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# Create or update an extension

PUT https://api.contentful.com/spaces/{space_id}/environments/{environment_id}/extensions/{extension_id}
Content-Type: application/vnd.contentful.management.v1+json

Use this endpoint to create a new extension with a specified ID, or to update a specific extension via its ID. When updating an existing extension, you need to specify the last version of the extension you are updating with `X-Contentful-Version`.

Reference: https://contentful.com/developers/docs/references/content-management-api/ui-extensions/create-or-update-an-extension

## Authentication

- `Authorization` header (bearer token, required) — Bearer authentication of the form `Bearer <token>`, where token is your auth token.

## Request

### Path parameters

- `space_id` (string, required) — ID of the space in form of a string
- `environment_id` (string, required) — ID of the environment in form of a string
- `extension_id` (string, required) — ID of the extension in form of a string

### Headers

- `X-Contentful-Version` (string, optional) — Version of the extension to update

### Body (application/vnd.contentful.management.v1+json)

This endpoint expects a map from string to any.

- `map from string to any`

## Response

### 200

OK - Request successful

- `map from string to any`

## Examples

**Request**

```json
{
  "extension": {
    "fieldTypes": [
      {
        "type": "Symbol"
      },
      {
        "type": "Text"
      }
    ],
    "name": "My awesome extension",
    "sidebar": false,
    "src": "https://example.com/my"
  }
}
```

**Response**

```json
{
  "extension": {
    "fieldTypes": [
      {
        "type": "Symbol"
      },
      {
        "type": "Text"
      }
    ],
    "name": "My awesome extension",
    "sidebar": false,
    "src": "https://example.com/my"
  },
  "sys": {
    "createdAt": "2025-07-04T20:43:40.000Z",
    "createdBy": {
      "sys": {
        "id": "7BslKh9TdKGOK41VmLDjFZ",
        "linkType": "User",
        "type": "Link"
      }
    },
    "environment": {
      "sys": {
        "id": "staging",
        "linkType": "Environment",
        "type": "Link"
      }
    },
    "id": "0xvkPW9FdQ1kkWlWZ8ga4x",
    "space": {
      "sys": {
        "id": "yadj1kx9rmg0",
        "linkType": "Space",
        "type": "Link"
      }
    },
    "type": "Extension",
    "updatedAt": "2025-07-04T20:43:40.000Z",
    "updatedBy": {
      "sys": {
        "id": "4FLrUHftHW3v2BLi9fzfjU",
        "linkType": "User",
        "type": "Link"
      }
    },
    "version": 1
  }
}
```