> For the complete documentation index, see [llms.txt](https://developer.perculus.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://developer.perculus.com/v2-en/services/attendee-management/creating-and-updating-attendees/upsert-by-email-guests.md).

# Upsert by Email (Guests)

{% hint style="warning" %}
Adding an attendee as a guest, with email, will deprive you from <mark style="color:red;">some</mark> functionalities as opposed to adding an existing user to a session as a participant.
{% endhint %}

External participants are attendees of a session that doesn't belong to an account. Below, you can see the parameters which you can send:

<table><thead><tr><th>Parameter</th><th width="161">Type</th><th width="158">Required</th><th>Default</th><th>Description</th></tr></thead><tbody><tr><td>name</td><td>string</td><td>Yes</td><td>n/a</td><td>Name of the participant</td></tr><tr><td>surname</td><td>string</td><td>Yes</td><td>n/a</td><td>Surname of the participant</td></tr><tr><td>email</td><td>string</td><td>Yes</td><td>n/a</td><td>Email address of the participant</td></tr><tr><td>mobile</td><td>string</td><td>No</td><td>null</td><td>Mobile of the participant</td></tr><tr><td>role</td><td>string</td><td>No</td><td>u</td><td>Role of the participant(<a href="/pages/UTVEaKGzw0Q9EmCFXDq1">see</a>)</td></tr></tbody></table>