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askdareDocumentation

    Attachments

    Visitors can attach images and PDFs to their messages. The model sees images and reads PDFs (their text and page images).

    Turn it on

    defineBot({
  // …
  attachments: {}, // images and PDFs, up to 4 MB, 3 per message
});
    OptionDefaultMeaning
    imagestruePNG, JPEG, WebP and GIF
    pdftruePDF documents
    maxBytes4_000_000Largest file. 4 MB fits Vercel's 4.5 MB request body limit; raise it only on hosts without one
    maxPerMessage3Files per message (up to 10)
    maxPdfPages50Longest PDF accepted

    Uploads are limited per visitor and per IP per hour (limits.uploadsPerVisitorPerHour, default 20; limits.uploadsPerIpPerHour, default 60) and per bot per day (limits.uploadsPerDay, default 500). Files that are uploaded but never sent cost no tokens, but they take up storage in your OpenAI project until they expire.

    What the widget does

    • A paperclip button opens the file picker. Files can also be pasted or dropped onto the chat.
    • Images are downsized to 2048 px on the long edge and re-encoded as JPEG in the browser. That keeps uploads small, drops EXIF data such as the GPS position, and converts HEIC photos where the browser can decode them.
    • Each file is uploaded as soon as it is chosen; the message is sent once every upload has finished.

    What the server does

    • Detects the type from the file's bytes, never from its name or Content-Type. SVG, animated GIFs and anything else are refused.
    • Uploads the file to OpenAI with purpose user_data. Files expire after 30 days, and are deleted earlier when the visitor deletes the conversation.
    • Returns an encrypted handle instead of the OpenAI file ID. Handles are bound to the bot and the visitor and expire after 1 hour.
    • Reserves tokens for the files before the turn: about 1,500 per image and 2,000 per PDF page. Pages are counted from the file itself, including compressed object streams; a PDF whose pages can't be counted is charged as if it had maxPdfPages pages. When the bot has tools, the reservation covers every model call the turn may make, because each call reads the files again.

    After a page reload the conversation shows how many files a message had, not the files themselves: OpenAI does not let you download user_data files.

    Privacy

    Uploaded files are stored by OpenAI under your project until they expire or are deleted. Mention this in your privacy policy, and keep attachments off for bots that don't need them.