> For the complete documentation index, see [llms.txt](https://docs.photoroom.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.photoroom.com/remove-background-api-basic-plan/uncertainty-score.md).
# Uncertainty score
The API returns a confidence score of the cutout through the HTTP header `x-uncertainty-score`.
The uncertainty score is a number between `0` and `1`:
* `0` means the model is very confident that the cutout is accurate
* `1` means the model is unsure.
For instance, shoes on a shoe box might give a higher uncertainty score as the model is unsure what to segment (shoes, box or both):
High uncertainty score: between 0.6 and 1
Low uncertainty score: between 0 and 0.3
{% hint style="warning" %}
Please note that the uncertainty score is not guaranteed to be stable over time: the same image might yield a different uncertainty score in the future.
{% endhint %}
In some cases, we might not be able to able to return an uncertainty score (e.g. if an image contains humans), in that case the value `-1` will be returned.
{% hint style="info" %}
Learn more about all the important features to look for in AI image background removal technology in [this article](https://www.photoroom.com/blog/image-background-removal-technology-comparison).
{% endhint %}
---
# Agent Instructions
This documentation is published with GitBook. GitBook is the documentation platform designed so that both humans and AI agents can read, navigate, and reason over technical content effectively. Learn more at gitbook.com.
## Querying This Documentation
If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question.
Perform an HTTP GET request on the current page URL with the `ask` query parameter, and the optional `goal` query parameter:
```
GET https://docs.photoroom.com/remove-background-api-basic-plan/uncertainty-score.md?ask=&goal=
```
`ask` is the immediate question: it should be specific, self-contained, and written in natural language.
`goal` is optional and describes the broader end goal you are ultimately trying to accomplish on behalf of the user. GitBook uses it to tailor the answer towards what is most useful for that goal.
The response will contain a direct answer to the question and relevant excerpts and sources from the documentation.
Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.