> ## Documentation Index
> Fetch the complete documentation index at: https://docs.goguardian.com/llms.txt
> Use this file to discover all available pages before exploring further.
# Block Proxy Sites with Smart Alerts
> Create a Smart Alert Trigger that uses the Proxy category to automatically detect and block proxy sites, including org unit scoping and confidence levels.
The Smart Alerts algorithm can scan for and detect websites with proxy elements using the **Proxy** category, and generate Smart Alerts to block them.
## Understand Proxies
A web proxy is an intermediary service between a user and the internet. Because the URL stays the same as the proxy's URL regardless of what is accessed, sites that would otherwise be blocked by URL or category can still be reachable through a proxy.
## Create a Trigger to Block Proxies
On the [Smart Alerts page](https://admin.goguardian.com/smart-alerts), open the **Triggers** tab and click **Create New Trigger**.
1. Go to **Triggers** in GoGuardian Admin.
2. Click **Add New Trigger**.
3. Enter a name for the Trigger — GoGuardian recommends naming it for who it applies to. Then choose which **Org Units** to apply it to. The Trigger's actions only run for students in the selected OUs. For example, a Trigger set to the 6th Grade OU acts only on 6th Grade students, while one set to the top-level OU covers all students.
OU coverage cascades to child OUs. A Trigger applied to a parent OU (such as "Middle School") also covers all child OUs beneath it, such as 6th Grade, 7th Grade, and 8th Grade. To apply a Trigger to all users in your organization, select the root OU, displayed as "/".
4. Set the **Category** to **Proxy**.
5. Choose the confidence threshold for the Trigger — a measure of how confident the algorithm is that the alert is correctly categorized:
| Level | Threshold | When to use |
| --------- | --------- | ------------------------------------------------------------------------ |
| Medium | 50% | Applies to all Smart Alerts; higher chance of inaccurate classifications |
| High | 70% | More likely to classify alerts accurately |
| Very High | 90% | Applies only to alerts that are very likely to be accurate |
If your Trigger is producing too many responses to inaccurate alerts, increase the confidence level. For Proxy triggers, start at Medium confidence and raise the threshold if false positives are common.
6. Select one or more Actions to fire when a Smart Alert meets the Trigger conditions. Actions can be combined in any configuration. See [Understand Trigger Actions](/products/admin/configure-smart-alert-triggers#understand-trigger-actions) for a description of each option.
7. Click **Save** to activate the Trigger.
8. The new Trigger appears in your Triggers list with its assigned OUs, category, and confidence level. Confirm that the correct OUs and confidence level are displayed. The Trigger is now active and will fire its Actions when a matching Smart Alert is generated.
