> For the complete documentation index, see [llms.txt](https://support.docstudio.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://support.docstudio.com/admin-panel/webhooks-callbacks/envelope-callbacks-overview.md).

# Envelope Callbacks Overview

An envelope callback is a feature that allows you to receive notifications at the specified URL when an envelope appears in the mailbox and matches the configured filters. You can set up callbacks for the mailbox to receive envelope notifications outside the platform. This is done via API. If the callback is configured, the callback URL is reachable, and the envelope triggers a callback, the system sends a callback to the specified URL with the following JSON data.

{% hint style="info" %}
See the [Glossary](/glossary/glossary.md) for DocStudio term definitions.
{% endhint %}

**JSON Callback data**

```json
{
  "mailbox": "F32A3BD9-CE5B-4AC5-A2D7-C2A2E7DD6636",
  "uuid": "74acfb70-78e9-4ca5-ac73-054c72402c0a",
  "label": ["string"],
  "status": "string",
  "subject": "string",
  "receiveDate": 1676039226765,
  "expireDate": 1678631226504,
  "template": "ebeb302b-597e-4b47-9de2-5ad3a33e4385",
  "sender": "fdfde267-6558-40a9-93fd-e59529baef36"
}
```

**Description of the JSON data**

<table><thead><tr><th width="136">mailbox</th><th>Mailbox UUID of the mailbox that is currently processing the envelope</th></tr></thead><tbody><tr><td>uuid</td><td>Envelope UUID that triggered the callback on the platform</td></tr><tr><td>label</td><td>List of label UUIDs assigned to a particular envelope</td></tr><tr><td>status</td><td>Status of the envelope. The most expected statuses are WAITING, COMPLETED, EXPIRED, CANCELLED</td></tr><tr><td>subject</td><td>Envelope subject</td></tr><tr><td>receiveDate</td><td>Envelope receiving date. Returned in UNIX time</td></tr><tr><td>expireDate</td><td>Envelope expiration date. Returned in UNIX time</td></tr><tr><td>template</td><td>UUID of the template from which the envelope was created</td></tr><tr><td>sender</td><td>Envelope sender UUID of the mailbox that initiated the envelope processing flow</td></tr></tbody></table>