[2025 Update] Save Files from Copilot Studio to SharePoint (Standard Feature Guide)

This is a quick note on how to retrieve the content of files attached to a conversation.

Goal

I want to build an agent that saves a file to a SharePoint Online (SPO) document library when I attach a file in the conversation and ask it to “save file.”

Build

First, create a new topic and set the trigger to activate when “asked to save a file.”

Next, select [Add a tool] > [Connector], and choose SharePoint [Create file].

Click [Submit].

*As you can see, the popup might not disappear and could block the view, so you may need to maneuver around it to click the button.

In the input fields for the added tool, set the “Site Address” and “Folder Path” to your destination.
Then, enter the following formula for [File Name]:

First(System.Activity.Attachments).Name

Enter the following formula for [File Content]:

First(System.Activity.Attachments).Content

The build is now complete.

Test

When you ask the agent to save an attached file:

It will ask for connection approval. Click [Allow].
The flow might error out the first time—don’t worry about it. Just restart the conversation via [Start a new test session].

Make the same request again. This time the flow succeeds:

And the file is saved in the document library.

This is significantly easier compared to the “legacy method” described below.

Since this was just a test, the manual connection approval was fine. However, in actual operation, you may need to implement measures such as configuring SSO correctly or adding a topic at the beginning of the conversation to request authentication proactively to prevent errors.

Related Articles

[How to create a Multimodal Agent]

[Copilot Studio FX Guide]

[Power Automate Actions in Copilot Studio]

Bonus: [Legacy Method Archive] ChannelData & Power Automate

Goal

This section discusses how to retrieve a file attached in a Copilot conversation and use it in subsequent nodes or Power Automate (Legacy approach).

Attachments are available in ChannelData

There is an “Attachments” property in System.Activity, which is misleading.
According to the reference below, attachment information actually exists in “ChannelData.”


Reference Link

When we inspect ChannelData, we can see that the file data (Base64) is contained in the OriginalAttachments property.

We will use this Base64 data to add file saving functionality to the agent.

Build: Saving attached files to SharePoint (Legacy)

In this example, we assume we are targeting only the first attached file.

*If you want to handle multiple files, do not use the First function; instead, handle them as a Table or loop with Foreach.

Build Power Automate

First, build the Power Automate flow to save the file.

Retrieve the file name and data string as arguments, then use the “Create file” action to save it.
Ensure the data string is converted to binary using the base64ToBinary function.

*Since “File” type arguments were not yet supported for Copilot Studio calls at the time, we create the argument as a “String.”

Power Automate construction is complete.

Build Copilot Studio (Legacy)

Create a topic and retrieve the contentUrl of the first file in ChannelData as a string:

Use a combination of Split and Index to extract the data string portion from the contentUrl:

Then retrieve the file name:

Pass these values to the Power Automate flow created earlier:

The legacy build is complete.

// Get contentUrl
Text(First(System.Activity.ChannelData.OriginalAttachments).contentUrl)

// Get data portion
Index(Split(Topic.contentUrl,","),2).Value

// Get file name
Text(First(System.Activity.ChannelData.OriginalAttachments).name)

Legacy Test

When you send a file and trigger the topic, file info is passed to Power Automate:

And the file is successfully saved.