# Build Approval Transaction

This API returns the transaction data so you get to decide whether to approve yBridge to spend your tokens.

## Get the approve transaction

<mark style="color:blue;">`GET`</mark> `endpoint/approve`

#### Query Parameters

| Name                                           | Type   | Description                                                |
| ---------------------------------------------- | ------ | ---------------------------------------------------------- |
| chainId<mark style="color:red;">\*</mark>      | String | chain ID                                                   |
| spender<mark style="color:red;">\*</mark>      | String | Address of the spender                                     |
| tokenAddress<mark style="color:red;">\*</mark> | String | Token address                                              |
| amount                                         | String | Amount of tokens to be approved. If not given, approve max |

{% tabs %}
{% tab title="200: OK Success" %}

```javascript
{
    "isSuccess": true,
    "msg": "",
    "tokenAddress": "<tokenAddress>",
    "spender": "<spender>",
    "amount": "<amount>",
    "tx": {
        "to": "<tokenAddress>",
        "data": "<data>",
    }
}
```

{% endtab %}
{% endtabs %}

{% hint style="info" %}
**`NOTE :`**` ``The spender should be the contractAddress in the response of` [`Get Quote`](https://app.gitbook.com/s/-Mcs9EhDrgbKHodtcAT6/~/changes/HTPvqHWDmiwzKo005mtN/xswap-api/v1/get-quote)`.`
{% endhint %}

{% hint style="warning" %}
&#x200B;**`IMPORTANT :`**` ``Note that the amount parameter should be padded with zeroes. For example, pass`` `**`100000000`**` ``instead of`` `**`100`**` ``if the decimal digits of the token are 6.`
{% endhint %}


---

# Agent Instructions: Querying This Documentation

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Perform an HTTP GET request on the current page URL with the `ask` query parameter:

```
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```

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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.