diff --git a/apps/api/app/api/routes/scripts_ai.py b/apps/api/app/api/routes/scripts_ai.py
index fc48dc10d..a1daf8179 100644
--- a/apps/api/app/api/routes/scripts_ai.py
+++ b/apps/api/app/api/routes/scripts_ai.py
@@ -101,7 +101,11 @@ else:
         DOUYIN_COOKIES_FILE_BAKED,
     )
 
-_DOUYIN_DEBUG_ERRORS = os.environ.get("DOUYIN_DEBUG_ERRORS", "").lower() in ("1", "true", "yes")
+_DOUYIN_DEBUG_ERRORS = os.environ.get("DOUYIN_DEBUG_ERRORS", "").lower() in (
+    "1",
+    "true",
+    "yes",
+) or os.environ.get("APP_ENV", "").lower() in ("staging", "dev", "development", "test")
 
 _URL_EXTRACT_RE = re.compile(r"https?://\S+", re.IGNORECASE)
 _DOUYIN_HOST_RE = re.compile(
@@ -307,7 +311,7 @@ def _fetch_ttwid():
     # 方式一：直接调 ttwid 注册接口
     try:
         with httpx.Client(timeout=8, follow_redirects=True, verify=False) as http:
-            http.post(
+            r = http.post(
                 "https://ttwid.bytedance.com/ttwid/union/register/",
                 json={
                     "region": "cn",
@@ -442,6 +446,7 @@ def _ytdlp_extract_video_url(page_url, cookiefile=None, max_retries=10):
     import time as _time
 
     ttwid = _fetch_ttwid()
+    logger.info("ytdlp 直链提取开始: page_url=%s ttwid_ok=%s max_retries=%d", page_url, bool(ttwid), max_retries)
     with tempfile.TemporaryDirectory(prefix="dy_ytdlp_cookies_") as tmpdir:
         for attempt in range(max_retries):
             if attempt % 3 == 0:
@@ -450,8 +455,9 @@ def _ytdlp_extract_video_url(page_url, cookiefile=None, max_retries=10):
             info, err = _ytdlp_try_extract(page_url, gen_cookie)
             if info:
                 vurl = info.get("url")
-                logger.info("yt-dlp 合成 cookie 第%d次尝试成功", attempt + 1)
+                logger.info("yt-dlp 合成 cookie 第%d次尝试成功: vurl_domain=%s", attempt + 1, vurl.split("/")[2] if vurl and "/" in vurl else "?")
                 return (vurl, float(info.get("duration") or 0.0)) if vurl else (None, 0.0)
+            logger.info("yt-dlp 合成 cookie 第%d次尝试失败: %s", attempt + 1, str(err)[:150])
             _time.sleep(0.4)
 
         logger.info("yt-dlp 合成 cookie 全部 %d 次重试均失败", max_retries)
@@ -717,7 +723,7 @@ def _ytdlp_download_and_local_asr(page_url, temp_dir, cookiefile=None):
         cookie_files_to_try.append(cookiefile)
 
     # 2. 合成 cookie 重试（复用 _ytdlp_extract 的 cookie 生成逻辑，8次重试）
-    import time as _time
+    import secrets, time as _time
     ttwid = _fetch_ttwid()
     for i in range(8):
         if i % 3 == 0:
@@ -731,11 +737,21 @@ def _ytdlp_download_and_local_asr(page_url, temp_dir, cookiefile=None):
             vpath, duration = _download(cfile)
             if vpath and os.path.isfile(vpath) and os.path.getsize(vpath) > 0:
                 break
+            logger.warning(
+                "ytdlp 下载返回路径无效或空文件: vpath=%s size=%s",
+                vpath,
+                os.path.getsize(vpath) if vpath and os.path.isfile(vpath) else "N/A",
+            )
         except Exception as exc:  # noqa: BLE001
             last_err = exc
+            logger.warning("ytdlp 下载重试失败: %s", str(exc)[:200])
             continue
     else:
         msg = str(last_err) if last_err else "unknown"
+        logger.warning(
+            "ytdlp 下载全部 %d 次 cookie 尝试均失败: ttwid_ok=%s last_err=%s",
+            len(cookie_files_to_try), bool(ttwid), msg[:300],
+        )
         if _is_cookies_related_error(msg) or "Fresh cookies" in msg:
             _detail = "抖音链接解析暂时不可用，请稍后重试或手动输入文案"
             if _DOUYIN_DEBUG_ERRORS: