diff --git a/frontend/app/web-gold/src/api/agent.js b/frontend/app/web-gold/src/api/agent.js
index c04bcd0f81..06a92e746d 100644
--- a/frontend/app/web-gold/src/api/agent.js
+++ b/frontend/app/web-gold/src/api/agent.js
@@ -21,10 +21,11 @@ export function getAgentList() {
 /**
  * 流式对话（SSE）
  * @param {Object} options - 请求配置
- * @param {number} options.agentId - 智能体ID
+ * @param {number} [options.agentId] - 智能体ID（使用 customSystemPrompt 时可不传）
  * @param {string} options.content - 用户输入内容
  * @param {string} [options.conversationId] - 会话ID（可选，首次对话不传）
  * @param {string} [options.modelMode] - 模型模式：pro-深度版 standard-标准版
+ * @param {string} [options.customSystemPrompt] - 自定义系统提示词（使用用户自建风格时传入）
  * @param {AbortController} [options.ctrl] - 取消控制器
  * @param {Function} options.onMessage - 消息回调
  * @param {Function} [options.onError] - 错误回调
@@ -36,6 +37,7 @@ export async function sendChatStream(options) {
     content,
     conversationId,
     modelMode = 'pro',
+    customSystemPrompt,
     ctrl,
     onMessage,
     onError,
@@ -56,7 +58,8 @@ export async function sendChatStream(options) {
       agentId,
       content,
       conversationId,
-      modelMode
+      modelMode,
+      customSystemPrompt
     }),
     onmessage: (event) => {
       if (typeof onMessage === 'function') {
diff --git a/frontend/app/web-gold/src/components/agents/ChatDrawer.vue b/frontend/app/web-gold/src/components/agents/ChatDrawer.vue
index 6e829a77af..b31bece763 100644
--- a/frontend/app/web-gold/src/components/agents/ChatDrawer.vue
+++ b/frontend/app/web-gold/src/components/agents/ChatDrawer.vue
@@ -123,7 +123,8 @@ const executeStreamRequest = async (prompt) => {
 
   try {
     await sendChatStream({
-      agentId: props.agent?.id,
+      agentId: props.agent?.customSystemPrompt ? undefined : props.agent?.id,
+      customSystemPrompt: props.agent?.customSystemPrompt,
       content: prompt,
       modelMode: modelMode.value,
       ctrl: abortController.value,
@@ -170,7 +171,7 @@ watch(() => props.visible, (val) => {
 
 <template>
   <Sheet :open="visible" @update:open="handleClose">
-    <SheetContent side="right" class="w-full sm:w-[420px] md:w-[560px] lg:w-[640px] p-0 flex flex-col bg-background">
+    <SheetContent side="right" class="w-full sm:w-[520px] md:w-[680px] lg:w-[800px] p-0 flex flex-col bg-background">
       <!-- Header -->
       <SheetHeader class="shrink-0">
         <ChatDrawerHeader :agent="agent" @history="openHistory" />
diff --git a/frontend/app/web-gold/src/components/agents/MyFavoritesModal.vue b/frontend/app/web-gold/src/components/agents/MyFavoritesModal.vue
index ca493675e8..86c321c9a1 100644
--- a/frontend/app/web-gold/src/components/agents/MyFavoritesModal.vue
+++ b/frontend/app/web-gold/src/components/agents/MyFavoritesModal.vue
@@ -60,6 +60,7 @@ async function loadList() {
       promptList.value = res.data.map(item => ({
         id: item.id,
         name: item.name,
+        content: item.content,
         category: item.category,
         useCount: item.useCount || 0
       }))
@@ -95,7 +96,8 @@ function handleUse(item) {
   emit('chat', {
     id: item.id,
     name: item.name,
-    categoryName: item.category || '我的风格'
+    categoryName: item.category || '我的风格',
+    customSystemPrompt: item.content
   })
   handleClose()
 }
diff --git a/yudao-module-tik/src/main/java/cn/iocoder/yudao/module/tik/dify/service/DifyServiceImpl.java b/yudao-module-tik/src/main/java/cn/iocoder/yudao/module/tik/dify/service/DifyServiceImpl.java
index 4f26dd380b..1911622915 100644
--- a/yudao-module-tik/src/main/java/cn/iocoder/yudao/module/tik/dify/service/DifyServiceImpl.java
+++ b/yudao-module-tik/src/main/java/cn/iocoder/yudao/module/tik/dify/service/DifyServiceImpl.java
@@ -50,13 +50,24 @@ public class DifyServiceImpl implements DifyService {
         AtomicLong pendingRecordId = new AtomicLong();
         AtomicReference<String> conversationIdRef = new AtomicReference<>(reqVO.getConversationId());
         AtomicReference<DifyChatRespVO> tokenUsageRef = new AtomicReference<>();
-        String difyUserId = "user-" + userId + "-agent-" + reqVO.getAgentId();
+        String difyUserId = reqVO.getAgentId() != null
+                ? "user-" + userId + "-agent-" + reqVO.getAgentId()
+                : "user-" + userId + "-prompt";
         String logPrefix = "chatStream";
 
         return Mono.fromCallable(() -> {
-                    AiAgentDO agent = aiAgentService.getAiAgent(reqVO.getAgentId());
-                    if (agent == null) {
-                        throw new RuntimeException("智能体不存在");
+                    // 解析系统提示词：优先使用自定义提示词，否则从智能体获取
+                    String systemPrompt;
+                    if (reqVO.getCustomSystemPrompt() != null && !reqVO.getCustomSystemPrompt().isEmpty()) {
+                        systemPrompt = reqVO.getCustomSystemPrompt();
+                    } else if (reqVO.getAgentId() != null) {
+                        AiAgentDO agent = aiAgentService.getAiAgent(reqVO.getAgentId());
+                        if (agent == null) {
+                            throw new RuntimeException("智能体不存在");
+                        }
+                        systemPrompt = agent.getSystemPrompt();
+                    } else {
+                        throw new RuntimeException("必须提供 agentId 或 customSystemPrompt");
                     }
 
                     AiModelTypeEnum modelTypeEnum = "standard".equals(reqVO.getModelMode())
@@ -66,12 +77,15 @@ public class DifyServiceImpl implements DifyService {
                             AiPlatformEnum.DIFY.getPlatform(), modelTypeEnum.getModelCode());
 
                     pointsService.checkPoints(userId, config.getConsumePoints());
+                    String serviceRef = reqVO.getAgentId() != null
+                            ? reqVO.getAgentId().toString()
+                            : "custom-prompt";
                     Long recordId = pointsService.createPendingDeduct(
                             userId, config.getConsumePoints(), "dify_chat",
-                            reqVO.getAgentId().toString(), config.getServiceCode());
+                            serviceRef, config.getServiceCode());
                     pendingRecordId.set(recordId);
 
-                    return new DifyChatContext(agent.getSystemPrompt(), config.getApiKey(), config.getConsumePoints());
+                    return new DifyChatContext(systemPrompt, config.getApiKey(), config.getConsumePoints());
                 })
                 .flatMapMany(context -> difyClient.chatStream(
                                 context.apiKey(), reqVO.getContent(), context.systemPrompt(),
diff --git a/yudao-module-tik/src/main/java/cn/iocoder/yudao/module/tik/dify/vo/DifyChatReqVO.java b/yudao-module-tik/src/main/java/cn/iocoder/yudao/module/tik/dify/vo/DifyChatReqVO.java
index fca17dafbf..2da2ef9d82 100644
--- a/yudao-module-tik/src/main/java/cn/iocoder/yudao/module/tik/dify/vo/DifyChatReqVO.java
+++ b/yudao-module-tik/src/main/java/cn/iocoder/yudao/module/tik/dify/vo/DifyChatReqVO.java
@@ -12,8 +12,7 @@ import lombok.Data;
 @Data
 public class DifyChatReqVO {
 
-    @Schema(description = "智能体ID", requiredMode = Schema.RequiredMode.REQUIRED)
-    @NotNull(message = "智能体ID不能为空")
+    @Schema(description = "智能体ID（使用 customSystemPrompt 时可不传）")
     private Long agentId;
 
     @Schema(description = "用户输入内容", requiredMode = Schema.RequiredMode.REQUIRED)
@@ -26,4 +25,7 @@ public class DifyChatReqVO {
     @Schema(description = "模型模式：pro-深度版 standard-标准版", example = "pro")
     private String modelMode = "pro";
 
+    @Schema(description = "自定义系统提示词（使用用户自建风格时传入）")
+    private String customSystemPrompt;
+
 }