> For the complete documentation index, see [llms.txt](https://docs.appfarm.io/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.appfarm.io/library/action-nodes/throw-exception.md).
# Throw exception
The Throw Exception action node is used to throw custom exceptions when running an action. [Catch Exception](/library/action-nodes/catch-exception.md) can catch and handle these custom exceptions to facilitate accurate and effective error handling.
### Usage
There are several valuable use cases for the Throw Exception action node:
* **Data validation:** When handling invalid data from form submissions or data received from external endpoints.
* **Improved error messages:** When an error occurs, throwing a custom exception allows you to deliver the user clear and actionable error messages.
* **Improved logging and debugging:** For logging and debugging, throwing a custom exception can provide more specific and detailed information. This is especially useful with an [event log setup](/how-to/logic-and-flow/event-log-design.md).
### Properties
Property
Description
Message
Description of the thrown error.
Custom Code
Throw a custom error code to catch this specific error with a Catch Exception action node.
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