> For clean Markdown of any page, append .md to the page URL.
> For a complete documentation index, see https://humanloop.com/docs/v4/api/sessions/get/llms.txt.
> For AI client integration (Claude Code, Cursor, etc.), connect to the MCP server at https://humanloop.com/_mcp/server.

# Get

GET https://api.humanloop.com/v4/sessions/{id}

Get a session by ID.

Reference: https://humanloop.com/docs/v4/api/sessions/get

## Authentication

- `X-API-KEY` header (required) — API Key authentication via header

## Request

### Path parameters

- `id` (string, required) — String ID of session to return. Starts with `sesh_`.

## Response

### 200

Successful Response

- `id` (string, required) — String ID of session. Starts with `sesh_`.
- `projects` (list of SessionProjectResponse, required) — List of projects that have datapoints associated to this session.
- `datapoints_count` (integer, required) — Number of datapoints associated to this session.
- `created_at` (datetime, required)
- `updated_at` (datetime, required)
- `reference_id` (string, optional) — Unique user-provided string identifying the session.
- `first_inputs` (map from string to any, optional) — Inputs for the first datapoint in the session.
- `last_output` (string, optional) — Output for the last datapoint in the session.

## Errors

### 422 Sessions Get Request Unprocessable Entity Error

Validation Error

- `detail` (list of ValidationError, optional)

## Types

### SessionProjectResponse

- `id` (string, required) — String ID of project the datapoint belongs to. Starts with `pr_`.
- `name` (string, required)
- `type` (enum, required) — Type of project. e.g. `prompt` or `tool`.
  - Allowed values: `prompt`, `tool`, `dataset`, `evaluator`, `flow`, `agent`

### ValidationError

- `loc` (list of ValidationErrorLocItem, required)
- `msg` (string, required)
- `type` (string, required)

### ValidationErrorLocItem

## Examples

**Response**

```json
{
  "id": "id",
  "projects": [
    {
      "id": "id",
      "name": "name",
      "type": "prompt"
    }
  ],
  "datapoints_count": 1,
  "created_at": "2024-01-15T09:30:00Z",
  "updated_at": "2024-01-15T09:30:00Z",
  "reference_id": "reference_id",
  "first_inputs": {
    "key": "value"
  },
  "last_output": "last_output"
}
```

**SDK Code**

```python
import requests

url = "https://api.humanloop.com/v4/sessions/id"

headers = {"X-API-KEY": "<apiKey>"}

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

print(response.json())
```

```javascript
const url = 'https://api.humanloop.com/v4/sessions/id';
const options = {method: 'GET', headers: {'X-API-KEY': '<apiKey>'}};

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.humanloop.com/v4/sessions/id"

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

	req.Header.Add("X-API-KEY", "<apiKey>")

	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.humanloop.com/v4/sessions/id")

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

request = Net::HTTP::Get.new(url)
request["X-API-KEY"] = '<apiKey>'

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.humanloop.com/v4/sessions/id")
  .header("X-API-KEY", "<apiKey>")
  .asString();
```

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

$client = new \GuzzleHttp\Client();

$response = $client->request('GET', 'https://api.humanloop.com/v4/sessions/id', [
  'headers' => [
    'X-API-KEY' => '<apiKey>',
  ],
]);

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

```csharp
using RestSharp;

var client = new RestClient("https://api.humanloop.com/v4/sessions/id");
var request = new RestRequest(Method.GET);
request.AddHeader("X-API-KEY", "<apiKey>");
IRestResponse response = client.Execute(request);
```

```swift
import Foundation

let headers = ["X-API-KEY": "<apiKey>"]

let request = NSMutableURLRequest(url: NSURL(string: "https://api.humanloop.com/v4/sessions/id")! 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()
```