> For the complete documentation index, see [llms.txt](https://docs.zkbob.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.zkbob.com/roadmap/exploratory-features/xp.md).

# XP (Experience Points)

{% hint style="warning" %}
**Non-production feature**

The XP mechanism is still in research and development.
{% endhint %}

Every time you put your money in the zkBob pool you earn additional XP. XP represent your contribution to the anonymity set. The more you invest funds and the longer you hold it inside the pool, the more XP is earned.

Your XP value is updated every time you make a transaction and growth calculated using the following formula:

$$e = Acc\_{in}.b (Acc\_{out}.i - Acc\_{in}.i) + \sum\_k Note\_k.b (Acc\_{out}.i - pos(Note\_k))$$

where

* $$Acc\_{in}$$ and $$Acc\_{out}$$ is the transaction's input and output [accounts](/implementation/account-and-notes/accounts.md) respectively,
* $$Note\_k$$ is the transaction's input [note](/implementation/account-and-notes/notes.md)
* $$pos(Note\_k)$$ is the note's position in the [Merkle tree](/implementation/untitled.md)

When you make a withdrawal transaction, you can get some amount (from zero to overall) of XP. The pool contract will mint [XP ](/implementation/contracts-and-circuits/voucher-token-contract.md)for the address specified in such a transaction.


---

# 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.zkbob.com/roadmap/exploratory-features/xp.md?ask=<question>&goal=<endgoal>
```

`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.