> For clean Markdown of any page, append .md to the page URL.
> For a complete documentation index, see https://docs.ouster.com/sensor-docs/firmware/3.2/api-reference/ouster-http-api/authentication/post-auth-login/llms.txt.
> For AI client integration (Claude Code, Cursor, etc.), connect to the MCP server at https://docs.ouster.com/_mcp/server.

# Validate JWT and issue session token

POST http://os-992244000006.local/api/v1/auth/login
Content-Type: application/json

Validates JWT from auth server and issues session token.

**JWT Validation (security-critical order):**
1. Signature verification (ECDSA P-256)
2. Audience check (must match device serial number)
3. POH expiration check (`exp_poh` vs current POH)
4. Nonce validation (single-use, must be pending)

**Token Usage Types:**
- `cookie`: Sets HTTP-only cookie, returns success message
- `bearer`: Returns session token in body, no cookie set

**Security Properties:**
- All validation failures return HTTP 401 with no information leakage
- Nonce marked as used after successful validation
- Session tokens expire based on POH, not wall-clock time
- Cookie security: `http_only=True`, `same_site='Strict'`, `secure=True` (HTTPS)


Reference: https://docs.ouster.com/sensor-docs/firmware/api-reference/ouster-http-api/authentication/post-auth-login

## Request

### Body (application/json)

This endpoint expects a LoginRequest.

- `token` (string, required) — JWT signed by auth server (ECDSA P-256)
- `token_usage` (enum, required) — Token usage type: - `cookie`: Session token delivered via HTTP-only cookie (browser clients) - `bearer`: Session token delivered via Authorization Bearer header (API clients)
  - Allowed values: `cookie`, `bearer`

## Response

### 200

Login successful (bearer token mode)

- `token` (string, required) — Session token for bearer authentication (base64url, 22 chars)

## Errors

### 400 Bad Request Error

Invalid request (missing/malformed fields)

- `title` (string, optional) — Error title
- `description` (string, optional) — Error description

### 401 Unauthorized Error

JWT validation failed (no distinguishing details): - Invalid signature - Wrong audience (device serial number) - Expired POH - Invalid/expired/reused nonce - Malformed JWT

- `title` (string, optional) — Error title
- `description` (string, optional) — Error description

## Examples

**Request**

```json
{
  "token": "eyJhbGciOiJFUzI1NiIsInR5cCI6IkpXVCJ9...",
  "token_usage": "cookie"
}
```

**Response**

```json
{
  "token": "x1y2z3a4b5c6d7e8f9g0h1"
}
```

**SDK Code**

```python Authentication_postAuthLogin_example
import requests

url = "http://os-992244000006.local/api/v1/auth/login"

payload = {
    "token": "eyJhbGciOiJFUzI1NiIsInR5cCI6IkpXVCJ9...",
    "token_usage": "cookie"
}
headers = {"Content-Type": "application/json"}

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

print(response.json())
```

```javascript Authentication_postAuthLogin_example
const url = 'http://os-992244000006.local/api/v1/auth/login';
const options = {
  method: 'POST',
  headers: {'Content-Type': 'application/json'},
  body: '{"token":"eyJhbGciOiJFUzI1NiIsInR5cCI6IkpXVCJ9...","token_usage":"cookie"}'
};

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

```go Authentication_postAuthLogin_example
package main

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

func main() {

	url := "http://os-992244000006.local/api/v1/auth/login"

	payload := strings.NewReader("{\n  \"token\": \"eyJhbGciOiJFUzI1NiIsInR5cCI6IkpXVCJ9...\",\n  \"token_usage\": \"cookie\"\n}")

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

	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 Authentication_postAuthLogin_example
require 'uri'
require 'net/http'

url = URI("http://os-992244000006.local/api/v1/auth/login")

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

request = Net::HTTP::Post.new(url)
request["Content-Type"] = 'application/json'
request.body = "{\n  \"token\": \"eyJhbGciOiJFUzI1NiIsInR5cCI6IkpXVCJ9...\",\n  \"token_usage\": \"cookie\"\n}"

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

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

HttpResponse<String> response = Unirest.post("http://os-992244000006.local/api/v1/auth/login")
  .header("Content-Type", "application/json")
  .body("{\n  \"token\": \"eyJhbGciOiJFUzI1NiIsInR5cCI6IkpXVCJ9...\",\n  \"token_usage\": \"cookie\"\n}")
  .asString();
```

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

$client = new \GuzzleHttp\Client();

$response = $client->request('POST', 'http://os-992244000006.local/api/v1/auth/login', [
  'body' => '{
  "token": "eyJhbGciOiJFUzI1NiIsInR5cCI6IkpXVCJ9...",
  "token_usage": "cookie"
}',
  'headers' => [
    'Content-Type' => 'application/json',
  ],
]);

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

```csharp Authentication_postAuthLogin_example
using RestSharp;

var client = new RestClient("http://os-992244000006.local/api/v1/auth/login");
var request = new RestRequest(Method.POST);
request.AddHeader("Content-Type", "application/json");
request.AddParameter("application/json", "{\n  \"token\": \"eyJhbGciOiJFUzI1NiIsInR5cCI6IkpXVCJ9...\",\n  \"token_usage\": \"cookie\"\n}", ParameterType.RequestBody);
IRestResponse response = client.Execute(request);
```

```swift Authentication_postAuthLogin_example
import Foundation

let headers = ["Content-Type": "application/json"]
let parameters = [
  "token": "eyJhbGciOiJFUzI1NiIsInR5cCI6IkpXVCJ9...",
  "token_usage": "cookie"
] as [String : Any]

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

let request = NSMutableURLRequest(url: NSURL(string: "http://os-992244000006.local/api/v1/auth/login")! 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()
```