> ## Documentation Index
> Fetch the complete documentation index at: https://custodydocs-en.chainup.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Overview

API Co-Signer helps users automate approval and signing processes, making it ideal for workspaces with high transaction volumes or frequent activities. If you’re looking to automate transactions, it’s the perfect solution.

* Before signing a transaction, Co-Signer will callback to your business system. It can initiate the signature only after authorization is obtained; otherwise, the transaction cannot proceed.

* After the app-side signature authorization for the consolidation transaction, it will not callback to the Client system.

* [View Co-Signer Deployment Documentation](https://custodydocs-en.chainup.com/api-references/mpc-apis/co-signer/deploy.md)

## Creating an Address

![](https://mintcdn.com/zhp-9d4bf690/AEZfbc6Vzsw1ahFp/images/apis/mpc-create-address_en.png?fit=max\&auto=format\&n=AEZfbc6Vzsw1ahFp\&q=85\&s=365a112633d29bc56d88c3e7a899b3d8)

## Automatic Signature (Callback Method)

![](https://mintcdn.com/zhp-9d4bf690/AEZfbc6Vzsw1ahFp/images/apis/mpc-withdraw-callback_en.png?fit=max\&auto=format\&n=AEZfbc6Vzsw1ahFp\&q=85\&s=870ff345f6f15f4232713b2c47d4dab5)

## Automatic Signature (Signature Sign Verification Method)

![](https://mintcdn.com/zhp-9d4bf690/AEZfbc6Vzsw1ahFp/images/apis/mpc-withdraw-sign_en.png?fit=max\&auto=format\&n=AEZfbc6Vzsw1ahFp\&q=85\&s=64d1b5447f3e5e6573034fe437433844)

> [!TIP]
>
> Both callback and signature sign verification methods can coexist, but **at least one verification method is required**. Developers can choose the verification method according to their needs.


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