Hane Cowork
Attaching files
How to attach files to requests in Hane Cowork, preview them before sending, where attachments are sent, and format and size limits.
This page explains how to attach files to a request, how to check their contents before sending, and where attachments go in work on this PC and in Platform conversations.
Recorded in the actual Hane Cowork app (connected to a test Platform with scripted model responses). The app UI is in Japanese; English captions explain each step.
Attaching
Section titled “Attaching”You can attach files to the draft in the request box in any of these ways:
- Press the paper clip button (「ファイルを添付する」, Attach a file) and choose files
- Drop files onto the Cowork window (「ファイルをドロップして添付」, Drop files to attach, appears)
- Paste copied files into the request box
You can also attach the text of a shared Chrome page. Use the globe button in the request box (「Chrome のページを添付する」, Attach a Chrome page) (Use your everyday Chrome).
Drafts with attachments are saved on the device, so they survive switching screens or reloading the app. To remove an attachment, press its 「添付から外す」 (Remove from attachments) button.
Checking contents before sending
Section titled “Checking contents before sending”Press an attachment in the draft to open its contents without changing the draft.
| Format | Preview before sending |
|---|---|
| Text (UTF-8) | Shown on the device. For long files, only the beginning is shown, with a notice |
| Shown on the device. You can move between pages | |
| Office documents and images | Not yet supported before sending. Check the file name and size |
Opening a preview does not send the file to Platform.
Attachments in sent messages can be opened the same way. In Platform conversations, Cowork fetches the original of the version attached when you sent it. Office documents are shown as the PDF that Platform converted. 「元のファイルを保存」 (Save original file) saves the original, and for Office documents, 「表示した PDF を保存」 (Save displayed PDF) saves the converted PDF.
Where attachments go
Section titled “Where attachments go”How attachments are handled depends on the kind of work.
| Work | Formats you can attach | Destination |
|---|---|---|
| Work on this PC (「新しい作業」, New work) | Text, images, PDF, Office documents (docx, xlsx, pptx) | Not registered as Platform documents. Text and images are passed as they are; for PDF and Office documents, the text is extracted on the device. Both go to the harness’s work area |
| Platform conversations | PDF, Office documents, text | Uploaded to the Platform documents API when you send, and attached to the conversation message. Images cannot be sent |
Even in work on this PC, when the harness passes file contents to the model, those contents reach the model through Platform’s Model Gateway. Platform call records do not store request or attachment text, or file names.
Attachments in work on this PC
Section titled “Attachments in work on this PC”- For PDF and Office documents (docx, xlsx, pptx), Cowork extracts only the text on the device and passes it to the harness. Layout, images, and figures are not passed. For Excel, the values in each sheet are extracted; for PowerPoint, the text in slide order.
- Text cannot be extracted from password-protected documents or image-only PDFs that contain no text. In that case Cowork shows 「添付した文書から本文を取り出せませんでした。」 (Could not extract text from the attached document) and does not send.
- Old-format Office documents (doc, xls, ppt) cannot be read. Save them again as docx, xlsx, pptx, or PDF.
- Images (png, jpg, webp, gif) are passed to the harness as they are. Whether the model can read images depends on the model your organization allows for Cowork.
If sending fails, your draft is kept. Text files already in the work folder can be read without attaching them; just name them in the request.
Attachments in Platform conversations
Section titled “Attachments in Platform conversations”Images cannot be sent to Platform conversations. If you attach one, Cowork shows 「画像は新しい作業（この PC での作業）で添付してください。」 (Attach images in new work, that is, work on this PC) and does not send.
Limits
Section titled “Limits”| Item | Limit |
|---|---|
| Formats | PDF, Office documents (docx, xlsx, pptx, doc, xls, ppt), text (txt, md, csv, tsv, json, log), images (png, jpg, jpeg, webp, gif) |
| Formats by kind of work | Work on this PC cannot read doc, xls, or ppt. Images cannot be sent to Platform conversations |
| Count | Up to 5 per draft |
| Size | Up to 10 MB per file. Empty files cannot be attached |
| Text encoding | UTF-8 |
| Request text | Up to 4,000 characters. Attach longer content as a file |
What stays on the device
Section titled “What stays on the device”Attachments waiting to be sent are copied into the app data. In 「機能と接続 → 端末のデータ」 (Features and connections → Device data), you can check the number and size of cached attachments and press 「未使用の添付を削除」 (Delete unused attachments) to remove copies not used by history or drafts.
Only copies saved by Cowork are deleted. Original files, work results, and documents and conversations sent to Platform are not deleted.