diff --git a/formatMessages.mjs b/formatMessages.mjs
index 3be6bd0..a42d846 100644
--- a/formatMessages.mjs
+++ b/formatMessages.mjs
@@ -1,10 +1,23 @@
-export function formatMessages(messages) {
+export function formatMessages(messages, proxyModel) {
+    function convertToUpperCase(messages) {
+        return messages.map(message => {
+            let content = message.content;
+
+            content = content.replace(/^(system|assistant|user):/gim, match => match.toUpperCase());
+            content = content.replace(/\n(system|assistant|user|human):/gim, (match, p1) => '\n' + p1.toUpperCase() + ':');
+
+            const role = message.role.toUpperCase();
+
+            return { role, content };
+        });
+    }
+
     // 检查是否存在 "<!-- AI Round 0 begins. -->" 标记
     const hasAIRound0 = messages.some(message => message.content.includes('<!-- AI Round 0 begins. -->'));
-    
+
     // 如果没有找到标记，直接返回原始消息数组
     if (!hasAIRound0) {
-        return messages;
+        return proxyModel === 'gpt_4o' ? convertToUpperCase(messages) : messages;
     }
 
     let formattedMessages = [];
@@ -12,7 +25,6 @@ export function formatMessages(messages) {
     let assistantRoundCounter = 0;
     let descriptionPointCounter = 0;
     let isFirstUserFound = false;
-    let isLatestRound = false;
     let lastAssistantRound = 0;
 
     // 查找初始回合数
@@ -34,6 +46,21 @@ export function formatMessages(messages) {
         }
     }
 
+    // 找到包含 </context> --- 的消息索引
+    let contextEndIndex = messages.length;
+    for (let i = 0; i < messages.length; i++) {
+        if (messages[i].content.includes('</context> ---')) {
+            contextEndIndex = i;
+            break;
+        }
+    }
+
+    // 找到最后一个 user 消息的索引（在 </context> --- 之前）
+    let lastUserIndex = contextEndIndex - 1;
+    while (lastUserIndex >= 0 && messages[lastUserIndex].role !== 'user') {
+        lastUserIndex--;
+    }
+
     for (let i = 0; i < messages.length; i++) {
         const message = messages[i];
 
@@ -45,46 +72,40 @@ export function formatMessages(messages) {
             continue;
         }
 
-        if (message.role === 'user') {
+        if (message.role === 'user' && i < contextEndIndex) {
             if (isFirstUserFound) {
                 userRoundCounter = lastAssistantRound + 1;
                 descriptionPointCounter++;
             } else {
                 isFirstUserFound = true;
             }
-            
+
             let roundInfo = '';
-            if (i + 1 < messages.length && messages[i + 1].role === 'assistant') {
+            if (i === lastUserIndex) {
+                roundInfo = `{{最新user:(${userRoundCounter})回合|assistant:(${userRoundCounter + 1})回合开始，基于上回(${descriptionPointCounter - 1}(user${userRoundCounter - 1}|assistant${userRoundCounter}))中的历史锚点内的\`assistant:\`发言末尾衔接，叙事创作时不要只关注最近故事动向，尽可能的记住多个历史锚点中的"assistant:..."故事内容，保持思路清晰来响应下一个回复:}}\n`;
+            } else {
                 const nextAssistantRound = userRoundCounter + 1;
                 roundInfo = `{{历史第 user = 回合${userRoundCounter}|assistant = 回合${nextAssistantRound} 开始，标记锚点:[${descriptionPointCounter}]}}\n`;
-            } else {
-                isLatestRound = true;
-                roundInfo = `{{最新user:(${userRoundCounter})回合|assistant:(${userRoundCounter + 1})回合开始，基于上回(${descriptionPointCounter - 1}(user${userRoundCounter - 1}|assistant${userRoundCounter}))中的历史锚点内的\`assistant:\`发言末尾衔接，叙事创作时不要只关注最近故事动向，尽可能的记住多个历史锚点中的"assistant:..."故事内容，保持思路清晰来响应下一个回复:}}\n`;
             }
-            formattedMessages.push({
-                role: 'system',
-                content: roundInfo
-            });
-        } else if (message.role === 'assistant') {
+            message.content = roundInfo + message.content;
+        } else if (message.role === 'assistant' && i < contextEndIndex) {
             const match = message.content.match(/<!-- AI Round (\d+) begins\. -->/);
             if (match) {
                 assistantRoundCounter = parseInt(match[1]);
                 lastAssistantRound = assistantRoundCounter;
             }
+
+            if (message.content.includes('<CHAR_turn>') && i < lastUserIndex) {
+                message.content += `\n--------------------<历史锚点[${descriptionPointCounter}]结束>--------------------`;
+            }
         }
 
         formattedMessages.push(message);
+    }
 
-        if (message.content.includes('<CHAR_turn>') && !isLatestRound) {
-            formattedMessages.push({
-                role: 'system',
-                content: `--------------------<历史锚点[${descriptionPointCounter}]结束>--------------------`
-            });
-        }
-
-        if (message.content.includes('<!-- The following are the writing style rules and guidelines for the turn-based collaborative storytelling: -->')) {
-            break;
-        }
+    // 如果 proxyModel 是 gpt_4o，则转换消息前缀为大写
+    if (proxyModel === 'gpt_4o') {
+        formattedMessages = convertToUpperCase(formattedMessages);
     }
 
     return formattedMessages;