diff --git a/modules/story-summary/story-summary.js b/modules/story-summary/story-summary.js
index 3a5a0c7..9f6070f 100644
--- a/modules/story-summary/story-summary.js
+++ b/modules/story-summary/story-summary.js
@@ -1,4 +1,4 @@
-// ═══════════════════════════════════════════════════════════════════════════
+// ═══════════════════════════════════════════════════════════════════════════
 // Story Summary - 主入口
 //
 // 稳定目标：
@@ -91,7 +91,7 @@ import {
 // vector io
 import { exportVectors, importVectors } from "./vector/storage/vector-io.js";
 
-import { invalidateLexicalIndex, warmupIndex } from "./vector/retrieval/lexical-index.js";
+import { invalidateLexicalIndex, warmupIndex, addDocumentsForFloor, removeDocumentsByFloor, addEventDocuments } from "./vector/retrieval/lexical-index.js";
 
 // ═══════════════════════════════════════════════════════════════════════════
 // 常量
@@ -351,9 +351,12 @@ async function handleAnchorGenerate() {
         });
 
         postToFrame({ type: "ANCHOR_GEN_PROGRESS", current: 0, total: 1, message: "向量化 L1..." });
-        await buildIncrementalChunks({ vectorConfig: vectorCfg });
+        const chunkResult = await buildIncrementalChunks({ vectorConfig: vectorCfg });
 
-        invalidateLexicalIndex();
+        // L1 rebuild only if new chunks were added (usually 0 in normal chat)
+        if (chunkResult.built > 0) {
+            invalidateLexicalIndex();
+        }
 
         await sendAnchorStatsToFrame();
         await sendVectorStatsToFrame();
@@ -589,8 +592,6 @@ function refreshEntityLexiconAndWarmup() {
     injectEntities(lexicon, displayMap);
 
     // 异步预建词法索引（不阻塞）
-    invalidateLexicalIndex();
-    warmupIndex();
 }
 
 // ═══════════════════════════════════════════════════════════════════════════
@@ -615,9 +616,12 @@ async function maybeAutoExtractL0() {
         await incrementalExtractAtoms(chatId, chat, null, { maxFloors: 20 });
 
         // 为新提取的 L0 楼层构建 L1 chunks
-        await buildIncrementalChunks({ vectorConfig: vectorCfg });
+        const chunkResult = await buildIncrementalChunks({ vectorConfig: vectorCfg });
 
-        invalidateLexicalIndex();
+        // L1 rebuild only if new chunks were added
+        if (chunkResult.built > 0) {
+            invalidateLexicalIndex();
+        }
 
         await sendAnchorStatsToFrame();
         await sendVectorStatsToFrame();
@@ -637,7 +641,7 @@ async function maybeAutoExtractL0() {
 function warmupEmbeddingConnection() {
     const vectorCfg = getVectorConfig();
     if (!vectorCfg?.enabled) return;
-    embed(['.'], vectorCfg, { timeout: 5000 }).catch(() => {});
+    embed(['.'], vectorCfg, { timeout: 5000 }).catch(() => { });
 }
 
 async function autoVectorizeNewEvents(newEventIds) {
@@ -1043,7 +1047,12 @@ async function autoRunSummaryWithRetry(targetMesId, configForRun) {
                     const store = getSummaryStore();
                     postToFrame({ type: "SUMMARY_FULL_DATA", payload: buildFramePayload(store) });
 
-                    invalidateLexicalIndex();
+                    // Incrementally add new events to the lexical index
+                    if (newEventIds?.length) {
+                        const allEvents = store?.json?.events || [];
+                        const idSet = new Set(newEventIds);
+                        addEventDocuments(allEvents.filter(e => idSet.has(e.id)));
+                    }
 
                     applyHideStateDebounced();
                     updateFrameStatsAfterSummary(endMesId, store.json || {});
@@ -1150,7 +1159,7 @@ function handleFrameMessage(event) {
         case "VECTOR_CANCEL_GENERATE":
             vectorCancelled = true;
             cancelL0Extraction();
-            try { vectorAbortController?.abort?.(); } catch {}
+            try { vectorAbortController?.abort?.(); } catch { }
             postToFrame({ type: "VECTOR_GEN_PROGRESS", phase: "ALL", current: -1, total: 0 });
             break;
 
@@ -1338,7 +1347,12 @@ async function handleManualGenerate(mesId, config) {
                 const store = getSummaryStore();
                 postToFrame({ type: "SUMMARY_FULL_DATA", payload: buildFramePayload(store) });
 
-                invalidateLexicalIndex();
+                // Incrementally add new events to the lexical index
+                if (newEventIds?.length) {
+                    const allEvents = store?.json?.events || [];
+                    const idSet = new Set(newEventIds);
+                    addEventDocuments(allEvents.filter(e => idSet.has(e.id)));
+                }
 
                 applyHideStateDebounced();
                 updateFrameStatsAfterSummary(endMesId, store.json || {});
@@ -1381,6 +1395,10 @@ async function handleChatChanged() {
     // 实体词典注入 + 索引预热
     refreshEntityLexiconAndWarmup();
 
+    // Full lexical index rebuild on chat change
+    invalidateLexicalIndex();
+    warmupIndex();
+
     // Embedding 连接预热（保持 TCP keep-alive，减少首次召回超时）
     warmupEmbeddingConnection();
 
@@ -1421,7 +1439,7 @@ async function handleMessageSwiped() {
         await deleteStateVectorsFromFloor(chatId, lastFloor);
     }
 
-    invalidateLexicalIndex();
+    removeDocumentsByFloor(lastFloor);
 
     initButtonsForAll();
     applyHideStateDebounced();
@@ -1437,22 +1455,28 @@ async function handleMessageReceived() {
 
     initButtonsForAll();
 
-    // 向量全量生成中时跳过 L1 sync（避免竞争写入）
+    // Skip L1 sync while full vector generation is running
     if (guard.isRunning('vector')) return;
 
-    await syncOnMessageReceived(chatId, lastFloor, message, vectorConfig, () => {
+    const syncResult = await syncOnMessageReceived(chatId, lastFloor, message, vectorConfig, () => {
         sendAnchorStatsToFrame();
         sendVectorStatsToFrame();
     });
+
+    // Incrementally update lexical index with built chunks (avoid re-read)
+    if (syncResult?.chunks?.length) {
+        addDocumentsForFloor(lastFloor, syncResult.chunks);
+    }
+
     await maybeAutoBuildChunks();
 
     applyHideStateDebounced();
     setTimeout(() => maybeAutoRunSummary("after_ai"), 1000);
 
-    // 新消息后刷新实体词典（可能有新角色）
+    // Refresh entity lexicon after new message (new roles may appear)
     refreshEntityLexiconAndWarmup();
 
-    // 自动补提取缺失的 L0（延迟执行，避免与当前楼提取竞争）
+    // Auto backfill missing L0 (delay to avoid contention with current floor)
     setTimeout(() => maybeAutoExtractL0(), 2000);
 }
 
@@ -1578,19 +1602,19 @@ async function handleGenerationStarted(type, _params, isDryRun) {
 // ═══════════════════════════════════════════════════════════════════════════
 
 const boundHandlers = {
-    chatChanged:       () => setTimeout(handleChatChanged, 80),
-    messageDeleted:    () => setTimeout(handleMessageDeleted, 50),
-    messageReceived:   () => setTimeout(handleMessageReceived, 150),
-    messageSent:       () => setTimeout(handleMessageSent, 150),
+    chatChanged: () => setTimeout(handleChatChanged, 80),
+    messageDeleted: () => setTimeout(handleMessageDeleted, 50),
+    messageReceived: () => setTimeout(handleMessageReceived, 150),
+    messageSent: () => setTimeout(handleMessageSent, 150),
     messageSentRecall: handleMessageSentForRecall,
-    messageSwiped:     () => setTimeout(handleMessageSwiped, 100),
-    messageUpdated:    () => setTimeout(handleMessageUpdated, 100),
-    messageEdited:     () => setTimeout(handleMessageUpdated, 100),
-    userRendered:      (data) => setTimeout(() => handleMessageRendered(data), 50),
-    charRendered:      (data) => setTimeout(() => handleMessageRendered(data), 50),
-    genStarted:        handleGenerationStarted,
-    genStopped:        clearExtensionPrompt,
-    genEnded:          clearExtensionPrompt,
+    messageSwiped: () => setTimeout(handleMessageSwiped, 100),
+    messageUpdated: () => setTimeout(handleMessageUpdated, 100),
+    messageEdited: () => setTimeout(handleMessageUpdated, 100),
+    userRendered: (data) => setTimeout(() => handleMessageRendered(data), 50),
+    charRendered: (data) => setTimeout(() => handleMessageRendered(data), 50),
+    genStarted: handleGenerationStarted,
+    genStopped: clearExtensionPrompt,
+    genEnded: clearExtensionPrompt,
 };
 
 function registerEvents() {
@@ -1686,4 +1710,4 @@ jQuery(() => {
     initStateIntegration();
 
     maybePreloadTokenizer();
-});
+});
\ No newline at end of file