My AI research workflow can't download videos. Download fails and subtitles hit 429 errors

What happened

We use an AI research workflow to study videos: it downloads a video, pulls the subtitles, and summarizes what was said and shown.

Partway through a research run, it broke in two places:

• The video download failed. It only worked again after we set a flag telling the download tool which JavaScript runtime to use.
• The subtitle fetches started failing with HTTP 429, which means "too many requests." The site was rate-limiting us.

Why it happened

Video sites change how they serve videos often, and download tools have to keep up. Sometimes the tool needs extra setup, like a specific runtime, to handle the site's newest changes. Without it, the download just fails.

The 429 errors came from asking for too much too fast. Pulling subtitles for many videos in a row looks like scraping, so the site slows you down or blocks you.

When an AI is running a workflow like this, it will often keep retrying, or tell you the video "isn't available," when the real problem is setup or rate limits.

The fix, step by step

1. Pin the tool's runtime option. Set the runtime flag in the tool's config so every run uses it, rather than fixing it by hand each time.
2. Skip subtitles when they get rate-limited. Don't retry in a tight loop. That makes 429s worse.
3. Let the AI watch the video file directly. Several assistants can now take a video file and describe both what's said and what's on screen. That replaces the subtitle step entirely.
4. Slow down batch runs. Add a pause between videos.
5. Have the workflow report the real error. "Download failed: [error]" or "429 on subtitles," not "video unavailable."

How to check it worked

• Plant a failure. Remove the runtime flag on a test run. The workflow should fail with a clear error, not a vague one.
• Run a small batch with subtitles skipped. Every video should download, and the AI's summary should cover what's on screen, not just the speech.
• Watch for 429s over a week of normal use. There should be none.