# Create blueprint from mask

**POST** `/v1/private/agent-configs/blueprints/projects/{project_id}/masks/{mask_id}`

Creates a new blueprint by applying a mask's changes on top of the latest blueprint for the project.

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

Tags: `Agent Configs`

## Authorization

This operation requires no authorization.

## Path parameters

| Name | Type | Required | Description |
| --- | --- | --- | --- |
| `project_id` | `string` (uuid) | Yes | — |
| `mask_id` | `string` (uuid) | Yes | — |

## Responses

| Status | Description | Media type |
| --- | --- | --- |
| `201` | Created | — |
| `401` | Unauthorized | `application/json` |
| `404` | Not Found (no config or mask not found) | `application/json` |

### Example response: 401 — Unauthorized

```json
{
  "errors": [
    "string"
  ]
}
```

### Example response: 404 — Not Found (no config or mask not found)

```json
{
  "errors": [
    "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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