> For the complete documentation index, see [llms.txt](https://api-documentation.autoshares.dev/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://api-documentation.autoshares.dev/rest-api/trading-api/watchlists/add-security-to-watchlist-by-id/watchlists_addsecuritybyid.md).

# Syntax

## Add security by Id.

```
PUT /v{version}/users/{userId}/watchlists/{watchlistId}/securities/{securityId}
```

### Description

This API endpoint enables you add a security to a custom watchlist by providing the security’s internal identifier in the request header.

### Parameters

| Type       | Name                           | Description                                                                                                                                 | Schema          | Default |
| ---------- | ------------------------------ | ------------------------------------------------------------------------------------------------------------------------------------------- | --------------- | ------- |
| **Header** | **Authorization**   *required* | This is the authorization token that you retrieved from the first endpoint (/token).                                                        | string          |         |
| **Header** | **Et-App-Key**   *required*    | This is your app’s unique key that can be retrieved from the BO Companies widget in Autoshares Trader.                                      | string          |         |
| **Path**   | **securityId**   *required*    | This is the internal identifier of the security that needs to be added to the specified watchlist.                                          | integer (int32) |         |
| **Path**   | **userId**   *required*        | This is the internal identifier of the user whose watchlist needs to be modified.                                                           | integer (int32) |         |
| **Path**   | **version**   *required*       | This is the version of the API. Unless you have multiple versions of Autoshares Trader’s API deployed in your environment, leave it at 1.0. | string          | `"1"`   |
| **Path**   | **watchlistId**   *required*   | This is the internal identifier of the watchlist that needs to be appended by a new security.                                               | integer (int32) |         |

### Responses

| HTTP Code | Description                                                                                       | Schema                                                                                                                          |
| --------- | ------------------------------------------------------------------------------------------------- | ------------------------------------------------------------------------------------------------------------------------------- |
| **200**   | Successful request, JSON data containing the modified watchlist is returned.                      | [WatchlistModel](/rest-api/trading-api/watchlists/add-security-to-watchlist-by-id/watchlists_addsecuritybyid.md#watchlistmodel) |
| **401**   | The access level of the provided authorization token is not sufficient to perform this operation. | No Content                                                                                                                      |
| **403**   | The provided Et-App-Key is incorrect.                                                             | No Content                                                                                                                      |
| **409**   | The watchlist couldn’t be modified due to some conflict (perhaps the watchlist is read-only       | No Content                                                                                                                      |
| **422**   | A validation error occurred while processing the request.                                         | No Content                                                                                                                      |
| **500**   | Internal server error                                                                             | No Content                                                                                                                      |

### Produces

* `application/json`
* `text/json`