Work item data is made of typed columns, and two of those types hold files: File and Image. The same two types are available for the inputs and outputs of a tool, so a file can be passed into a tool and a new file handed back out.
Choosing File rather than plain Text for a column that holds a document link is worth doing. A Text column holds a string that happens to look like a link. A File column is understood by the platform: it renders as an openable document, it can be filled from a file picker, it tells agents what kind of file to expect, and it controls whether agents are allowed to change that file.
The File type
A File value is a link to a document. It can point at a file in Google Drive, in OneDrive or SharePoint, at a file uploaded from a local drive, or at any other reachable URL.
When someone fills in a File value in the product, they get the standard picker — Local file system, Google Drive, SharePoint / OneDrive — or they can paste a link directly. When an AI agent fills it in, it supplies the URL of the file it produced or found.
Constraints on a File column
Every column type has constraints; these are the ones that matter for File.
Constraint | What it does |
Single value / List of values | Whether the column holds one file or several. A list is the right choice for "supporting documents"; a single value for "the signed contract". |
File type | The kind of file this column is expected to hold: Excel spreadsheet (.xlsx), Google Sheet, CSV, Word document (.docx), Google Doc, PDF, or PowerPoint (.pptx). Optional — leave it blank when the column can hold anything. |
Access | Whether a tool may modify this file in place (Read / write) or only read it (Read only). |
Computed by an AI agent | Whether an AI agent is expected to produce this value rather than a person supplying it. |
Required | Whether the work item is incomplete without it. |
Sensitive data | Hides the value in the UI by default. |
Why Access matters
Access is the constraint people underuse, and it is the one that prevents the most damage.
Set a File column to Read only and the platform will not let agents modify that file in place. When an agent opens a file that a step declared read-only, the tools that would change it — append a row, update a row, add a column, append to a document — are simply not offered to the agent for that file. The tools that only read it stay available, and so do the tools that create a new file, such as exporting to PDF or creating a new workbook.
This is a much stronger guarantee than an instruction telling the agent to be careful. The agent is not asked not to edit the source spreadsheet; it is never given the ability to.
Use Read only for anything the workflow consumes but must not disturb: the master price list, the source-of-record register, a customer's submitted document. Use Read / write — the default — for the working file a step is meant to update.
Two rules follow from the file formats themselves:
Only spreadsheets, documents, and CSV can be edited in place. If you declare a File type of PDF, PowerPoint, or anything else that cannot be modified in place, the column is treated as Read only whatever the Access setting says.
A file uploaded from a local drive is a stored copy and cannot be edited in place either. To have an agent maintain a spreadsheet over time, keep it in Google Drive or OneDrive.
If the same file is reachable through two columns, one read-only and one read/write, the platform takes the cautious reading and treats it as read-only.
The Image type
Image is the type for visual content — photographs, screenshots, logos, product shots, scanned pages. An image value holds the picture's source and an optional caption, and it displays as the picture itself rather than as a link.
Use Image, not File, when a person looking at the work item should see the content. A grid of inspection photos is far more useful than a grid of file names.
Agents can look at images, not merely record them. A step can be instructed to read the label in a photo, compare a screenshot against a specification, or check that a submitted photograph shows what was asked for. Agents can also generate an image from a description, and store the result in an Image column.
Like File, an Image column can hold a single value or a list — a list is the natural shape for "site photos" or "damage evidence".
Files in content folders
The documents inside a content folder use the same machinery: each entry is a record with a name, a File value pointing at the document, and whatever additional columns you have defined for that folder. That is why a content folder can be filled from the same three sources — local upload, Google Drive, or OneDrive and SharePoint — and why folder entries can carry structured properties alongside the file.