> ## Documentation Index
> Fetch the complete documentation index at: https://docs.overcontrolgroup.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Files and images

> Summarize documents, review text, and ask questions about images in Chat.

Bring your own context into [OverControl Chat](https://chat.overcontrolgroup.com) by attaching a document or image to your message. Ask for a summary, a comparison, an explanation, or a specific detail from the attachment. You do not need an API key.

## Supported attachments

| Attachment | Formats | How Chat uses it |
| - | - | - |
| Images | JPEG, PNG, WebP | **Vision** reads the image content. |
| Text | Plain text, Markdown, CSV, JSON | Chat extracts text for **Fast**, **Expert**, or **Vision** to use. |
| PDFs | PDFs with extractable text | Chat extracts text. PDF page images, layout, and embedded diagrams are not analyzed as images. |

Office documents, archives, audio, and video are not currently supported as Chat attachments. Export a document to a supported text format or a PDF with selectable text before uploading it.

For a scanned PDF, provide clear JPEG, PNG, or WebP images of the relevant pages and choose **Vision**. A PDF that contains only scanned images may have no text for Chat to extract.

## Attach and ask

**1. Choose a mode**

Open Chat and select **Vision** for images. Choose **Fast** for a document summary or **Expert** for a more detailed review.

**2. Add your files**

Use the attachment control in the message composer. Wait for the upload to finish before sending your message.

**3. Describe the result you need**

Ask a question that refers to the attachment. When using several files, identify them by name and explain how they relate.

**4. Review and refine**

Check important details against the original files. Ask follow-up questions in the same conversation while the relevant content remains available.

For a document:

```text theme={null}
Compare the two attached proposals. Create a table of scope, deadlines, and open questions.
Use only the supplied files and mark anything that is not specified.
```

For an image:

```text theme={null}
Describe the chart in this image. Identify the main trend and any labels you can read.
Say when a value is too small or unclear to interpret.
```

## Attachment limits

| Limit | Current value |
| - | - |
| Files per message | 3 |
| File size | 5 MiB per file |
| Combined attachment size | 10 MiB; the upload request must also fit the service's request-size limit |
| Text supplied per file | Up to 12,000 tokens; longer extracted text can be truncated |
| Attachment context | Up to 10 MiB of file data and 60,000 characters of extracted text |
| Image preparation | Images may be resized to fit within 1,280 × 1,280 pixels before upload |

A MiB is 1,048,576 bytes. Upload size and extracted-text size are different limits: a small PDF can still contain too much text. Long conversations also use context, so a successful upload does not mean an entire document will fit in every follow-up request.

For long documents, upload the relevant section or split the work across focused conversations. For images with small text, crop to the area you want analyzed before attaching it.

## Solve common attachment problems

| What happens | What to check |
| - | - |
| File type is rejected | Use one of the supported formats above. Renaming an extension does not convert a file. |
| Upload is too large | Reduce each file below 5 MiB and keep the combined size comfortably below 10 MiB to leave room for the upload request. |
| PDF has no readable content | Check that its text is selectable. For scanned pages, attach images and choose Vision. |
| Extraction or context limit is reached | Use a shorter excerpt or fewer documents. Start a fresh conversation for a separate document set. |
| An image answer misses small details | Choose Vision and upload a clear crop. Resizing can make small text harder to read. |
| Upload is temporarily rate limited | Let the current upload finish, wait, and try again with fewer files. Avoid repeated rapid retries. |
| An earlier attachment is unavailable | It may have expired or been deleted. Reattach a copy if you still have the original. |

## Storage and deletion

Attachments are stored so they can be used in your conversation; closing a tab does not delete them. Chat currently applies a **30-day retention period**, with attachment expiry handled separately from conversation expiry.

Removing an attachment from the message composer prevents it from being sent in that message. To manage stored uploads, open **Settings**, find **Manage Files** under the data controls, and use **Manage**. Deleting a conversation does not by itself guarantee immediate deletion of every uploaded file.

See [Privacy and security](https://docs.overcontrolgroup.com/chat/privacy-security.md) for the distinction between conversation deletion, attachment deletion, and automatic expiry. Chat attachments are separate from files uploaded through the developer API.


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