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

# Add Attachment

> Attach a public URL to a Trello card.

**Add Attachment** adds a URL attachment to a Trello card and can use it as the
card cover.

## Inputs

| Input                   | Type           | Required | Description                                   |
| ----------------------- | -------------- | -------- | --------------------------------------------- |
| **Third-party account** | Trello account | Yes      | An account with write access to the card.     |
| **Card ID or URL**      | String         | Yes      | A card ID, short link, or complete card URL.  |
| **Attachment URL**      | URL            | Yes      | The public URL to attach.                     |
| **Name**                | String         | No       | An optional attachment display name.          |
| **Set Cover**           | Boolean        | No       | Use the attachment as the cover. Default off. |

## Outputs

| Output            | Type   | Description                                 |
| ----------------- | ------ | ------------------------------------------- |
| **Attachment**    | Object | The created attachment's normalized fields. |
| **Attachment ID** | String | Trello's identifier for the attachment.     |

**Attachment** exposes **ID**, **Name**, **URL**, **Bytes**, **Added At**,
**MIME Type**, **Is Upload**, and **Position**. Some metadata may be empty for
URL attachments.