> For clean Markdown of any page, append .md to the page URL.
> For a complete documentation index, see https://docs.getunleash.io/api/register-frontend-client/llms.txt.
> For AI client integration (Claude Code, Cursor, etc.), connect to the MCP server at https://docs.getunleash.io/_mcp/server.

# Register a client SDK

POST https://app.unleash-instance.example.com/api/frontend/client/register
Content-Type: application/json

This is for future use. Currently Frontend client registration is not supported. Returning 200 for clients that expect this status code. If the Frontend API is disabled 404 is returned.

Reference: https://docs.getunleash.io/api/register-frontend-client

## Authentication

- `Authorization` header (required) — API key needed to access this API
- `Authorization` header (bearer token, required) — API key needed to access this API, in Bearer token format

## Request

### Body (application/json)

This endpoint expects a frontendApiClientSchema.

- `appName` (string, required) — Name of the application using Unleash
- `interval` (double, required) — At which interval, in milliseconds, will this client be expected to send metrics
- `started` (FrontendApiClientSchemaStarted, required) — When this client started. Should be reported as ISO8601 time.
- `strategies` (list of string, required) — List of strategies implemented by this application
- `instanceId` (string, optional) — Instance id for this application (typically hostname, podId or similar)
- `sdkVersion` (string, optional) — Optional field that describes the sdk version (name:version)
- `environment` (string, optional, deprecated) — deprecated

## Response

### 200

This response has no body.

## Errors

### 400 Bad Request Error

The request data does not match what we expect.

- `id` (string, optional) — The ID of the error instance
- `name` (string, optional) — The name of the error kind
- `message` (string, optional) — A description of what went wrong.

### 401 Unauthorized Error

Authorization information is missing or invalid. Provide a valid API token as the `authorization` header, e.g. `authorization:*.*.my-admin-token`.

- `id` (string, optional) — The ID of the error instance
- `name` (string, optional) — The name of the error kind
- `message` (string, optional) — A description of what went wrong.

### 404 Not Found Error

The requested resource was not found.

- `id` (string, optional) — The ID of the error instance
- `name` (string, optional) — The name of the error kind
- `message` (string, optional) — A description of what went wrong.

## Types

### FrontendApiClientSchemaStarted

When this client started. Should be reported as ISO8601 time.

## Examples

**Request**

```json
{
  "appName": "string",
  "interval": 1.1,
  "started": "2024-01-15T09:30:00Z",
  "strategies": [
    "string"
  ]
}
```

**Response**

```json
{}
```

**SDK Code**

```python
import requests

url = "https://app.unleash-instance.example.com/api/frontend/client/register"

payload = {
    "appName": "string",
    "interval": 1.1,
    "started": "2024-01-15T09:30:00Z",
    "strategies": ["string"]
}
headers = {
    "Authorization": "<apiKey>",
    "Content-Type": "application/json"
}

response = requests.post(url, json=payload, headers=headers)

print(response.json())
```

```javascript
const url = 'https://app.unleash-instance.example.com/api/frontend/client/register';
const options = {
  method: 'POST',
  headers: {Authorization: '<apiKey>', 'Content-Type': 'application/json'},
  body: '{"appName":"string","interval":1.1,"started":"2024-01-15T09:30:00Z","strategies":["string"]}'
};

try {
  const response = await fetch(url, options);
  const data = await response.json();
  console.log(data);
} catch (error) {
  console.error(error);
}
```

```go
package main

import (
	"fmt"
	"strings"
	"net/http"
	"io"
)

func main() {

	url := "https://app.unleash-instance.example.com/api/frontend/client/register"

	payload := strings.NewReader("{\n  \"appName\": \"string\",\n  \"interval\": 1.1,\n  \"started\": \"2024-01-15T09:30:00Z\",\n  \"strategies\": [\n    \"string\"\n  ]\n}")

	req, _ := http.NewRequest("POST", url, payload)

	req.Header.Add("Authorization", "<apiKey>")
	req.Header.Add("Content-Type", "application/json")

	res, _ := http.DefaultClient.Do(req)

	defer res.Body.Close()
	body, _ := io.ReadAll(res.Body)

	fmt.Println(res)
	fmt.Println(string(body))

}
```

```ruby
require 'uri'
require 'net/http'

url = URI("https://app.unleash-instance.example.com/api/frontend/client/register")

http = Net::HTTP.new(url.host, url.port)
http.use_ssl = true

request = Net::HTTP::Post.new(url)
request["Authorization"] = '<apiKey>'
request["Content-Type"] = 'application/json'
request.body = "{\n  \"appName\": \"string\",\n  \"interval\": 1.1,\n  \"started\": \"2024-01-15T09:30:00Z\",\n  \"strategies\": [\n    \"string\"\n  ]\n}"

response = http.request(request)
puts response.read_body
```

```java
import com.mashape.unirest.http.HttpResponse;
import com.mashape.unirest.http.Unirest;

HttpResponse<String> response = Unirest.post("https://app.unleash-instance.example.com/api/frontend/client/register")
  .header("Authorization", "<apiKey>")
  .header("Content-Type", "application/json")
  .body("{\n  \"appName\": \"string\",\n  \"interval\": 1.1,\n  \"started\": \"2024-01-15T09:30:00Z\",\n  \"strategies\": [\n    \"string\"\n  ]\n}")
  .asString();
```

```php
<?php
require_once('vendor/autoload.php');

$client = new \GuzzleHttp\Client();

$response = $client->request('POST', 'https://app.unleash-instance.example.com/api/frontend/client/register', [
  'body' => '{
  "appName": "string",
  "interval": 1.1,
  "started": "2024-01-15T09:30:00Z",
  "strategies": [
    "string"
  ]
}',
  'headers' => [
    'Authorization' => '<apiKey>',
    'Content-Type' => 'application/json',
  ],
]);

echo $response->getBody();
```

```csharp
using RestSharp;

var client = new RestClient("https://app.unleash-instance.example.com/api/frontend/client/register");
var request = new RestRequest(Method.POST);
request.AddHeader("Authorization", "<apiKey>");
request.AddHeader("Content-Type", "application/json");
request.AddParameter("application/json", "{\n  \"appName\": \"string\",\n  \"interval\": 1.1,\n  \"started\": \"2024-01-15T09:30:00Z\",\n  \"strategies\": [\n    \"string\"\n  ]\n}", ParameterType.RequestBody);
IRestResponse response = client.Execute(request);
```

```swift
import Foundation

let headers = [
  "Authorization": "<apiKey>",
  "Content-Type": "application/json"
]
let parameters = [
  "appName": "string",
  "interval": 1.1,
  "started": "2024-01-15T09:30:00Z",
  "strategies": ["string"]
] as [String : Any]

let postData = JSONSerialization.data(withJSONObject: parameters, options: [])

let request = NSMutableURLRequest(url: NSURL(string: "https://app.unleash-instance.example.com/api/frontend/client/register")! as URL,
                                        cachePolicy: .useProtocolCachePolicy,
                                    timeoutInterval: 10.0)
request.httpMethod = "POST"
request.allHTTPHeaderFields = headers
request.httpBody = postData as Data

let session = URLSession.shared
let dataTask = session.dataTask(with: request as URLRequest, completionHandler: { (data, response, error) -> Void in
  if (error != nil) {
    print(error as Any)
  } else {
    let httpResponse = response as? HTTPURLResponse
    print(httpResponse)
  }
})

dataTask.resume()
```