturnType<typeof makeKnowledge>
+  let service: LocalQueryApiService
+
+  beforeEach(() => {
+    knowledge = makeKnowledge()
+    service = new LocalQueryApiService(knowledge, () => NOW)
+  })
+
+  it('Question Tool 链路：命中图片文字的 Evidence 指向原始图片消息，且不泄露内部前缀', async () => {
+    const result = await service.search({
+      target: { query: GROUP_NAME },
+      timeRange: { kind: 'all' },
+      query: 'ChatGPT 价格',
+      variants: ['ChatGPT']
+    })
+
+    expect(result.status).toBe('completed')
+
+    // FOUND = YES
+    expect(result.evidenceCount).toBe(1)
+    expect(result.evidence).toHaveLength(1)
+    const evidence = result.evidence![0]
+
+    // sourceKind = image（原始消息是什么）
+    expect(evidence.sourceKind).toBe('image')
+    // derived source = image_ocr（靠什么搜到的）
+    expect(evidence.derivedSource).toBe('image_ocr')
+    // OCR 片段只作命中解释
+    expect(evidence.imageOcrText).toBe(OCR_TEXT)
+
+    // conversation scope = 技术交流群：target 把检索范围真正收敛到这一个会话
+    expect(result.target).toEqual({ displayName: GROUP_NAME, type: 'group' })
+    expect(evidence.conversationName).toBe(GROUP_NAME)
+    expect(evidence.conversationType).toBe('group')
+    expect(knowledge.search).toHaveBeenCalledTimes(2)
+    for (const call of knowledge.search.mock.calls) {
+      expect((call[0] as { conversationIds?: string[] }).conversationIds).toEqual([GROUP_MD5])
+    }
+
+    // sender / createTime 来自原始消息
+    expect(evidence.sender).toBe('张三')
+    expect(evidence.timestamp).toBe(IMAGE_TIMESTAMP)
+
+    // Evidence messageRef = 原始 image message（jump target 就是它）。
+    // 注意 `local:` 只是 WCDB 侧的本地 id 装饰，不属于身份本身，所以还原后是裸 id。
+    const identity = decodeMessageRef(evidence.messageRef)
+    expect(identity).toEqual({ conversationId: GROUP_MD5, messageId: '9001' })
+    // 不能产生"OCR 消息"：证据集合里不存在任何非原始消息的身份
+    expect(result.evidence!.every((item) => decodeMessageRef(item.messageRef)?.messageId === '9001')).toBe(true)
+    expect(result.evidence!.some((item) => decodeMessageRef(item.messageRef)?.messageId === '9002')).toBe(false)
+
+    // 内部前缀绝不泄露给用户（模型侧与 UI 侧都不允许）
+    expect(evidence.text).not.toContain('图片文字：')
+    expect(evidence.text).not.toContain('OCR:')
+    expect(evidence.text).not.toContain('system-ocr')
+    expect(evidence.text).toContain(OCR_TEXT)
+  })
+
+  it('Query Agent 链路：来源语义进入 tool result，OCR 片段不进模型上下文', async () => {
+    const executor = createLocalQueryToolExecutor(service)
+    const responses: Array<Awaited<ReturnType<QueryAgentProvider['chatWithTools']>>> = [
+      {
+        success: true,
+        toolCalls: [
+          {
+            id: 'call-1',
+            name: 'search_messages',
+            arguments: JSON.stringify({
+              target: { query: GROUP_NAME },
+              timeRange: { kind: 'all' },
+              queries: ['ChatGPT 价格']
+            })
+          }
+        ]
+      },
+      { success: true, data: '找到了：技术交流群发过一张 ChatGPT 价格的图片。' }
+    ]
+    const provider: QueryAgentProvider = {
+      getRuntimeConfig: () => ({
+        configured: true,
+        providerName: 'Fixture Provider',
+        model: 'fixture-model',
+        modelName: 'Fixture Model'
+      }),
+      chatWithTools: vi.fn(async () => responses.shift() || { success: true, data: 'done' })
+    }
+
+    const agentResult = await new QueryAgentService(provider, executor).run(
+      '技术交流群之前是不是发过 ChatGPT 价格的图片？'
+    )
+
+    // 模型实际看到的 tool result
+    const toolMessage = vi
+      .mocked(provider.chatWithTools)
+      .mock.calls[1]?.[0].find((message) => message.role === 'tool')
+    const presented = JSON.parse(String(toolMessage?.content)) as Record<string, any>
+    const presentedEvidence = presented.evidence?.[0]
+
+    expect(presentedEvidence.sourceKind).toBe('image')
+    expect(presentedEvidence.derivedSource).toBe('image_ocr')
+    // 片段的内容已经在 text 里，不再重复塞进上下文（避免无谓 token）。
+    expect(presentedEvidence.imageOcrText).toBeUndefined()
+    expect(presentedEvidence.text).not.toContain('图片文字：')
+    // messageRef 指向原始图片消息（模型只拿到 opaque ref，看不到会话身份）。
+    expect(decodeMessageRef(presentedEvidence.messageRef)).toEqual({
+      conversationId: GROUP_MD5,
+      messageId: '9001'
+    })
+
+    // 暴露给 UI 的证据保留来源语义与片段
+    const uiEvidence = agentResult.evidence.find((item) => item.messageRef === presentedEvidence.messageRef)
+    expect(uiEvidence?.messageType).toBe('image')
+    expect(uiEvidence?.derivedSource).toBe('image_ocr')
+    expect(uiEvidence?.imageOcrText).toBe(OCR_TEXT)
+    expect(uiEvidence?.text).not.toContain('图片文字：')
+    expect(uiEvidence?.conversationName).toBe(GROUP_NAME)
+  })
+})
+
+describe('§3 partial coverage honesty（确定性，不依赖真模型）', () => {
+  const NOT_INDEXED_KEYWORD = 'TRACE_NOT_YET_INDEXED_IMAGE'
+
+  function partialImageCoverage() {
+    return {
+      totalImageMessages: 100,
+      processed: 30,
+      indexed: 28,
+      empty: 2,
+      missing: 0,
+      failed: 0,
+      pending: 70,
+      established: true,
+      complete: false,
+      countedAt: Date.parse('2026-09-16T08:00:00+08:00')
+    }
+  }
+
+  beforeEach(() => {
+    vi.clearAllMocks()
+  })
+
+  it('已处理的 30 张里搜不到关键词时，覆盖度必须带上"不能断言没有"的语义', async () => {
+    const knowledge = makeKnowledge()
+    // 关键：已建立的 30 张里确实没有这个关键词 → 检索结果为空。
+    knowledge.search.mockImplementation(async () => ({
+      state: 'ready',
+      evidence: [],
+      // 文字索引这一维是**完整**的（噪音）：证明图片维度不会被文字维度"带过"。
+      indexLatestAt: NOW.getTime(),
+      sourceLatestAt: NOW.getTime(),
+      conversationRetrieval: { totalMessages: 2, chunkCount: 1, complete: true },
+      voiceCoverage: undefined
+    }))
+    const service = new LocalQueryApiService(knowledge, () => NOW)
+    // 图片文字索引建立过，但只完成 30 / 100。
+    service.setImageTextCoverageProvider(() => partialImageCoverage())
+
+    const result = await service.search({
+      target: { query: GROUP_NAME },
+      timeRange: { kind: 'all' },
+      query: NOT_INDEXED_KEYWORD
+    })
+
+    expect(result.status).toBe('completed')
+    expect(result.evidenceCount).toBe(0)
+    // 文字索引这一维是完整的（噪音），图片这一维才是缺口。
+    expect(result.coverage).toEqual({ state: 'complete' })
+    expect(result.imageOcrCoverage).toMatchObject({
+      state: 'partial',
+      totalImageMessages: 100,
+      processed: 30,
+      pending: 70
+    })
+    const summary = result.imageOcrCoverage!.summary
+    expect(summary).toContain('30')
+    expect(summary).toContain('100')
+    expect(summary).toContain('不能因为没搜到就回答')
+
+    // 覆盖度必须真的进入 Query Agent 的上下文，而不是只留在 Engine 里。
+    const executor = createLocalQueryToolExecutor(service)
+    const responses: Array<Awaited<ReturnType<QueryAgentProvider['chatWithTools']>>> = [
+      {
+        success: true,
+        toolCalls: [
+          {
+            id: 'call-1',
+            name: 'search_messages',
+            arguments: JSON.stringify({
+              target: { query: GROUP_NAME },
+              timeRange: { kind: 'all' },
+              queries: [NOT_INDEXED_KEYWORD]
+            })
+          }
+        ]
+      },
+      {
+        success: true,
+        data: '图片文字索引目前只处理 30 / 100 条图片消息，当前结果不完整，无法确认全部历史图片。'
+      }
+    ]
+    const provider: QueryAgentProvider = {
+      getRuntimeConfig: () => ({
+        configured: true,
+        providerName: 'Fixture Provider',
+        model: 'fixture-model',
+        modelName: 'Fixture Model'
+      }),
+      chatWithTools: vi.fn(async () => responses.shift() || { success: true, data: 'done' })
+    }
+    const agentResult = await new QueryAgentService(provider, executor).run(
+      `之前是不是有张图片写着 ${NOT_INDEXED_KEYWORD}？`
+    )
+
+    const calls = vi.mocked(provider.chatWithTools).mock.calls
+    // 提示词里写死了零结果诚实性规则（不能指望模型自己想到）。
+    expect(String(calls[0]?.[0]?.[0]?.content)).toContain('imageOcrCoverage')
+    const presented = JSON.parse(
+      String(calls[1]?.[0].find((message) => message.role === 'tool')?.content)
+    ) as Record<string, any>
+    expect(presented.evidenceCount).toBe(0)
+    expect(presented.imageOcrCoverage).toMatchObject({
+      state: 'partial',
+      totalImageMessages: 100,
+      processed: 30,
+      pending: 70
+    })
+    expect(presented.imageOcrCoverage.summary).toContain('不能因为没搜到就回答')
+
+    // 最终回答本身必须是"覆盖不完整"，不是"没有"。
+    expect(agentResult.answer).toContain('30')
+    expect(agentResult.answer).toContain('100')
+    expect(agentResult.answer).not.toBe('没有')
+  })
+
+  it('图片索引完整时不下发零结果约束（避免模型机械附加警告）', async () => {
+    const knowledge = makeKnowledge()
+    knowledge.search.mockImplementation(async () => ({
+      state: 'ready',
+      evidence: [],
+      conversationRetrieval: { totalMessages: 2, chunkCount: 1, complete: true },
+      voiceCoverage: undefined
+    }))
+    const service = new LocalQueryApiService(knowledge, () => NOW)
+    service.setImageTextCoverageProvider(() => ({
+      ...partialImageCoverage(),
+      processed: 100,
+      indexed: 98,
+      empty: 2,
+      pending: 0,
+      complete: true
+    }))
+
+    const result = await service.search({
+      target: { query: GROUP_NAME },
+      timeRange: { kind: 'all' },
+      query: NOT_INDEXED_KEYWORD
+    })
+
+    expect(result.imageOcrCoverage?.state).toBe('complete')
+    expect(result.imageOcrCoverage?.summary).not.toContain('不能因为没搜到就回答')
+  })
+})
diff --git a/tests/integration/query-agent-image-ocr-text.test.ts b/tests/integration/query-agent-image-ocr-text.test.ts
new file mode 100644
index 0000000..5c1173a
--- /dev/null
+++ b/tests/integration/query-agent-image-ocr-text.test.ts
@@ -0,0 +1,326 @@
+/**
+ * 精确读消息（`query_messages`）必须能读到**图片里识别出的文字**。
+ *
+ * 真机回归：问「我今早给文件传输助手发的那张图片里写了什么」，Query Agent 准确找到了
+ * 原始图片消息（2026/9/16 07:30:15、sender=self、type=image），却回答
+ * 「查询只返回图片附件，没有取得 OCR 文字」，甚至反过来建议用户"建立图片文字索引后再查"。
+ *
+ * 真机派生库 + Knowledge 实测结论（CASE A）：
+ *   L1 artifact  state=indexed / char_count=17
+ *   L2 binding   state=indexed
+ *   L3 Knowledge image_ocr_text 与 artifact 文本**逐字相同**，chunk 里也含该文本且指向原图 messageId
+ * —— 即"索引早就建好了，只是查询路径没把它接出来"。缺口在 L4，不在 L1/L2/L3。
+ *
+ * 这一组测试把 L4 的契约钉死：
+ *   1. 图片消息的 OCR 文本必须走 `imageOcrText` + `derivedSource=image_ocr` 独立字段；
+ *   2. 证据**永远是原始图片消息**，不许为了 OCR 文本编造一条文字消息；
+ *   3. `empty`（识别过没文字）与 `not_indexed`（还没索引）必须能被区分，
+ *      两者都不允许模型凭想象描述图片内容。
+ */
+import { beforeEach, describe, expect, it, vi } from 'vitest'
+import type { ImageTextIndexCoverage } from '../../src/shared/image-text-index'
+import { decodeMessageRef } from '../../src/shared/local-query-api'
+
+process.env.TZ = 'Asia/Shanghai'
+
+const fixture = vi.hoisted(() => {
+  const selfImageTime = Date.parse('2026-09-16T07:30:15+08:00')
+  const otherImageTime = Date.parse('2026-09-16T08:10:00+08:00')
+  return {
+    selfImageTime,
+    otherImageTime,
+    contacts: [
+      {
+        m_nsUsrName: 'filehelper',
+        m_nsNickName: '文件传输助手',
+        md5: 'md5-filehelper',
+        type: 'user' as const
+      }
+    ],
+    messages: [
+      {
+        id: '9001',
+        localId: '9001',
+        from: 'assistant',
+        // 我发出的那张图：isSender = true（自我身份来自 mesDes，不是昵称）
+        type: '图片',
+        datetime: '2026/9/16 07:30:15',
+        content: '',
+        contentData: { type: 'image', md5: 'md5-self-image', datName: 'dat-self' },
+        isSender: true,
+        name: '我',
+        createTime: Math.floor(selfImageTime / 1000)
+      },
+      {
+        id: '9002',
+        localId: '9002',
+        from: 'user',
+        type: '图片',
+        datetime: '2026/9/16 08:10:00',
+        content: '',
+        contentData: { type: 'image', md5: 'md5-other-image', datName: 'dat-other' },
+        isSender: false,
+        name: '文件传输助手',
+        createTime: Math.floor(otherImageTime / 1000)
+      }
+    ]
+  }
+})
+
+vi.mock('../../src/main/services/chat-service', () => ({
+  isReady: () => true,
+  listContactsAsync: vi.fn(async () => fixture.contacts),
+  listMessagesAsync: vi.fn(async () => fixture.messages)
+}))
+
+import { LocalQueryApiService } from '../../src/main/services/local-query-api-service'
+import { createLocalQueryToolExecutor } from '../../src/main/services/local-query-tool-executor'
+import {
+  QueryAgentService,
+  type QueryAgentProvider
+} from '../../src/main/services/query-agent-service'
+
+/** 与真实派生库同形：binding 主键 = `sourceMessageId(message)` = `local:<localId>`。 */
+const SELF_KEY = 'local:9001'
+const OTHER_KEY = 'local:9002'
+
+function coverage(overrides: Partial<ImageTextIndexCoverage> = {}): ImageTextIndexCoverage {
+  return {
+    totalImageMessages: 2,
+    processed: 2,
+    indexed: 2,
+    empty: 0,
+    missing: 0,
+    failed: 0,
+    runtimeUnavailable: 0,
+    pending: 0,
+    established: true,
+    complete: true,
+    systemicFailure: false,
+    countedAt: Date.parse('2026-09-16T09:00:00+08:00'),
+    ...overrides
+  }
+}
+
+type OcrFixture = Map<string, { state: string; text: string }>
+
+function makeService(options: { ocr?: OcrFixture; coverage?: ImageTextIndexCoverage } = {}) {
+  const knowledge = {
+    search: vi.fn(async () => ({ state: 'ready', evidence: [] })),
+    requestCatchUp: vi.fn(() => ({ triggered: false, inProgress: false })),
+    waitForIndexingComplete: vi.fn(async () => false),
+    lastPassDurationMs: vi.fn(() => 0),
+    beginInteractiveQuery: vi.fn(),
+    endInteractiveQuery: vi.fn()
+  } as never
+  const service = new LocalQueryApiService(knowledge, () => new Date('2026-09-16T09:30:00+08:00'))
+  const ocr = options.ocr ?? new Map([[SELF_KEY, { state: 'indexed', text: 'ChatGPT Plus $20' }]])
+  service.setImageOcrEntryProvider((_conversationId, messageId) => ocr.get(messageId))
+  if (options.coverage !== undefined) {
+    service.setImageTextCoverageProvider(() => options.coverage!)
+  }
+  return service
+}
+
+const askSelfImages = {
+  target: { query: '文件传输助手' },
+  timeRange: { kind: 'all' },
+  direction: 'to_target',
+  messageTypes: ['image']
+}
+
+describe('query_messages：图片消息必须携带 OCR 派生文本', () => {
+  let service: LocalQueryApiService
+  beforeEach(() => {
+    service = makeService()
+  })
+
+  it('我发出的图片带 OCR 文本时，走 imageOcrText + derivedSource，不混进 text', async () => {
+    const result = await service.messages(askSelfImages as never)
+
+    expect(result.status).toBe('completed')
+    expect(result.returnedCount).toBe(1)
+    const message = result.messages![0]
+
+    // 派生文本必须单独一个字段：混进 `text` 就无法与"群友发的文字消息"区分。
+    expect(message.imageOcrText).toBe('ChatGPT Plus $20')
+    expect(message.derivedSource).toBe('image_ocr')
+    expect(message.imageTextState).toBe('indexed')
+    expect(message.text).toBeUndefined()
+    expect(message.attachment).toEqual({ kind: 'image' })
+  })
+
+  it('对方的图片不会被贴错 OCR 文本（键必须按消息身份匹配）', async () => {
+    const result = await service.messages({
+      ...askSelfImages,
+      direction: 'from_target'
+    } as never)
+
+    expect(result.returnedCount).toBe(1)
+    // OTHER_KEY 在派生库里没有绑定 → 只能是 not_indexed，绝不能借用另一条消息的文本。
+    expect(result.messages![0].imageOcrText).toBeUndefined()
+    expect(result.messages![0].imageTextState).toBe('not_indexed')
+  })
+
+  it('识别过但图里没文字 → empty（已知结论），不是 not_indexed', async () => {
+    const empty = makeService({ ocr: new Map([[SELF_KEY, { state: 'empty', text: '' }]]) })
+    const result = await empty.messages(askSelfImages as never)
+
+    // `empty` 与 `not_indexed` 必须能分辨：前者是"已经知道没文字"，
+    // 后者是"还不知道"。把两者混起来，模型就会在没索引时断言"图里没内容"。
+    expect(result.messages![0].imageTextState).toBe('empty')
+    expect(result.messages![0].imageOcrText).toBeUndefined()
+  })
+
+  it('图片文字索引未建立时，tool result 明确带上 not_built 覆盖度', async () => {
+    const notBuilt = makeService({
+      ocr: new Map(),
+      coverage: coverage({
+        processed: 0,
+        indexed: 0,
+        pending: 0,
+        established: false,
+        complete: false
+      })
+    })
+    const result = await notBuilt.messages(askSelfImages as never)
+
+    expect(result.messages![0].imageTextState).toBe('not_indexed')
+    expect(result.imageOcrCoverage?.state).toBe('not_built')
+    expect(result.imageOcrCoverage?.summary).toContain('尚未建立')
+  })
+
+  it('覆盖度部分完成时，summary 必须说明结果可能不完整（不许当 complete）', async () => {
+    const partial = makeService({
+      coverage: coverage({
+        totalImageMessages: 100,
+        processed: 30,
+        indexed: 30,
+        pending: 70,
+        complete: false
+      })
+    })
+    const result = await partial.messages(askSelfImages as never)
+
+    expect(result.imageOcrCoverage?.state).toBe('partial')
+    expect(result.imageOcrCoverage?.summary).toContain('30')
+    expect(result.imageOcrCoverage?.summary).toContain('100')
+  })
+
+  it('普通文字消息完全不受影响（对照组）', async () => {
+    const plain = makeService({ ocr: new Map() })
+    const result = await plain.messages({
+      target: { query: '文件传输助手' },
+      timeRange: { kind: 'all' },
+      direction: 'to_target',
+      messageTypes: ['text']
+    } as never)
+
+    // 图片那两条都是 image，文字查询必然是 0 条 —— 关键是**不能**因为接了 OCR 路径
+    // 就凭空多出消息。
+    expect(result.returnedCount).toBe(0)
+  })
+})
+
+describe('Query Agent：证据永远是原始图片消息', () => {
+  function provider(
+    responses: Array<Awaited<ReturnType<QueryAgentProvider['chatWithTools']>>>
+  ): QueryAgentProvider {
+    return {
+      getRuntimeConfig: () => ({
+        configured: true,
+        providerName: 'Fixture Provider',
+        model: 'fixture-model',
+        modelName: 'Fixture Model'
+      }),
+      chatWithTools: vi.fn(async () => responses.shift() || { success: true, data: 'done' })
+    }
+  }
+
+  const selfImageArgs = JSON.stringify({
+    target: { query: '文件传输助手' },
+    timeRange: { kind: 'all' },
+    temporalBasis: { kind: 'none' },
+    direction: 'to_target',
+    messageTypes: ['image']
+  })
+
+  it('模型能在 Tool Result 里读到 imageOcrText，且证据仍指向原图 messageRef', async () => {
+    const configured = provider([
+      {
+        success: true,
+        toolCalls: [{ id: 'c1', name: 'query_messages', arguments: selfImageArgs }]
+      },
+      { success: true, data: '那张图片里的文字是 ChatGPT Plus $20。' }
+    ])
+    const service = makeService()
+    const result = await new QueryAgentService(
+      configured,
+      createLocalQueryToolExecutor(service)
+    ).run('我今早给文件传输助手发的那张图片里写了什么')
+
+    const calls = vi.mocked(configured.chatWithTools).mock.calls
+    const toolResult = JSON.parse(
+      String(calls[1]?.[0].find((message) => message.role === 'tool')?.content)
+    ) as Record<string, any>
+
+    // 1) 模型确实拿到了派生文本（这正是真机上缺的那一环）
+    expect(toolResult.messages?.[0].imageOcrText).toBe('ChatGPT Plus $20')
+    expect(toolResult.messages?.[0].derivedSource).toBe('image_ocr')
+    expect(toolResult.messages?.[0].imageTextState).toBe('indexed')
+
+    // 2) 证据只有一条，且解出来就是**原始图片消息**（不是虚构的 OCR 文字消息）
+    expect(result.evidence).toHaveLength(1)
+    expect(decodeMessageRef(result.evidence![0].messageRef)).toEqual({
+      conversationId: 'md5-filehelper',
+      messageId: '9001'
+    })
+    expect(result.evidence![0].messageType).toBe('image')
+
+    // 3) UI 拿得到来源语义（「图片文字」标记），且 snippet 不进模型上下文之外的重复字段
+    expect(result.evidence![0].derivedSource).toBe('image_ocr')
+    expect(result.evidence![0].imageOcrText).toBe('ChatGPT Plus $20')
+  })
+
+  it('系统提示词把图片文字的三态语义写死，并禁止凭空建议建立索引', async () => {
+    const scripted = provider([{ success: true, data: 'ok' }])
+    const service = makeService()
+    void new QueryAgentService(scripted, createLocalQueryToolExecutor(service)).run(
+      '我今早给文件传输助手发的那张图片里写了什么'
+    )
+
+    const systemPrompt = String(vi.mocked(scripted.chatWithTools).mock.calls[0]?.[0]?.[0]?.content)
+    expect(systemPrompt).toContain('imageOcrText')
+    // 三态必须分别说清楚
+    expect(systemPrompt).toContain('indexed')
+    expect(systemPrompt).toContain('empty')
+    expect(systemPrompt).toContain('not_indexed')
+    // OCR 不是看图：empty 时不许猜画面
+    expect(systemPrompt).toContain('OCR 不是看图')
+    // 不许无条件建议"先建立图片文字索引再查"
+    expect(systemPrompt).toContain('建立图片文字索引')
+  })
+
+  it('索引已建好的情况下，模型不会拿到任何"还没建立"的误导信号', async () => {
+    const configured = provider([
+      {
+        success: true,
+        toolCalls: [{ id: 'c1', name: 'query_messages', arguments: selfImageArgs }]
+      },
+      { success: true, data: '那张图里有 ChatGPT Plus $20。' }
+    ])
+    const service = makeService({ coverage: coverage() })
+    await new QueryAgentService(configured, createLocalQueryToolExecutor(service)).run(
+      '我今早给文件传输助手发的那张图片里写了什么'
+    )
+
+    const calls = vi.mocked(configured.chatWithTools).mock.calls
+    const toolResult = JSON.parse(
+      String(calls[1]?.[0].find((message) => message.role === 'tool')?.content)
+    ) as Record<string, any>
+
+    // 覆盖度是 complete 且带了派生文本 → 模型没有任何理由说"没有取得 OCR 文字"。
+    expect(toolResult.imageOcrCoverage?.state).toBe('complete')
+    expect(toolResult.messages?.[0].imageOcrText).toBe('ChatGPT Plus $20')
+  })
+})
diff --git a/tests/integration/query-agent-self-direction.test.ts b/tests/integration/query-agent-self-direction.test.ts
new file mode 100644
index 0000000..52e8c44
--- /dev/null
+++ b/tests/integration/query-agent-self-direction.test.ts
@@ -0,0 +1,228 @@
+/**
+ * Query Agent 的**说话人方向**语义（self sender）。
+ *
+ * 真机回归：问「我给文件传输助手发了什么图片」，planner 第一次用了 `from_target`
+ * （= 对方发来），拿到 0 条后**回头问用户"是不是方向搞错了"**，而不是自己改向重查。
+ *
+ * 代码事实：direction 的词表是**以目标会话为参照**的 ——
+ * `to_target` = 我发出的（self sender），`from_target` = 对方发来的。
+ * 所以这不是"缺一个方向取值"，而是 planner 选错了值 + 0 结果后没有利用既有重试机制。
+ */
+import { beforeEach, describe, expect, it, vi } from 'vitest'
+
+process.env.TZ = 'Asia/Shanghai'
+
+const fixture = vi.hoisted(() => {
+  const selfImageTime = Date.parse('2026-09-10T10:00:00+08:00')
+  const otherImageTime = Date.parse('2026-09-11T11:00:00+08:00')
+  return {
+    selfImageTime,
+    otherImageTime,
+    contacts: [
+      {
+        m_nsUsrName: 'filehelper',
+        m_nsNickName: '文件传输助手',
+        md5: 'md5-filehelper',
+        type: 'user' as const
+      }
+    ],
+    messages: [
+      {
+        id: '1001',
+        localId: '1001',
+        from: 'assistant',
+        // 我发出的图片：isSender = true（自我身份来自 mesDes，不是昵称）
+        type: '图片',
+        datetime: '2026/9/10 10:00:00',
+        content: '',
+        contentData: { type: 'image', md5: 'md5-self-image', datName: 'dat-self' },
+        isSender: true,
+        name: '我',
+        createTime: Math.floor(selfImageTime / 1000)
+      },
+      {
+        id: '1002',
+        localId: '1002',
+        from: 'user',
+        // 对方发来的图片
+        type: '图片',
+        datetime: '2026/9/11 11:00:00',
+        content: '',
+        contentData: { type: 'image', md5: 'md5-other-image', datName: 'dat-other' },
+        isSender: false,
+        name: '文件传输助手',
+        createTime: Math.floor(otherImageTime / 1000)
+      }
+    ]
+  }
+})
+
+vi.mock('../../src/main/services/chat-service', () => ({
+  isReady: () => true,
+  listContactsAsync: vi.fn(async () => fixture.contacts),
+  listMessagesAsync: vi.fn(async () => fixture.messages)
+}))
+
+import { LocalQueryApiService } from '../../src/main/services/local-query-api-service'
+import { createLocalQueryToolExecutor } from '../../src/main/services/local-query-tool-executor'
+import {
+  QueryAgentService,
+  type QueryAgentProvider
+} from '../../src/main/services/query-agent-service'
+
+function makeKnowledge() {
+  return {
+    search: vi.fn(async () => ({ state: 'ready', evidence: [] })),
+    requestCatchUp: vi.fn(() => ({ triggered: false, inProgress: false })),
+    waitForIndexingComplete: vi.fn(async () => false),
+    lastPassDurationMs: vi.fn(() => 0),
+    beginInteractiveQuery: vi.fn(),
+    endInteractiveQuery: vi.fn()
+  } as never
+}
+
+function makeService(): LocalQueryApiService {
+  return new LocalQueryApiService(makeKnowledge(), () => new Date('2026-09-16T09:00:00+08:00'))
+}
+
+const queryArgs = (direction: string): string =>
+  JSON.stringify({
+    target: { query: '文件传输助手' },
+    timeRange: { kind: 'all' },
+    temporalBasis: { kind: 'none' },
+    direction,
+    messageTypes: ['image']
+  })
+
+describe('direction 语义：to_target = 我发出的（self sender）', () => {
+  let service: LocalQueryApiService
+  beforeEach(() => {
+    service = makeService()
+  })
+
+  it('to_target 只返回我发出的图片，排除对方发来的', async () => {
+    const result = await service.messages({
+      target: { query: '文件传输助手' },
+      timeRange: { kind: 'all' },
+      direction: 'to_target',
+      messageTypes: ['image']
+    } as never)
+
+    expect(result.status).toBe('completed')
+    expect(result.messages?.map((message) => message.messageRef)).toHaveLength(1)
+    expect(result.messages?.[0].direction).toBe('to_target')
+    expect(result.messages?.[0].sender).toBe('我')
+    expect(result.query?.direction).toBe('to_target')
+  })
+
+  it('from_target 只返回对方发来的图片', async () => {
+    const result = await service.messages({
+      target: { query: '文件传输助手' },
+      timeRange: { kind: 'all' },
+      direction: 'from_target',
+      messageTypes: ['image']
+    } as never)
+
+    expect(result.messages).toHaveLength(1)
+    expect(result.messages?.[0].direction).toBe('from_target')
+    expect(result.messages?.[0].sender).toBe('文件传输助手')
+  })
+})
+
+describe('Query Agent：方向选反后必须自己改向重查，而不是问用户', () => {
+  function provider(
+    responses: Array<Awaited<ReturnType<QueryAgentProvider['chatWithTools']>>>
+  ): QueryAgentProvider {
+    return {
+      getRuntimeConfig: () => ({
+        configured: true,
+        providerName: 'Fixture Provider',
+        model: 'fixture-model',
+        modelName: 'Fixture Model'
+      }),
+      chatWithTools: vi.fn(async () => responses.shift() || { success: true, data: 'done' })
+    }
+  }
+
+  it('系统提示词把「我给 X 发」明确映射到 to_target，并禁止因此反问用户', () => {
+    const scripted = provider([{ success: true, data: 'ok' }])
+    const service = makeService()
+    const executor = createLocalQueryToolExecutor(service)
+    void new QueryAgentService(scripted, executor).run('我给文件传输助手发了什么图片')
+
+    const systemPrompt = String(vi.mocked(scripted.chatWithTools).mock.calls[0]?.[0]?.[0]?.content)
+    expect(systemPrompt).toContain('说话人是我 → to_target')
+    expect(systemPrompt).toContain('说话人是对方 → from_target')
+    // 提示词里明确禁止"因为方向可能错就反问用户"
+    expect(systemPrompt).toContain('要不要换个方向')
+  })
+
+  it('第一次用错方向得到 0 条 → tool result 明确要求改向重查；第二次查对 → 命中我发出的图片', async () => {
+    /**
+     * 只保留"我发出的"那一张：这样用错方向（from_target = 对方发来）必然 0 条，
+     * 才能真实复现"第一次查反了"的场景。
+     */
+    const originalMessages = fixture.messages
+    fixture.messages = [originalMessages[0]] as typeof fixture.messages
+    const configured = provider([
+      // 第一次：方向选反（对方发来）
+      { success: true, toolCalls: [{ id: 'c1', name: 'query_messages', arguments: queryArgs('from_target') }] },
+      // 第二次：改向（我发出的）
+      { success: true, toolCalls: [{ id: 'c2', name: 'query_messages', arguments: queryArgs('to_target') }] },
+      { success: true, data: '你给文件传输助手发过 1 张图片。' }
+    ])
+    const service = makeService()
+    const executor = createLocalQueryToolExecutor(service)
+    const result = await new QueryAgentService(configured, executor).run(
+      '我给文件传输助手发了什么图片'
+    )
+
+    const calls = vi.mocked(configured.chatWithTools).mock.calls
+    const firstToolResult = JSON.parse(
+      String(calls[1]?.[0].find((message) => message.role === 'tool')?.content)
+    ) as Record<string, any>
+
+    // 0 条确实发生了（说明 fixture 的方向过滤是真的在起作用）
+    expect(firstToolResult.returnedCount).toBe(0)
+    // 重试提示必须点明"方向选反"这件事，并且**禁止**反问用户
+    expect(String(firstToolResult._agent?.note)).toContain('方向选反')
+    expect(String(firstToolResult._agent?.note)).toContain('不要问用户')
+    // 重试通道仍然开放（这正是既有 zero-result retry 机制）
+    expect(firstToolResult._agent?.note).toContain('to_target')
+
+    // 取**最后一条** tool 消息：第三次调用的上下文里已经有两次 tool result。
+    const secondToolResult = JSON.parse(
+      String(
+        calls[2]?.[0].filter((message) => message.role === 'tool').at(-1)?.content
+      )
+    ) as Record<string, any>
+    expect(secondToolResult.returnedCount).toBe(1)
+    expect(secondToolResult.messages?.[0].direction).toBe('to_target')
+
+    // 最终答案基于第二次（正确方向）的结果
+    expect(result.answer).toContain('发过')
+    expect(result.toolCallCount).toBe(2)
+
+    fixture.messages = originalMessages
+  })
+
+  it('正常情况下第一次就查对：一次 tool call 命中，不需要重试', async () => {
+    const configured = provider([
+      { success: true, toolCalls: [{ id: 'c1', name: 'query_messages', arguments: queryArgs('to_target') }] },
+      { success: true, data: '你给文件传输助手发过 1 张图片。' }
+    ])
+    const service = makeService()
+    const executor = createLocalQueryToolExecutor(service)
+    const result = await new QueryAgentService(configured, executor).run(
+      '我给文件传输助手发了什么图片'
+    )
+
+    expect(result.toolCallCount).toBe(1)
+    const calls = vi.mocked(configured.chatWithTools).mock.calls
+    const toolResult = JSON.parse(
+      String(calls[1]?.[0].find((message) => message.role === 'tool')?.content)
+    ) as Record<string, any>
+    expect(toolResult.returnedCount).toBe(1)
+    expect(toolResult.messages?.[0].direction).toBe('to_target')
+  })
+})
diff --git a/tests/unit/ask-wechat-service.test.ts b/tests/unit/ask-wechat-service.test.ts
index 8225cc3..86faaa2 100644
--- a/tests/unit/ask-wechat-service.test.ts
+++ b/tests/unit/ask-wechat-service.test.ts
@@ -377,7 +377,7 @@ describe('AskWechatService — 桌面问问微信主路径', () => {
     expect(result.diagnostics.outcome).toBe('invalid_question')
   })
 
-  it('生产日志只记录形态字段，不含回答内容', async () => {
+  it('本地日志必须包含问题与模型回答原文，方便回放排查', async () => {
     const logs: AskWechatLogRecord[] = []
     const { provider } = providerFactory([answer('BOBO 最近在准备搬家，提到了房租和押金。')])
     const service = new AskWechatService(new QueryAgentService(provider, vi.fn()), {
@@ -388,17 +388,53 @@ describe('AskWechatService — 桌面问问微信主路径', () => {
     await service.ask(request('BOBO 最近在忙什么'))
 
     expect(logs).toHaveLength(1)
-    expect(Object.keys(logs[0].details ?? {}).sort()).toEqual([
-      'entry',
-      'model',
-      'modelCallCount',
-      'outcome',
-      'provider',
-      'toolCallCount',
-      'tools',
-      'totalMs'
-    ])
-    expect(JSON.stringify(logs)).not.toContain('准备搬家')
+    // 形态字段仍然一个不少（排查时既要知道"问了什么"，也要知道"跑了什么工具、多久"）。
+    for (const key of ['entry', 'model', 'modelCallCount', 'outcome', 'provider', 'toolCallCount', 'tools', 'totalMs']) {
+      expect(logs[0].details).toHaveProperty(key)
+    }
+    // 措辞回归：真机上曾出现"图片已识别出文字却答'没有取得 OCR 文字'"，
+    // 当时日志里只有工具名与次数，无法判断是索引没建还是链路没接上。
+    // 现在问答原文进入**本机**日志（不上传、不进遥测），可以直接回放。
+    expect(logs[0].details?.question).toBe('BOBO 最近在忙什么')
+    expect(String(logs[0].details?.answer)).toContain('准备搬家')
+  })
+
+  it('图片 OCR 的两条结构化事实进入诊断（不重复正文）', async () => {
+    const logs: AskWechatLogRecord[] = []
+    const { provider } = providerFactory([answer('那张图里有价格文字。')])
+    const runtime = new QueryAgentService(provider, vi.fn())
+    // 直接在 Runtime 结果里放一条带图片 OCR 的 trace，验证聚合口径。
+    vi.spyOn(runtime, 'run').mockResolvedValue({
+      question: '图里写了什么',
+      provider: 'Fixture',
+      model: 'fixture',
+      modelCallCount: 1,
+      toolCallCount: 1,
+      toolTotalMs: 5,
+      totalMs: 10,
+      modelDurationsMs: [],
+      modelDiagnostics: [],
+      answer: '那张图里有价格文字。',
+      traces: [
+        {
+          toolName: 'query_messages',
+          input: {},
+          durationMs: 5,
+          status: 'completed',
+          imageOcrTextCount: 3,
+          imageOcrCoverageState: 'partial'
+        }
+      ]
+    } as never)
+    const service = new AskWechatService(runtime, {
+      entry: 'desktop',
+      log: (record) => logs.push(record)
+    })
+
+    await service.ask(request('图里写了什么'))
+
+    expect(logs[0].details?.imageOcrTextCount).toBe(3)
+    expect(logs[0].details?.imageOcrCoverageState).toBe('partial')
   })
 
   it('forgetConversation 清掉指定会话的澄清上下文', async () => {
diff --git a/tests/unit/query-agent-image-ocr-coverage.test.ts b/tests/unit/query-agent-image-ocr-coverage.test.ts
new file mode 100644
index 0000000..2cb94e8
--- /dev/null
+++ b/tests/unit/query-agent-image-ocr-coverage.test.ts
@@ -0,0 +1,137 @@
+/**
+ * §6 / §7 / §18：图片文字索引覆盖度在 Query Agent 这一层的语义。
+ *
+ * 这里能确定性验证的是"覆盖度**真的进到了模型上下文**"，而不是只做了个 UI 数字：
+ * - 系统提示词把 imageOcrCoverage 定义成**独立于文字索引**的维度，并禁止凭零结果下"没有"；
+ * - tool result 透传里真的带着 imageOcrCoverage（模型能看见比例与结论句）。
+ *
+ * 真模型最终怎么说话不在本文件断言范围内（那需要真实模型与真实数据）。
+ */
+import { describe, expect, it, vi } from 'vitest'
+import {
+  QueryAgentService,
+  type QueryAgentProvider
+} from '../../src/main/services/query-agent-service'
+
+function provider(
+  responses: Array<Awaited<ReturnType<QueryAgentProvider['chatWithTools']>>>,
+  configured = true
+): QueryAgentProvider {
+  return {
+    getRuntimeConfig: () => ({
+      configured,
+      providerName: 'Fixture Provider',
+      model: 'fixture-model',
+      modelName: 'Fixture Model'
+    }),
+    chatWithTools: vi.fn(async () => responses.shift() || { success: true, data: 'done' })
+  }
+}
+
+/** 与 `buildImageOcrCoverage` 在 partial 时产出的结论句保持一致。 */
+const PARTIAL_SUMMARY =
+  '图片文字索引只完成 30%（30 / 100 条图片消息），当前图片搜索结果可能不完整。涉及图片、截图、海报里的文字的问题，当前不能因为没搜到就回答"没有"。'
+
+function searchOnce(execute: ReturnType<typeof vi.fn>, finalAnswer: string): QueryAgentProvider {
+  return provider([
+    {
+      success: true,
+      toolCalls: [
+        {
+          id: 'call-1',
+          name: 'search_messages',
+          arguments: JSON.stringify({
+            target: { query: '技术交流群' },
+            timeRange: { kind: 'all' },
+            queries: ['ChatGPT 价格']
+          })
+        }
+      ]
+    },
+    { success: true, data: finalAnswer }
+  ])
+}
+
+describe('Query Agent 的图片文字索引覆盖度语义', () => {
+  it('系统提示词把图片覆盖度声明为独立维度，并禁止凭零结果断言"没有"', async () => {
+    const execute = vi.fn(async () => ({ status: 'completed', evidenceCount: 0, evidence: [] }))
+    const configured = searchOnce(execute, 'ok')
+    await new QueryAgentService(configured, execute).run('图片文字索引相关的问题')
+
+    const systemPrompt = String(vi.mocked(configured.chatWithTools).mock.calls[0]?.[0]?.[0]?.content)
+    expect(systemPrompt).toContain('imageOcrCoverage')
+    expect(systemPrompt).toContain('独立于文字索引')
+    expect(systemPrompt).toContain('not_built')
+    // 零结果诚实性必须写死在提示词里，不能指望模型自己想到。
+    expect(systemPrompt).toContain('绝不能')
+  })
+
+  it('partial 覆盖度随 tool result 进入模型上下文，而不是只留在 UI 里', async () => {
+    const execute = vi.fn(async () => ({
+      status: 'completed',
+      coverage: { state: 'partial' },
+      evidenceCount: 0,
+      evidence: [],
+      imageOcrCoverage: {
+        state: 'partial',
+        totalImageMessages: 100,
+        processed: 30,
+        indexed: 28,
+        empty: 2,
+        missing: 0,
+        failed: 0,
+        pending: 70,
+        countedAtLabel: '09-15 20:13',
+        summary: PARTIAL_SUMMARY
+      }
+    }))
+    const configured = searchOnce(execute, '图片文字索引只完成 30%，暂时无法确认。')
+    await new QueryAgentService(configured, execute).run(
+      '技术交流群之前是不是发过 ChatGPT 价格的图片？'
+    )
+
+    const toolMessage = vi
+      .mocked(configured.chatWithTools)
+      .mock.calls[1]?.[0].find((message) => message.role === 'tool')
+    const presented = JSON.parse(String(toolMessage?.content)) as Record<string, any>
+
+    expect(presented.imageOcrCoverage).toMatchObject({
+      state: 'partial',
+      totalImageMessages: 100,
+      processed: 30,
+      indexed: 28,
+      empty: 2,
+      pending: 70
+    })
+    expect(presented.imageOcrCoverage.summary).toContain('不能因为没搜到就回答')
+  })
+
+  it('complete 覆盖度不下发零结果约束（避免模型机械附加警告）', async () => {
+    const execute = vi.fn(async () => ({
+      status: 'completed',
+      coverage: { state: 'complete' },
+      evidenceCount: 1,
+      evidence: [{ messageRef: 'opaque', timestamp: 1, sender: '张三', sourceKind: 'image', text: 'ChatGPT Plus $20' }],
+      imageOcrCoverage: {
+        state: 'complete',
+        totalImageMessages: 100,
+        processed: 100,
+        indexed: 90,
+        empty: 10,
+        missing: 0,
+        failed: 0,
+        pending: 0,
+        summary: '图片文字索引已覆盖所统计的全部 100 条图片消息。'
+      }
+    }))
+    const configured = searchOnce(execute, '找到了。')
+    await new QueryAgentService(configured, execute).run('技术交流群发过 ChatGPT 价格的图片吗')
+
+    const toolMessage = vi
+      .mocked(configured.chatWithTools)
+      .mock.calls[1]?.[0].find((message) => message.role === 'tool')
+    const presented = JSON.parse(String(toolMessage?.content)) as Record<string, any>
+    expect(presented.imageOcrCoverage.state).toBe('complete')
+    expect(presented.imageOcrCoverage.summary).not.toContain('不能因为没搜到就回答')
+  })
+})
diff --git a/tests/unit/wcdb-image-message-count.test.ts b/tests/unit/wcdb-image-message-count.test.ts
new file mode 100644
index 0000000..92b7f1e
--- /dev/null
+++ b/tests/unit/wcdb-image-message-count.test.ts
@@ -0,0 +1,165 @@
+/**
+ * 图片消息计数 / 增量的**标识符与列名**回归测试。
+ *
+ * 真机反馈「检测到图片消息为 0 → 无法统计（未找到该会话的消息表）」，根因有两个，
+ * 都在这里钉死：
+ *
+ * 1. **标识符混淆**：`contact.md5` 是 `md5(wxid)` 的哈希，而原生接口
+ *    （`wcdbGetMessageTableStats` / `wcdbGetMessages`）要的是**原始 username**。
+ *    把 md5 直接当 username 传，原生侧匹配不到任何表 —— 既有读消息路径一直有做这层转换
+ *    （`wechat-db.chatMd5ToUsername`、`chat-service` 的 `getUsernameByMd5`），统计路径漏了。
+ * 2. **类型列名硬编码**：不同微信版本的列名不统一（项目读行时用的是别名列表），
+ *    把 `local_type` 写进 WHERE 会在列名不同的库上抛错。
+ */
+import { createHash } from 'node:crypto'
+import { describe, expect, it, vi } from 'vitest'
+import { Wcdb4Client } from '../../src/main/wcdb4-client'
+
+const USERNAME = 'wxid_real_user'
+const ROOM = '12345678@chatroom'
+const MD5_OF_USERNAME = createHash('md5').update(USERNAME).digest('hex')
+const MD5_OF_ROOM = createHash('md5').update(ROOM).digest('hex')
+
+type ClientOptions = {
+  sessions?: { username: string }[]
+  chatTables?: { name: string; db_number: string }[] | null
+  columns?: string[]
+  count?: number
+  maxLocalId?: number
+  identifierLog?: string[]
+}
+
+function makeClient(options: ClientOptions): Wcdb4Client {
+  const identifierLog = options.identifierLog ?? []
+  return Object.assign(Object.create(Wcdb4Client.prototype), {
+    cachedSessions: (options.sessions ?? []).map((session) => ({ ...session })),
+    cachedChatTables: options.chatTables ?? null,
+    messageTypeColumnCache: new Map<string, string | null>(),
+    messageTypeColumnCandidates: [
+      'local_type',
+      'localType',
+      'msg_type',
+      'msgType',
+      'message_type',
+      'messageType',
+      'type',
+      'WCDB_CT_local_type'
+    ],
+    // 断言点：走到消息表查找时用的标识符必须是 username，不是 md5。
+    listMessageStoresAsync: vi.fn(async (identifier: string) => {
+      identifierLog.push(identifier)
+      return [{ tableName: 'Msg_fixture', dbPath: 'C:/fixture/message_0.db' }]
+    }),
+    // 聚合查询的返回（真实实现由 pickValue 解析）。
+    callJsonAsync: vi.fn(async () => [
+      { image_count: options.count ?? 0, image_max_local_id: options.maxLocalId ?? 0 }
+    ]),
+    readMessageColumns: vi.fn(() =>
+      (options.columns ?? []).map((name) => ({ name, declaration: 'INTEGER' }))
+    ),
+    wcdbGetMessageTableStats: vi.fn(async () => 0),
+    wcdbExecQuery: vi.fn(async () => 0)
+  }) as Wcdb4Client
+}
+
+describe('图片消息统计：会话标识符必须是 username 而不是 md5', () => {
+  it('从 session 能把 md5 反解成 username，并把它交给消息表查找', async () => {
+    const identifierLog: string[] = []
+    const client = makeClient({
+      sessions: [{ username: USERNAME }],
+      columns: ['local_type'],
+      count: 7,
+      identifierLog
+    })
+
+    const result = await client.countImageMessagesAsync(MD5_OF_USERNAME)
+
+    expect(result).toEqual({ count: 7, typeColumn: 'local_type' })
+    // ★ 核心回归断言：绝不能把 md5 当 username 传下去。
+    expect(identifierLog).toEqual([USERNAME])
+    expect(identifierLog).not.toContain(MD5_OF_USERNAME)
+  })
+
+  it('群聊同样走 md5 → username', async () => {
+    const identifierLog: string[] = []
+    const client = makeClient({
+      sessions: [{ username: ROOM }],
+      columns: ['local_type'],
+      count: 2,
+      identifierLog
+    })
+
+    await client.countImageMessagesAsync(MD5_OF_ROOM)
+    expect(identifierLog).toEqual([ROOM])
+  })
+
+  it('不在 session 列表、只以 Chat_<md5> 表存在的会话也能反解', async () => {
+    const identifierLog: string[] = []
+    const client = makeClient({
+      sessions: [],
+      chatTables: [{ name: `Chat_${MD5_OF_ROOM}`, db_number: ROOM }],
+      columns: ['local_type'],
+      count: 3,
+      identifierLog
+    })
+
+    const result = await client.countImageMessagesAsync(MD5_OF_ROOM)
+    expect(result.count).toBe(3)
+    expect(identifierLog).toEqual([ROOM])
+  })
+
+  it('增量水位使用同一个标识符（否则水位永远拿不到、退化成每轮重扫）', async () => {
+    const identifierLog: string[] = []
+    const client = makeClient({
+      sessions: [{ username: USERNAME }],
+      columns: ['local_type'],
+      count: 7,
+      maxLocalId: 42,
+      identifierLog
+    })
+
+    const watermark = await client.imageConversationWatermarkAsync(MD5_OF_USERNAME)
+    expect(watermark).toEqual({ count: 7, maxLocalId: 42 })
+    expect(identifierLog).toEqual([USERNAME])
+  })
+})
+
+describe('图片消息统计：类型列名随版本变化', () => {
+  it('列名不是 local_type 时照样能统计，并把真实列名透出', async () => {
+    const client = makeClient({
+      sessions: [{ username: USERNAME }],
+      columns: ['msg_type'],
+      count: 5
+    })
+
+    const result = await client.countImageMessagesAsync(MD5_OF_USERNAME)
+    expect(result).toEqual({ count: 5, typeColumn: 'msg_type' })
+  })
+
+  it('探测不到类型列时明确失败，而不是静默返回 0', async () => {
+    const client = makeClient({ sessions: [{ username: USERNAME }], columns: [] })
+
+    const result = await client.countImageMessagesAsync(MD5_OF_USERNAME)
+    // "数不出来"必须是 null + 原因，不能是 0。
+    expect(result.count).toBeNull()
+    expect(result.error).toBe('消息表缺少可识别的消息类型列')
+  })
+
+  it('一张表都没匹配到时给出可诊断的原因', async () => {
+    const client = makeClient({ sessions: [{ username: USERNAME }], columns: ['local_type'] })
+    Object.assign(client, { listMessageStoresAsync: vi.fn(async () => []) })
+
+    const result = await client.countImageMessagesAsync(MD5_OF_USERNAME)
+    expect(result.count).toBeNull()
+    expect(result.error).toBe('未找到该会话的消息表')
+  })
+
+  it('原生统计通道不可用时说明是环境问题，与 0 张区分开', async () => {
+    const client = makeClient({ sessions: [{ username: USERNAME }], columns: ['local_type'] })
+    Object.assign(client, { wcdbExecQuery: null })
+
+    const result = await client.countImageMessagesAsync(MD5_OF_USERNAME)
+    expect(result.count).toBeNull()
+    expect(result.error).toBe('当前数据服务不支持消息表统计')
+  })
+})