> For the complete documentation index, see [llms.txt](https://docs.heisenware.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.heisenware.com/app-builder/build-backend/error-handler.md).
# Error handler
The Error Handler allows you to gracefully manage potential errors thrown by a Function. It provides a separate output that will only activate if the Function it's attached to fails or throws an exception.
This enables you to build a safe, separate logic path to handle error conditions, such as logging the error details to a database or displaying a user-friendly error message on the UI.
Error simulator Function with captured error message and JSONata modification.
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