yt_dlp YoutubeDL works locally but fails on Render with "Sign in to confirm you're not a bot"

I'm building a Flask backend that downloads audio from YouTube using yt_dlp.
Locally, everything works perfectly. But when I deploy the same code to Render, the /import-youtube route returns a 500 error.

Here is my simplified route:

@app.route('/import-youtube', methods=['POST']) def import_youtube(): data = request.get_json(silent=True) or {} url = data.get("url") ydl_opts = { "format": "bestaudio/best", "postprocessors": [{ "key": "FFmpegExtractAudio", "preferredcodec": "mp3", "preferredquality": "192", }], "outtmpl": os.path.join(DOWNLOADS_DIR, "%(title)s.%(ext)s"), } try: with yt_dlp.YoutubeDL(ydl_opts) as ydl: info = ydl.extract_info(url, download=True) except Exception as e: app.logger.error("YouTube import failed", exc_info=True) return jsonify({"error": str(e)}), 500

What fails on Render

The logs show:

yt_dlp.utils.DownloadError: ERROR: [youtube] <video-id>: Sign in to confirm you’re not a bot. Use --cookies-from-browser or --cookies for authentication.

Locally on my machine this never happens.

My environment

Python 3.13 (Render)

Flask

yt_dlp 2024.x

FFmpeg installed in the Render environment

Using Gunicorn: gunicorn FindSongsBackEnd.app:app

My question

Why does yt_dlp require “Sign in to confirm you’re not a bot” only on Render, while the exact same code works locally?

Is there a recommended way to avoid this error when running yt_dlp on cloud hosting providers (Render, AWS, etc.)?

I’m specifically looking for:

Whether this is an IP / rate-limit issue.

Whether there is a way to configure yt_dlp to avoid this error without passing browser cookies.

Or whether the correct approach is to catch DownloadError and handle this case as a non-recoverable response.

Any guidance or prior experience with yt_dlp on cloud hosts would be appreciated.