OpenAI API · api · fg-0144

Uploaded PDF rejected: Expected a file with an application/pdf MIME type, but got unsupported MIME type 'None'

Invalid file data: 'file_id'. Expected a file with an application/pdf MIME type, but got unsupported MIME type 'None'.

Verified 2026-10-15 · Confirmed by 0 builders · Trust 50/100

Cause

Uploading raw bytes without a filename or content type stores the file with no MIME type, and the model input path refuses it.

Fix

Upload with a filename and content type tuple and purpose user_data, then use the new file id.

Apply

f = client.files.create(file=("document.pdf", pdf_bytes, "application/pdf"), purpose="user_data")

Affects: openai-python and other SDKs uploading bytes for PDF inputs, confirmed by maintainers 2026-09-10

Sources

• https://github.com/openai/openai-python/issues/2472

claude mcp add --transport http footgun https://getfootgun.com/api/mcp