# Update dataset version

**PATCH** `/v1/private/datasets/{id}/versions/hash/{versionHash}`

Update a dataset version's change_description and/or add new tags

Base URL: `https://www.comet.com/opik/api`

Tags: `Datasets`

## Authorization

This operation requires no authorization.

## Path parameters

| Name | Type | Required | Description |
| --- | --- | --- | --- |
| `versionHash` | `string` | Yes | — |
| `id` | `string` (uuid) | Yes | — |

## Request body

Optional. Media type: `application/json`

### Example request body

```json
{
  "change_description": "Updated baseline version",
  "tags_to_add": [
    "production",
    "reviewed"
  ]
}
```

## Responses

| Status | Description | Media type |
| --- | --- | --- |
| `200` | Version updated successfully | `application/json` |
| `400` | Bad Request | `application/json` |
| `404` | Not Found - Version not found | `application/json` |
| `409` | Conflict - Tag already exists | `application/json` |

### Example response: 200 — Version updated successfully

```json
{
  "change_description": "string",
  "created_at": "2026-06-09T00:00:00Z",
  "created_by": "string",
  "dataset_id": "00000000-0000-0000-0000-000000000000",
  "evaluators": [
    {
      "config": {},
      "name": "string",
      "type": "code_metric"
    }
  ],
  "execution_policy": {
    "pass_threshold": 0,
    "runs_per_item": 0
  },
  "id": "00000000-0000-0000-0000-000000000000",
  "is_latest": true,
  "items_added": 0,
  "items_deleted": 0,
  "items_modified": 0,
  "items_total": 0,
  "last_updated_at": "2026-06-09T00:00:00Z",
  "last_updated_by": "string",
  "metadata": {
    "additionalProp1": "string"
  },
  "tags": [
    "string"
  ],
  "version_hash": "string",
  "version_name": "string"
}
```

### Example response: 400 — Bad Request

```json
{
  "code": 0,
  "details": "string",
  "message": "string"
}
```

### Example response: 404 — Not Found - Version not found

```json
{
  "code": 0,
  "details": "string",
  "message": "string"
}
```

### Example response: 409 — Conflict - Tag already exists

```json
{
  "code": 0,
  "details": "string",
  "message": "string"
}
```

## Related pages

- [Activate a pairing session](./activatepairingsession.md)
- [Add blueprint to existing config](./updateagentconfig.md)
- [Add items to annotation queue](./additemstoannotationqueue.md)
- [Add span comment](./addspancomment.md)
- [Add span feedback score](./addspanfeedbackscore.md)
- [Add thread comment](./addthreadcomment.md)
- [Add trace comment](./addtracecomment.md)
- [Add trace feedback score](./addtracefeedbackscore.md)
- [Agent Configs](./tags/agent-configs.md)
- [Agent Insights](./tags/agent-insights.md)

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