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

# Add Feature

> This method will set a certain feature (F1..F8) to true. If the key algorithm in the product is SKGL, the key string will be changed if necessary. Otherwise,...

This method will set a certain feature (F1..F8) to **true**. If the
[key algorithm](https://help.cryptolens.io/web-interface/skgl-vs-skm15) in the product
is SKGL, the key string will be changed if necessary. Otherwise, if SKM15 is used, the key will stay the same. To do the reverse,
please see [RemoveFeature](/api-reference/generated/RemoveFeature).

This method is accessed by [https://api.cryptolens.io/api/key/AddFeature](https://api.cryptolens.io/api/key/AddFeature)

### Parameters

| **Parameter** | **Description** | **Remarks** |
| - | - | - |
| ProductId | the product id (=\*\*\[ProductId] \*\*) | required |
| Key | the serial key string | required |
| Feature | The feature number, 1 to 8 (inclusive), that should be set to true. | required |
| v | Method version. | optional. by default, it's 1. |

### Results

| **Parameter** | **Description** | **Remarks** |
| - | - | - |
| Result | This is either **0**(=success) or **1**(=error). | always returned |
| Message | The message that provides additional information about the result. If it's a successful result, either **null** or the **new key** (if using SKGL) will be returned. Otherwise, in case of an error, a short message will be returned describing the error. | always returned. |

### Example results

```text theme={null}
{"result":0,"message":""}
```

### Errors

| **Error** |
| - |
| Access denied. |
| The input parameters were incorrect. |
| Could not find the product. |
| Could not find the key. |