> For the complete documentation index, see [llms.txt](https://docs.fastn.ai/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.fastn.ai/tutorials-1/flow-customization-and-operations/how-to-customize-your-error-notification-flow.md).

# How to Customize Your Error Notification Flow?

When a flow fails, Fastn can automatically forward errors to a **notification flow**. By default, this is `fastnErrorNotification`. You can customize it to format error messages, enrich them with extra context, or forward alerts to external systems.

* In your flow, go to the **right-hand sidebar → Settings → Configuration**.

<figure><img src="/files/FCoi6t4DJBrydfE2T5bY" alt=""><figcaption></figcaption></figure>

<figure><img src="/files/vAFhGKqpkheOGrF6SUrs" alt=""><figcaption></figcaption></figure>

* Under **Error Notification**, toggle **Enable Error Notification**.

<figure><img src="/files/vLTPGTDF4shAKYE1EiIS" alt=""><figcaption></figcaption></figure>

* Open the **fastnErrorNotification** flow.

<figure><img src="/files/NlnsuaTzaHuilci4GeqO" alt=""><figcaption></figcaption></figure>

* This flow starts with an **On API Request** trigger.
* Inside this flow, you can:
  * Map values from the incoming error.
  * Alter the error message.
  * Optionally, add any other steps as needed.

<figure><img src="/files/7Hn8HUVCqH6NYKFlcUbg" alt=""><figcaption></figcaption></figure>

* Save your changes.

**With this setup, you have control over how error messages are handled and displayed for your flow.**


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