Debugging File Upload Failures in GPTs: GetDownloadLinkError

Debugging File Upload Failures in GPTs: GetDownloadLinkError

When trying to upload files to a GPTs Action note using uploadOpenAIFiles(), everything might look perfect — and yet it silently fails. Here's a breakdown of the common culprit: GetDownloadLinkError.

🧠 What Is GetDownloadLinkError?

This error is thrown when OpenAI's file upload system can’t retrieve or validate the download_link provided in the file reference. It typically means:

• The file wasn’t generated inside the GPT interface (like via DALL·E or /mnt/data).
• The download_link isn’t a permanent OpenAI-hosted file (e.g., expired presigned URL).
• You tried uploading a file that was only attached in the thread, not formally persisted.

🔍 How to Reproduce It (Painfully Accurately)

1. Generate an image with DALL·E.
2. Immediately try to upload it via uploadOpenAIFiles().
3. Watch it fail silently. 💥

✅ How to Fix It

1. Use a user-uploaded file instead. If the user drags and drops a file, it generates a persistent file ID like file-abc123.
2. Double-check the download_link. It must be:
   • HTTPS
   • From OpenAI's files.oaiusercontent.com
   • Not expired
3. Regenerate and reupload if the image came from DALL·E.
   • Sometimes the first image lacks a persistent download link.
   • Re-generating or saving it manually and reattaching solves the issue.

📎 Real Chat Debug Walkthrough

Click to view full debugging conversation or here's the embedded transcript:

1. User: generate an image...
2. GPT: [image generated, upload fails]
3. GPT: Tries again with persistent link
4. GPT: Still fails
5. User: uploads manually
6. GPT: Success ✅

💡 Pro Tip

Before attempting uploadOpenAIFiles(), make sure the file has a persistent ID, and if it was generated via DALL·E, always verify the download URL manually.

✦ Need to rant or debug together? You know where to find me: @goker/file-upload-error-debug-gpts

Stay sane,

— ish