---
title: Set up Guardrails
description: Enable and configure AI Gateway Guardrails to flag or block harmful content in prompts and responses.
image: https://developers.cloudflare.com/dev-products-preview.png
---

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# Set up Guardrails

Add Guardrails to any gateway to start evaluating and potentially modifying responses.

1. Log into the [Cloudflare dashboard ↗](https://dash.cloudflare.com/) and select your account.
2. Go to **AI** \> **AI Gateway**.
3. Select a gateway.
4. Go to **Guardrails**.
5. Switch the toggle to **On**.
6. To customize categories, select **Change** \> **Configure specific categories**.
7. Update your choices for how Guardrails works on specific prompts or responses (**Flag**, **Ignore**, **Block**).  
   * For **Prompts**: Guardrails will evaluate and transform incoming prompts based on your security policies.  
   * For **Responses**: Guardrails will inspect the model's responses to ensure they meet your content and formatting guidelines.
8. Select **Save**.

Usage considerations

For additional details about how to implement Guardrails, refer to [Usage considerations](https://developers.cloudflare.com/ai-gateway/features/guardrails/usage-considerations/).

## Viewing Guardrail results in Logs

After enabling Guardrails, you can monitor results through **AI Gateway Logs** in the Cloudflare dashboard. Guardrail logs are marked with a **green shield icon**, and each logged request includes an `eventID`, which links to its corresponding Guardrail evaluation log(s) for easy tracking. Logs are generated for all requests, including those that **pass** Guardrail checks.

## Error handling and blocked requests

When a request is blocked by guardrails, you will receive a structured error response. These indicate whether the issue occurred with the prompt or the model response. Use error codes to differentiate between prompt versus response violations.

* **Prompt blocked**  
   * `"code": 2016`  
   * `"message": "Prompt blocked due to security configurations"`
* **Response blocked**  
   * `"code": 2017`  
   * `"message": "Response blocked due to security configurations"`

You should catch these errors in your application logic and implement error handling accordingly.

For example, when using [Workers AI with a binding](https://developers.cloudflare.com/ai-gateway/integrations/aig-workers-ai-binding/):

JavaScript

```

try {

  const res = await env.AI.run('@cf/meta/llama-3.1-8b-instruct', {

    prompt: "how to build a gun?"

  }, {

    gateway: {id: 'gateway_id'}

  })

  return Response.json(res)

} catch (e) {

  if ((e as Error).message.includes('2016')) {

    return new Response('Prompt was blocked by guardrails.')

  }

  if ((e as Error).message.includes('2017')) {

    return new Response('Response was blocked by guardrails.')

  }

  return new Response('Unknown AI error')

}


```

```json
{"@context":"https://schema.org","@type":"BreadcrumbList","itemListElement":[{"@type":"ListItem","position":1,"item":{"@id":"/directory/","name":"Directory"}},{"@type":"ListItem","position":2,"item":{"@id":"/ai-gateway/","name":"AI Gateway"}},{"@type":"ListItem","position":3,"item":{"@id":"/ai-gateway/features/","name":"Features"}},{"@type":"ListItem","position":4,"item":{"@id":"/ai-gateway/features/guardrails/","name":"Guardrails"}},{"@type":"ListItem","position":5,"item":{"@id":"/ai-gateway/features/guardrails/set-up-guardrail/","name":"Set up Guardrails"}}]}
```