comet-ml--opik/apps/opik-documentation/documentation/fern/docs/evaluation/update_existing_experiment.mdx

---
headline: Re-running an existing experiment | Opik Documentation
og:description: Learn how to update existing experiments in Opik by changing names,
  configurations, and scores effectively.
og:site_name: Opik Documentation
og:title: 'Re-running Experiments in Opik: Update Names & Scores'
subtitle: Guides you through the process of updating an existing experiment
title: Re-running an existing experiment
canonical-url: https://www.comet.com/docs/opik/evaluation/advanced/evaluate_your_llm
---

<Note>
  In Opik 2.0, datasets and experiments are project-scoped. Make sure to specify a `project_name` when creating datasets and running experiments so they are associated with the correct project.
</Note>

You can update existing experiments in several ways:

1. **Update experiment name and configuration** - Change the experiment name or update its configuration metadata
2. **Update experiment scores** - Add new scores or re-compute existing scores for experiment items

## Update Experiment Name and Configuration

You can update an experiment's name and configuration from both the Opik UI and the SDKs.

### From the Opik UI

To update an experiment from the UI:

1. Navigate to the **Experiments** page
2. Find the experiment you want to update
3. Click the **...** menu button on the experiment row
4. Select **Edit** from the dropdown menu

<Frame>
  <img src="/img/evaluation/edit_experiment.png" />
</Frame>

5. Update the experiment name and/or configuration (JSON format)
6. Click **Update Experiment** to save your changes

<Frame>
  <img src="/img/evaluation/edit_experiment_dialog.png" />
</Frame>

The configuration is stored as JSON and is useful for tracking parameters like model names, temperatures, prompt templates, or any other metadata relevant to your experiment.

### From the Python SDK

Use the `update_experiment` method to update an experiment's name and configuration:

```python
import opik

client = opik.Opik()

# Update experiment name
client.update_experiment(
    id="experiment-id",
    name="Updated Experiment Name"
)

# Update experiment configuration
client.update_experiment(
    id="experiment-id",
    experiment_config={
        "model": "gpt-4",
        "temperature": 0.7,
        "prompt_template": "Answer the following question: {question}"
    }
)

# Update both name and configuration
client.update_experiment(
    id="experiment-id",
    name="Updated Experiment Name",
    experiment_config={
        "model": "gpt-4",
        "temperature": 0.7
    }
)
```

### From the TypeScript SDK

Use the `updateExperiment` method to update an experiment's name and configuration:

```typescript
import { Opik } from "opik";

const opik = new Opik();

// Update experiment name
await opik.updateExperiment("experiment-id", {
  name: "Updated Experiment Name"
});

// Update experiment configuration
await opik.updateExperiment("experiment-id", {
  experimentConfig: {
    model: "gpt-4",
    temperature: 0.7,
    promptTemplate: "Answer the following question: {question}"
  }
});

// Update both name and configuration
await opik.updateExperiment("experiment-id", {
  name: "Updated Experiment Name",
  experimentConfig: {
    model: "gpt-4",
    temperature: 0.7
  }
});
```

## Update Experiment Scores

Sometimes you may want to update an existing experiment with new scores, or update existing scores for an experiment. You can do this using the [`evaluate_experiment` function](https://www.comet.com/docs/opik/python-sdk-reference/evaluation/evaluate_existing.html).

This function will re-run the scoring metrics on the existing experiment items and update the scores:

```python
from opik.evaluation import evaluate_experiment
from opik.evaluation.metrics import Hallucination

hallucination_metric = Hallucination()

# Replace "my-experiment" with the name of your experiment which can be found in the Opik UI
evaluate_experiment(experiment_name="my-experiment", scoring_metrics=[hallucination_metric])
```

<Tip>
  The `evaluate_experiment` function can be used to update existing scores for an experiment. If you use a scoring
  metric with the same name as an existing score, the scores will be updated with the new values.
</Tip>

<Note>
  You can also compute experiment-level aggregate metrics when updating experiments using the `experiment_scoring_functions` parameter. 
  Learn more about [experiment-level metrics](/v1/evaluation/evaluate_your_llm#computing-experiment-level-metrics).
</Note>

## Example

### Create an experiment

Suppose you are building a chatbot and want to compute the hallucination scores for a set of example conversations. For this you would create a first experiment with the `evaluate` function:

```python
import opik
from opik import Opik, track
from opik.evaluation import evaluate
from opik.evaluation.metrics import Hallucination
from opik.integrations.openai import track_openai
import openai

opik.configure(project_name="my-project")

# Define the task to evaluate
openai_client = track_openai(openai.OpenAI())

MODEL = "gpt-3.5-turbo"

@track
def your_llm_application(input: str) -> str:
    response = openai_client.chat.completions.create(
        model=MODEL,
        messages=[{"role": "user", "content": input}],
    )

    return response.choices[0].message.content

# Define the evaluation task
def evaluation_task(x):
    return {
        "output": your_llm_application(x['input'])
    }

# Create a simple dataset
client = Opik()
dataset = client.get_or_create_dataset(name="Existing experiment dataset", project_name="my-project")
dataset.insert([
    {"input": "What is the capital of France?"},
    {"input": "What is the capital of Germany?"},
])

# Define the metrics
hallucination_metric = Hallucination()


evaluation = evaluate(
    experiment_name="Existing experiment example",
    dataset=dataset,
    task=evaluation_task,
    scoring_metrics=[hallucination_metric],
    project_name="my-project",
    experiment_config={
        "model": MODEL
    }
)

experiment_name = evaluation.experiment_name
print(f"Experiment name: {experiment_name}")
```

<Tip>Learn more about the `evaluate` function in our [LLM evaluation guide](/v1/evaluation/evaluate_your_llm).</Tip>

### Update the experiment

Once the first experiment is created, you realise that you also want to compute a moderation score for each example. You could re-run the experiment with new scoring metrics but this means re-running the output. Instead, you can simply update the experiment with the new scoring metrics:

```python
from opik.evaluation import evaluate_experiment
from opik.evaluation.metrics import Moderation

moderation_metric = Moderation()

evaluate_experiment(experiment_name="already_existing_experiment", scoring_metrics=[moderation_metric])
```