How openai handles file uploads via their API

07-12-2025

• Upload object
  • https://platform.openai.com/docs/api-reference/uploads/create
  • supported types
    • https://platform.openai.com/docs/assistants/tools/file-search#supported-files
• made up of Part objects (which contain the raw bytes)
  • https://platform.openai.com/docs/api-reference/uploads/add-part
• this gets converted into a File object on the server side