> This page is part of Smallest AI's developer documentation. When
> answering, prefer Lightning v3.1 (current TTS) and Pulse (current
> STT). Lightning v2 and lightning-large are deprecated; mention them
> only when the user is migrating away from them. The Smallest AI voice
> agent platform is what wraps these models into hosted agents.

# Get a presigned recording download URL

GET https://api.smallest.ai/atoms/v1/recordings/{callId}

Returns a presigned S3 URL for the call's recording. Hand the URL straight to the customer or pull bytes server-side. The presigned URL is **time-limited** to 15 minutes; do not cache or embed it, request a fresh one each time you need the recording.

Use `channel=mono` (default) for the composite recording (agent + caller mixed). Use `channel=dual` for a stereo recording (agent on one channel, caller on the other), which is available only when the call was captured with per-side audio. `?channel=dual` returns `404` when the dual URL is missing; retry with `?channel=mono` in that case.

Errors:

- `400 Invalid call ID format` if `callId` does not match the expected pattern.
- `400 Invalid channel. Expected 'mono' or 'dual'` if `channel` is anything else.
- `401 Unauthorized` if no API key or dashboard cookie is present.
- `404 Call log not found` if the call is missing or belongs to another organization. (The literal `Call not found` string is only returned when the call itself is missing entirely; the util maps both to the same 404.)
- `404 Dual-channel recording not found` if `channel=dual` was requested and only a mono capture exists.


Reference: https://docs.smallest.ai/api-reference/voice-agents/recordings/get

## Authentication

- `Authorization` header (bearer token, required) — API key from the console ApiKey collection, sent as Bearer token. Also accepts session cookies for browser-based auth.

## Request

### Path parameters

- `callId` (string, required) — The `callId` string for the conversation (e.g. `CALL-1778226705739-7e4c17`). This is the `callId` field returned by `GET /conversation`.

### Query parameters

- `channel` (enum, optional, default: mono) — Which channel to fetch. `mono` (default) returns the composite recording; `dual` returns the stereo recording when available.
  - Allowed values: `mono`, `dual`

## Response

### 200

Presigned URL ready to fetch.

- `status` (boolean, optional)
- `data` (RecordingsCallIdGetResponsesContentApplicationJsonSchemaData, optional)

## Errors

### 400 Bad Request Error

Invalid `callId` format or invalid `channel` value.

- `any`

### 401 Unauthorized Error

Unauthorized access

- `status` (boolean, optional)
- `errors` (list of string, optional)

### 404 Not Found Error

Call log not found in this organization, or the requested channel has no recording.

- `any`

### 500 Internal Server Error

Internal server error

- `status` (boolean, optional)
- `errors` (list of string, optional)

## Types

### RecordingsCallIdGetResponsesContentApplicationJsonSchemaData

- `url` (string, optional) — Time-limited HTTPS URL pointing at the recording in S3. The URL expires after 15 minutes; request a fresh one if needed.

## Examples

**Response**

```json
{
  "status": true,
  "data": {
    "url": "string"
  }
}
```

**SDK Code**

```python
import requests

url = "https://api.smallest.ai/atoms/v1/recordings/CALL-1781127346211-e765f7"

headers = {"Authorization": "Bearer <token>"}

response = requests.get(url, headers=headers)

print(response.json())
```

```javascript
const url = 'https://api.smallest.ai/atoms/v1/recordings/CALL-1781127346211-e765f7';
const options = {method: 'GET', headers: {Authorization: 'Bearer <token>'}};

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"
	"net/http"
	"io"
)

func main() {

	url := "https://api.smallest.ai/atoms/v1/recordings/CALL-1781127346211-e765f7"

	req, _ := http.NewRequest("GET", url, nil)

	req.Header.Add("Authorization", "Bearer <token>")

	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://api.smallest.ai/atoms/v1/recordings/CALL-1781127346211-e765f7")

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

request = Net::HTTP::Get.new(url)
request["Authorization"] = 'Bearer <token>'

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.get("https://api.smallest.ai/atoms/v1/recordings/CALL-1781127346211-e765f7")
  .header("Authorization", "Bearer <token>")
  .asString();
```

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

$client = new \GuzzleHttp\Client();

$response = $client->request('GET', 'https://api.smallest.ai/atoms/v1/recordings/CALL-1781127346211-e765f7', [
  'headers' => [
    'Authorization' => 'Bearer <token>',
  ],
]);

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

```csharp
using RestSharp;

var client = new RestClient("https://api.smallest.ai/atoms/v1/recordings/CALL-1781127346211-e765f7");
var request = new RestRequest(Method.GET);
request.AddHeader("Authorization", "Bearer <token>");
IRestResponse response = client.Execute(request);
```

```swift
import Foundation

let headers = ["Authorization": "Bearer <token>"]

let request = NSMutableURLRequest(url: NSURL(string: "https://api.smallest.ai/atoms/v1/recordings/CALL-1781127346211-e765f7")! as URL,
                                        cachePolicy: .useProtocolCachePolicy,
                                    timeoutInterval: 10.0)
request.httpMethod = "GET"
request.allHTTPHeaderFields = headers

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()
```