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

# Transaction Notes API

> Add custom remarks to a completed transaction. Remarks will show in the Merchant Portal.

<Note>
  This endpoint is only available to merchants who **do not** pass in the `mchid`.
</Note>

Merchants can use this API to attach remarks to a completed transaction. These remarks will be visible in the Merchant Portal and transaction reports.

***

## API Endpoint

**URL**: `/trade/v1/add_note`\
**Method**: `POST`\
**Content-Type**: `application/x-www-form-urlencoded`

***

## Request Parameters

| Attribute | Mandatory | Type        | Description                                          |
| --------- | --------- | ----------- | ---------------------------------------------------- |
| `code`    | Yes       | String(32)  | Merchant app code provided by QFPay                  |
| `syssn`   | Yes       | String(40)  | QFPay transaction number (from original transaction) |
| `note`    | Yes       | String(200) | Remark content to be added (max 200 characters)      |

***

## Request Sample

```http theme={null}
POST /trade/v1/add_note
Content-Type: application/x-www-form-urlencoded
X-QF-APPCODE: D5589D2A1F2E42A9A60C37**********
X-QF-SIGN: 6FB43AC29175B4602FF95F8332028F19

code=A6A49A6******DFE94EA95032&note=add_note&syssn=20190722000200020081075691
```

## Response Parameters

| Attribute    | Type        | Description                                      |
| ------------ | ----------- | ------------------------------------------------ |
| `resperr`    | String(128) | Transaction result message                       |
| `respmsg`    | String(128) | Error message                                    |
| `respcd`     | String(4)   | Return code (`0000` = Interface call successful) |
| `data.syssn` | String(40)  | QFPay transaction number                         |

## Response Sample

```json theme={null}
{
  "resperr": "Success",
  "respcd": "0000",
  "respmsg": "",
  "data": {
    "syssn": "20190722000200020081084545"
  }
}
```