Forum Discussion

nuwantheekshana's avatar
nuwantheekshana
Copper Contributor
Oct 04, 2026

Copilot Studio Agent Tool Not Detecting File Input from Power Automate Flow

Hi everyone,

I'm facing an issue with Copilot Studio and Power Automate Agent Flows.

I created a flow using "When an agent calls the workflow" with the following inputs:

  • RequestPayload (Text)
  • AttachmentFiles (File)

The flow saves successfully and the File input is visible in Power Automate.

However, when I add the flow as a Tool in Copilot Studio, only the text input is detected:

  • RequestPayload

     

The File input (AttachmentFiles) does not appear in the Tool Inputs section.

 

What I've tried:

- Removed and re-added the tool

- Refreshed the tool schema

- Created a brand-new V2 flow

- Changed the File input name multiple times (AttachmentFiles, UploadedFiles, FuelAttachments, etc.)

- Saved and republished the agent

- Removed and re-added the flow multiple times

The result is always the same. Only the Text input is exposed in Copilot Studio.

Additionally, if I manually try to add an input named "AttachmentFiles" in the Tool configuration, Copilot Studio returns:

"There is an error: 'DuplicateItem'"

This makes it seem like Copilot Studio recognizes the input internally, but it is not rendering or exposing it in the Tool UI.

Questions:

  1. Are File/File Collection inputs currently supported for Agent Tools in Copilot Studio?
  2. Has anyone successfully passed uploaded files from an Agent to a Power Automate flow using Tool inputs?
  3. Is this a known limitation or a bug?
  4. Is there a recommended workaround for sending PDF/JPG attachments to a flow from an Agent?

Any guidance would be greatly appreciated.

Thank you.

agent flows
copilot studio

1 Reply

  • mohitmohanmenon_93's avatar
    mohitmohanmenon_93
    Copper Contributor
    Oct 09, 2026

    Try the below:

     

    1. On the trigger, replace FuelAttachments (File) with two Text inputs- FuelAttachmentContent and FuelAttachmentName.
    2. These will then show up in the Tool’s Inputs list exactly like RequestPayload does now, since Text is clearly supported there.
    3. Map them via the Customize (pencil) option using a Power Fx formula which is pulling from the conversation’s attached file (e.g. First(System.Activity.Attachments).Content / .Name, or the relevant Topic.<var>.Content/.Name if it’s captured via a Question node first).
    4. Inside the flow, decode back to binary where needed with base64ToBinary(triggerBody()?['FuelAttachmentContent']) before handing it to whatever downstream action consumes the fuel receipt/attachment.