diff --git a/nginx/nginx.conf b/nginx/nginx.conf
index b4d4f68..937e1d6 100644
--- a/nginx/nginx.conf
+++ b/nginx/nginx.conf
@@ -160,18 +160,36 @@ http {
                     -- 记录请求体大小，方便调试
                     ngx.log(ngx.INFO, "Received body size: ", string.len(body))
                     
+                    -- 调试：保存请求体到文件以便分析
+                    local debug_file = io.open("/tmp/last_request_body.json", "w")
+                    if debug_file then
+                        debug_file:write(body)
+                        debug_file:close()
+                        ngx.log(ngx.INFO, "Request body saved to /tmp/last_request_body.json")
+                    end
+                    
                     -- 解析 JSON
                     local ok, data = pcall(cjson.decode, body)
                     if not ok then
                         -- 记录解析错误的详细信息
                         ngx.log(ngx.ERR, "JSON parse error: ", data)
                         ngx.log(ngx.ERR, "Body preview (first 500 chars): ", string.sub(body, 1, 500))
+                        
+                        -- 保存出错的位置附近的内容
+                        local error_pos = tonumber(string.match(tostring(data), "character (%d+)"))
+                        if error_pos then
+                            local start_pos = math.max(1, error_pos - 100)
+                            local end_pos = math.min(string.len(body), error_pos + 100)
+                            ngx.log(ngx.ERR, "Error context (chars ", start_pos, "-", end_pos, "): ", string.sub(body, start_pos, end_pos))
+                        end
+                        
                         ngx.status = 400
                         ngx.say(cjson.encode({
                             error = "Invalid JSON",
                             details = tostring(data),
                             body_size = string.len(body),
-                            body_preview = string.sub(body, 1, 200)
+                            body_preview = string.sub(body, 1, 200),
+                            error_position = error_pos
                         }))
                         return
                     end