> For clean Markdown of any page, append .md to the page URL.
> For a complete documentation index, see https://www.comet.com/docs/opik/reference/rest-api/experiments/execute-experiment/llms.txt.

# Create and execute experiment

POST http://localhost:5173/api/v1/private/experiments/execute
Content-Type: application/json

Creates experiments for each prompt variant and asynchronously processes all dataset items

Reference: https://www.comet.com/docs/opik/reference/rest-api/experiments/execute-experiment

## Servers

- `http://localhost:5173/api` (Local server, default)
- `https://www.comet.com/opik/api` (Opik Cloud)

## Request

### Body (application/json)

This endpoint expects an ExperimentExecutionRequest.

- `dataset_name` (string, required)
- `prompts` (list of PromptVariant, required)
- `dataset_id` (string, required)
- `dataset_version_id` (string, optional)
- `project_name` (string, optional)
- `version_hash` (string, optional)
- `prompt_versions` (list of PromptVersionLink, optional)

## Response

### 202

Experiments created and processing started

- `experiments` (list of ExperimentInfo, optional)
- `total_items` (integer, optional)

## Types

### PromptVariant

- `model` (string, required)
- `messages` (list of Message, required)
- `configs` (map from string to JsonNode, optional)
- `prompt_versions` (list of PromptVersionLink, optional)
- `experiment_name` (string, optional)

### PromptVersionLink

- `id` (string, required)
- `commit` (string, optional)
- `version_number` (string, optional) — sequential version number in the format v\<N>; null for masks
- `prompt_id` (string, optional)
- `prompt_name` (string, optional)

### ExperimentInfo

- `experiment_id` (string, optional)
- `prompt_index` (integer, optional)

### Message

- `role` (string, required)
- `content` (JsonNode, required)

### JsonNode

## Examples

**Request**

```json
{
  "dataset_name": "string",
  "prompts": [
    {
      "model": "string",
      "messages": [
        {
          "role": "string",
          "content": {}
        }
      ]
    }
  ],
  "dataset_id": "string"
}
```

**Response**

```json
{
  "experiments": [
    {
      "experiment_id": "string",
      "prompt_index": 1
    }
  ],
  "total_items": 1
}
```

**SDK Code**

```python
import requests

url = "http://localhost:5173/api/v1/private/experiments/execute"

payload = {
    "dataset_name": "string",
    "prompts": [
        {
            "model": "string",
            "messages": [
                {
                    "role": "string",
                    "content": {}
                }
            ]
        }
    ],
    "dataset_id": "string"
}
headers = {"Content-Type": "application/json"}

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

print(response.json())
```

```javascript
const url = 'http://localhost:5173/api/v1/private/experiments/execute';
const options = {
  method: 'POST',
  headers: {'Content-Type': 'application/json'},
  body: '{"dataset_name":"string","prompts":[{"model":"string","messages":[{"role":"string","content":{}}]}],"dataset_id":"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 := "http://localhost:5173/api/v1/private/experiments/execute"

	payload := strings.NewReader("{\n  \"dataset_name\": \"string\",\n  \"prompts\": [\n    {\n      \"model\": \"string\",\n      \"messages\": [\n        {\n          \"role\": \"string\",\n          \"content\": {}\n        }\n      ]\n    }\n  ],\n  \"dataset_id\": \"string\"\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
require 'uri'
require 'net/http'

url = URI("http://localhost:5173/api/v1/private/experiments/execute")

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

request = Net::HTTP::Post.new(url)
request["Content-Type"] = 'application/json'
request.body = "{\n  \"dataset_name\": \"string\",\n  \"prompts\": [\n    {\n      \"model\": \"string\",\n      \"messages\": [\n        {\n          \"role\": \"string\",\n          \"content\": {}\n        }\n      ]\n    }\n  ],\n  \"dataset_id\": \"string\"\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("http://localhost:5173/api/v1/private/experiments/execute")
  .header("Content-Type", "application/json")
  .body("{\n  \"dataset_name\": \"string\",\n  \"prompts\": [\n    {\n      \"model\": \"string\",\n      \"messages\": [\n        {\n          \"role\": \"string\",\n          \"content\": {}\n        }\n      ]\n    }\n  ],\n  \"dataset_id\": \"string\"\n}")
  .asString();
```

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

$client = new \GuzzleHttp\Client();

$response = $client->request('POST', 'http://localhost:5173/api/v1/private/experiments/execute', [
  'body' => '{
  "dataset_name": "string",
  "prompts": [
    {
      "model": "string",
      "messages": [
        {
          "role": "string",
          "content": {}
        }
      ]
    }
  ],
  "dataset_id": "string"
}',
  'headers' => [
    'Content-Type' => 'application/json',
  ],
]);

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

```csharp
using RestSharp;

var client = new RestClient("http://localhost:5173/api/v1/private/experiments/execute");
var request = new RestRequest(Method.POST);
request.AddHeader("Content-Type", "application/json");
request.AddParameter("application/json", "{\n  \"dataset_name\": \"string\",\n  \"prompts\": [\n    {\n      \"model\": \"string\",\n      \"messages\": [\n        {\n          \"role\": \"string\",\n          \"content\": {}\n        }\n      ]\n    }\n  ],\n  \"dataset_id\": \"string\"\n}", ParameterType.RequestBody);
IRestResponse response = client.Execute(request);
```

```swift
import Foundation

let headers = ["Content-Type": "application/json"]
let parameters = [
  "dataset_name": "string",
  "prompts": [
    [
      "model": "string",
      "messages": [
        [
          "role": "string",
          "content": []
        ]
      ]
    ]
  ],
  "dataset_id": "string"
] as [String : Any]

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

let request = NSMutableURLRequest(url: NSURL(string: "http://localhost:5173/api/v1/private/experiments/execute")! 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()
```

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