diff --git a/src/app/api/messages/[messageId]/route.ts b/src/app/api/messages/[messageId]/route.ts
new file mode 100644
index 0000000..b9a79cf
--- /dev/null
+++ b/src/app/api/messages/[messageId]/route.ts
@@ -0,0 +1,119 @@
+import { NextResponse } from 'next/server';
+import { db } from '@/drizzle/db';
+import { messages } from '@/drizzle/schema';
+import { eq } from 'drizzle-orm';
+
+interface RouteParams {
+  params: Promise<{ messageId: string }>;
+}
+
+/**
+ * PATCH /api/messages/[messageId] - 更新消息
+ * 主要用于更新消息的图片数据（Pyodide 执行后保存图片）
+ */
+export async function PATCH(request: Request, { params }: RouteParams) {
+  try {
+    const { messageId } = await params;
+    const body = await request.json();
+
+    // 验证 messageId
+    if (!messageId) {
+      return NextResponse.json(
+        { error: 'Message ID is required' },
+        { status: 400 }
+      );
+    }
+
+    // 查找消息
+    const existingMessage = await db.query.messages.findFirst({
+      where: eq(messages.messageId, messageId),
+    });
+
+    if (!existingMessage) {
+      return NextResponse.json(
+        { error: 'Message not found' },
+        { status: 404 }
+      );
+    }
+
+    // 构建更新数据
+    const updateData: {
+      images?: string[];
+      content?: string;
+      updatedAt: Date;
+    } = {
+      updatedAt: new Date(),
+    };
+
+    // 更新图片（追加模式）
+    if (body.images && Array.isArray(body.images)) {
+      const existingImages = (existingMessage.images as string[]) || [];
+      updateData.images = [...existingImages, ...body.images];
+    }
+
+    // 更新内容（如果提供）
+    if (body.content !== undefined) {
+      updateData.content = body.content;
+    }
+
+    // 执行更新
+    await db
+      .update(messages)
+      .set(updateData)
+      .where(eq(messages.messageId, messageId));
+
+    // 返回更新后的消息
+    const updatedMessage = await db.query.messages.findFirst({
+      where: eq(messages.messageId, messageId),
+    });
+
+    return NextResponse.json({
+      success: true,
+      message: updatedMessage,
+    });
+  } catch (error) {
+    console.error('Update message error:', error);
+    return NextResponse.json(
+      { error: 'Failed to update message' },
+      { status: 500 }
+    );
+  }
+}
+
+/**
+ * GET /api/messages/[messageId] - 获取单个消息
+ */
+export async function GET(request: Request, { params }: RouteParams) {
+  try {
+    const { messageId } = await params;
+
+    if (!messageId) {
+      return NextResponse.json(
+        { error: 'Message ID is required' },
+        { status: 400 }
+      );
+    }
+
+    const message = await db.query.messages.findFirst({
+      where: eq(messages.messageId, messageId),
+    });
+
+    if (!message) {
+      return NextResponse.json(
+        { error: 'Message not found' },
+        { status: 404 }
+      );
+    }
+
+    return NextResponse.json({
+      success: true,
+      message,
+    });
+  } catch (error) {
+    console.error('Get message error:', error);
+    return NextResponse.json(
+      { error: 'Failed to get message' },
+      { status: 500 }
+    );
+  }
+}