> For the complete documentation index, see [llms.txt](https://docs.mellow.finance/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.mellow.finance/core-vaults/architecture/hooks/basicredeemhook.md).

# BasicRedeemHook

### Overview

`BasicRedeemHook` is a minimal hook implementation for `IHook`, designed to dynamically fetch liquidity from subvaults during redemption processing in a `VaultModule`. It ensures that enough assets are available for user redemptions by pulling liquidity from a set of registered subvaults.

This hook is typically invoked by a vault’s redemption queue or during `redeem()` operations when assets must be made liquid.

### Purpose

* Ensures **sufficient liquidity** in the vault to fulfill asset redemptions.
* Minimizes idle capital by **pulling only when needed**.
* Supports **liquidity routing** across subvaults.

### Key Functions

### `callHook(address asset, uint256 assets)`

Attempts to make `assets` of `asset` liquid within the main vault by pulling from subvaults if needed.

**Execution Flow:**

1. Checks how much of the `asset` the vault already holds.
2. If balance is sufficient → no-op.
3. Otherwise:
   * Iterates over subvaults (via `subvaultAt(i)`)
   * For each subvault:
     * Pulls **only the required portion** via `hookPullAssets()`
     * Stops when total required assets have been pulled

**Guarantees:**

* Only pulls the **exact missing amount**, no over-pulling
* Efficient: stops once liquidity need is satisfied
* Skips subvaults with `0` balance

### `getLiquidAssets(address asset) → uint256`

Returns the **total liquid amount of a given asset** available across the vault and all its subvaults.

* Reads balances:
  * `vault.balanceOf(asset)`
  * `subvault[i].balanceOf(asset)` for each subvault
* Aggregates and returns sum

### Contract Assumptions

* The `vault` invoking this hook implements `IVaultModule` and supports:
  * `subvaults()` → total number of subvaults
  * `subvaultAt(index)` → address of a given subvault
  * `hookPullAssets(subvault, asset, amount)` → callable method to move funds

### Security Considerations

* Hook only pulls assets using vault-controlled `hookPullAssets()`, ensuring controlled asset flow.
* Assumes vault validates which hook is active — no permissioning within the hook itself.


---

# 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.mellow.finance/core-vaults/architecture/hooks/basicredeemhook.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.