> For the complete documentation index, see [llms.txt](https://docs.klai.studio/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.klai.studio/engineering-reference-docs/betterforms-error-pages-api/custom-error-pages.md).

# Custom error pages

All apps have a system-generated error page that you can override. To override, simply add a page with the reserved nav slug of <mark style="color:red;">`/error`</mark> and you can create and customize your own page. Error detail data is saved to the <mark style="color:red;">`app`</mark> model as <mark style="color:red;">`app.error`</mark>, and can be accessed in the error page. The error object looks like this:

```json
{
	"error": {
		"code": "404",
		"description": "Page Not Found",
		"message": "Page not found for slug: nopage"
	}
}
```


---

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