diff --git a/src/components/ai/GuidancePanel.vue b/src/components/ai/GuidancePanel.vue
index 66ff54b..10fd531 100644
--- a/src/components/ai/GuidancePanel.vue
+++ b/src/components/ai/GuidancePanel.vue
@@ -84,8 +84,8 @@
 
 <script setup lang="ts">
 import { ref, computed, watch, nextTick } from "vue"
-import { marked } from "marked"
 import { Icon } from "@iconify/vue"
+import { renderMarkdown } from "../../utils/markdown"
 import {
   messages,
   streaming,
@@ -110,10 +110,6 @@ const displayStreamingContent = computed(() =>
   streamingContent.value.replace(/^\[READY\]\n?/, "")
 )
 
-function renderMarkdown(text: string): string {
-  return marked.parse(text) as string
-}
-
 function send() {
   const text = draftPrompt.value.trim()
   if (!text || streaming.value) return
diff --git a/src/components/ai/PromptHistoryPanel.vue b/src/components/ai/PromptHistoryPanel.vue
index 9d58b02..ab0b2bc 100644
--- a/src/components/ai/PromptHistoryPanel.vue
+++ b/src/components/ai/PromptHistoryPanel.vue
@@ -75,17 +75,36 @@
                 {{ item.source === "manual" ? "手动提交" : "AI 对话" }}
               </n-tag>
             </n-flex>
-            <n-tag
-              v-if="selectedAssistantMessageId === item.assistant_message_id"
-              size="small"
-              type="success"
-              :bordered="false"
-            >
-              正在预览
-            </n-tag>
-            <n-text depth="3">
-              {{ parseTime(item.created, "YYYY-MM-DD HH:mm") }}
-            </n-text>
+            <n-flex align="center" :wrap="false" :size="4">
+              <n-tag
+                v-if="selectedAssistantMessageId === item.assistant_message_id"
+                size="small"
+                type="success"
+                :bordered="false"
+              >
+                正在预览
+              </n-tag>
+              <n-text depth="3">
+                {{ parseTime(item.created, "YYYY-MM-DD HH:mm") }}
+              </n-text>
+              <n-tooltip placement="top">
+                <template #trigger>
+                  <n-button
+                    quaternary
+                    circle
+                    size="small"
+                    :loading="deletingId === item.assistant_message_id"
+                    :disabled="deletingId !== null"
+                    @click="deleteItem(item, $event)"
+                  >
+                    <template #icon>
+                      <Icon icon="lucide:trash-2" />
+                    </template>
+                  </n-button>
+                </template>
+                删除这条历史对话
+              </n-tooltip>
+            </n-flex>
           </n-flex>
           <div
             class="prompt-markdown markdown-body"
@@ -112,7 +131,8 @@
 <script setup lang="ts">
 import { onMounted, ref, watch } from "vue"
 import { Icon } from "@iconify/vue"
-import { marked } from "marked"
+import { useMessage } from "naive-ui"
+import { renderMarkdown } from "../../utils/markdown"
 import { Prompt } from "../../api"
 import type { PromptHistoryItem } from "../../utils/type"
 import { parseTime } from "../../utils/helper"
@@ -127,6 +147,7 @@ const props = defineProps<{
 
 const emit = defineEmits<{
   select: [code: { html: string; css: string; js: string }]
+  deleted: [assistantMessageId: number]
 }>()
 
 type HistoryViewItem = PromptHistoryItem & {
@@ -137,7 +158,11 @@ type HistoryViewItem = PromptHistoryItem & {
 const items = ref<HistoryViewItem[]>([])
 const loading = ref(false)
 const selectedAssistantMessageId = ref<number | null>(null)
+const deletingId = ref<number | null>(null)
 let loadedTaskId = 0
+let pendingRefresh = false
+
+const naiveMessage = useMessage()
 
 function toViewItem(item: PromptHistoryItem): HistoryViewItem {
   const html = item.code_html ?? ""
@@ -155,8 +180,25 @@ function toViewItem(item: PromptHistoryItem): HistoryViewItem {
   }
 }
 
-function renderMarkdown(text: string): string {
-  return marked.parse(text) as string
+async function deleteItem(item: HistoryViewItem, e: Event) {
+  e.stopPropagation()
+  if (deletingId.value !== null) return
+  deletingId.value = item.assistant_message_id
+  try {
+    await Prompt.deleteMessagePair(item.assistant_message_id)
+    items.value = items.value.filter(
+      (i) => i.assistant_message_id !== item.assistant_message_id,
+    )
+    if (selectedAssistantMessageId.value === item.assistant_message_id) {
+      selectedAssistantMessageId.value = null
+    }
+    emit("deleted", item.assistant_message_id)
+    naiveMessage.success("已删除")
+  } catch {
+    naiveMessage.error("删除失败，请重试")
+  } finally {
+    deletingId.value = null
+  }
 }
 
 function selectItem(item: HistoryViewItem) {
@@ -194,7 +236,14 @@ async function load(force = true) {
 watch(
   () => [props.active, props.taskId] as const,
   ([active]) => {
-    if (active) load(false)
+    if (active) {
+      if (pendingRefresh) {
+        pendingRefresh = false
+        load(true)
+      } else {
+        load(false)
+      }
+    }
   },
 )
 
@@ -202,6 +251,7 @@ watch(
   () => props.refreshKey,
   () => {
     if (props.active) load(true)
+    else pendingRefresh = true
   },
 )
 
@@ -243,6 +293,7 @@ onMounted(() => {
   overflow: hidden;
 }
 
+
 .history-card.is-selected {
   --n-color: #f7fffa;
   box-shadow: 0 10px 24px rgba(24, 160, 88, 0.14);
diff --git a/src/components/ai/PromptPanel.vue b/src/components/ai/PromptPanel.vue
index fbe2d13..17f0abb 100644
--- a/src/components/ai/PromptPanel.vue
+++ b/src/components/ai/PromptPanel.vue
@@ -100,7 +100,6 @@
 <script setup lang="ts">
 import { ref, watch, nextTick, computed } from "vue"
 import { useStorage } from "@vueuse/core"
-import { marked, Renderer } from "marked"
 import { useMessage } from "naive-ui"
 import { Icon } from "@iconify/vue"
 import GuidancePanel from "./GuidancePanel.vue"
@@ -113,8 +112,12 @@ import {
   sendPrompt,
   stopPrompt,
   currentTaskId,
+  removeMessagePair,
 } from "../../store/prompt"
 import { Prompt } from "../../api"
+import { renderMarkdown } from "../../utils/markdown"
+
+const emit = defineEmits<{ deleted: [] }>()
 
 const input = ref("")
 const messagesRef = ref<HTMLElement>()
@@ -151,11 +154,9 @@ const pairs = computed(() => {
 async function deletePair(assistantMsgId: number) {
   try {
     await Prompt.deleteMessagePair(assistantMsgId)
-    const msgIdx = messages.value.findIndex((m) => m.id === assistantMsgId)
-    if (msgIdx >= 1) {
-      messages.value.splice(msgIdx - 1, 2)
-    }
+    removeMessagePair(assistantMsgId)
     naiveMessage.success("已删除")
+    emit("deleted")
   } catch {
     naiveMessage.error("删除失败，请重试")
   }
@@ -179,56 +180,6 @@ function onGuidanceGenerate(finalPrompt: string) {
   input.value = ""
 }
 
-const renderer = new Renderer()
-renderer.code = function ({ lang }: { text: string; lang?: string }) {
-  const label = lang ? lang.toUpperCase() : "CODE"
-  const colors: Record<
-    string,
-    { bg: string; fg: string; dot: string; border: string; shimmer: string }
-  > = {
-    html: {
-      bg: "#f0fff4",
-      fg: "#18a058",
-      dot: "#18a058",
-      border: "#b8e8cc",
-      shimmer: "#f0fff4, #e0f7ea, #f0fff4",
-    },
-    css: {
-      bg: "#f0f0ff",
-      fg: "#6060d0",
-      dot: "#6060d0",
-      border: "#d0d0f0",
-      shimmer: "#f0f0ff, #e8e8fa, #f0f0ff",
-    },
-    js: {
-      bg: "#fffbf0",
-      fg: "#c0960a",
-      dot: "#c0960a",
-      border: "#f0e0b0",
-      shimmer: "#fffbf0, #fff5e0, #fffbf0",
-    },
-    javascript: {
-      bg: "#fffbf0",
-      fg: "#c0960a",
-      dot: "#c0960a",
-      border: "#f0e0b0",
-      shimmer: "#fffbf0, #fff5e0, #fffbf0",
-    },
-  }
-  const c = colors[(lang ?? "").toLowerCase()] ?? {
-    bg: "#f0f7ff",
-    fg: "#2080f0",
-    dot: "#2080f0",
-    border: "#e0eaf5",
-    shimmer: "#f0f7ff, #e8f4f8, #f0f7ff",
-  }
-  return `<div class="code-placeholder" style="background: linear-gradient(90deg, ${c.shimmer}); background-size: 200% 100%; border-color: ${c.border}"><span class="code-placeholder-dot" style="background: ${c.dot}"></span><span class="code-placeholder-label" style="color: ${c.fg}; background: ${c.fg}18">${label}</span><span class="code-placeholder-text">代码正在生成中，结束后会自动应用到预览区</span></div>`
-}
-
-function renderMarkdown(text: string): string {
-  return marked.parse(text, { renderer }) as string
-}
-
 function renderContent(msg: { role: string; content: string }): string {
   return renderMarkdown(msg.content)
 }
@@ -289,47 +240,6 @@ watch([() => messages.value.length, streamingContent], () => {
   font-size: 13px;
 }
 
-.message-content :deep(.code-placeholder) {
-  display: flex;
-  align-items: center;
-  gap: 8px;
-  padding: 10px 14px;
-  margin: 8px 0;
-  background: linear-gradient(90deg, #f0f7ff, #e8f4f8, #f0f7ff);
-  background-size: 200% 100%;
-  animation: shimmer 2s ease-in-out infinite;
-  border-radius: 6px;
-  border: 1px solid #e0eaf5;
-}
-
-.message-content :deep(.code-placeholder-dot) {
-  width: 8px;
-  height: 8px;
-  border-radius: 50%;
-  background: #2080f0;
-  animation: pulse 1.5s ease-in-out infinite;
-}
-
-.message-content :deep(.code-placeholder-label) {
-  font-size: 11px;
-  font-weight: 600;
-  padding: 1px 6px;
-  border-radius: 3px;
-}
-
-.message-content :deep(.code-placeholder-text) {
-  font-size: 12px;
-  color: #888;
-}
-
-@keyframes shimmer {
-  0% {
-    background-position: -200% 0;
-  }
-  100% {
-    background-position: 200% 0;
-  }
-}
 
 @keyframes pulse {
   0%,
diff --git a/src/pages/ChallengeDetail.vue b/src/pages/ChallengeDetail.vue
index 679eca6..fc8f2a0 100644
--- a/src/pages/ChallengeDetail.vue
+++ b/src/pages/ChallengeDetail.vue
@@ -49,7 +49,7 @@
           </div>
         </n-tab-pane>
         <n-tab-pane name="chat" tab="AI 对话" display-directive="show">
-          <PromptPanel />
+          <PromptPanel @deleted="historyRefreshKey++" />
         </n-tab-pane>
         <n-tab-pane name="external" tab="手动提交" display-directive="show">
           <ExternalAIPanel :task-id="taskId" @submitted="historyRefreshKey++" />
@@ -61,6 +61,7 @@
             :asset-base-url="assetBaseUrl"
             :refresh-key="historyRefreshKey"
             @select="previewHistoryItem"
+            @deleted="removeMessagePair"
           />
         </n-tab-pane>
       </n-tabs>
@@ -139,6 +140,7 @@ import {
   disconnectPrompt,
   streaming,
   setOnCodeComplete,
+  removeMessagePair,
 } from "../store/prompt"
 
 const route = useRoute()
@@ -193,14 +195,17 @@ async function loadChallenge() {
   const display = Number(route.params.display)
   taskTab.value = TASK_TYPE.Challenge
   challengeDisplay.value = display
-  const data = await Challenge.get(display)
+  const [data, fetchedAssets] = await Promise.all([
+    Challenge.get(display),
+    TaskAssets.listChallenge(display),
+  ])
   taskId.value = data.task_ptr
   challengeAuthor.value = data.author_name ?? ""
   challengeContent.value = await marked.parse(data.content, {
     async: true,
     renderer: challengeRenderer,
   } as MarkedOptions)
-  assets.value = await TaskAssets.listChallenge(display)
+  assets.value = fetchedAssets
   if (!authed.value) return
   connectPrompt(data.task_ptr)
   setOnCodeComplete(async (code, messageId) => {
diff --git a/src/store/prompt.ts b/src/store/prompt.ts
index 3b4ec28..22cacd0 100644
--- a/src/store/prompt.ts
+++ b/src/store/prompt.ts
@@ -28,10 +28,8 @@ export function setOnCodeComplete(fn: typeof _onCodeComplete) {
 }
 
 let ws: WebSocket | null = null
-let _currentTaskId = 0
 
 export function connectPrompt(taskId: number) {
-  _currentTaskId = taskId
   currentTaskId.value = taskId
   if (ws) ws.close()
 
@@ -102,7 +100,6 @@ export function disconnectPrompt() {
   streaming.value = false
   streamingContent.value = ""
   currentTaskId.value = 0
-  _currentTaskId = 0
   _onCodeComplete = null
 }
 
@@ -122,8 +119,15 @@ export function stopPrompt() {
   }
   streaming.value = false
   streamingContent.value = ""
-  if (_currentTaskId) {
-    connectPrompt(_currentTaskId)
+  if (currentTaskId.value) {
+    connectPrompt(currentTaskId.value)
+  }
+}
+
+export function removeMessagePair(assistantMsgId: number) {
+  const idx = messages.value.findIndex((m) => m.id === assistantMsgId)
+  if (idx >= 1) {
+    messages.value.splice(idx - 1, 2)
   }
 }
 
diff --git a/src/utils/markdown.ts b/src/utils/markdown.ts
new file mode 100644
index 0000000..e73428b
--- /dev/null
+++ b/src/utils/markdown.ts
@@ -0,0 +1,5 @@
+import { marked } from "marked"
+
+export function renderMarkdown(text: string): string {
+  return marked.parse(text) as string
+}