# DELETE Delete a letter-part colour selection

Removes a letter part's colour selection and returns a deletion receipt: a snapshot of exactly what was removed, so the caller can verify and report the change. The delete is guarded harder than an option row's, because it removes a whole selection bucket. A bucket that still holds colours, is shared, or has translated copy is refused with a 409 `resource_in_use` naming what points at it. A part the letter type still lists in `letter_parts`, or one whose configuration or uploaded image has been changed from its defaults, is refused with a 422 `letter_part_not_deletable` carrying the `reason`: drop the part from the letter type, or reset what was changed, and retry. Requires `customisers:write` and an `Idempotency-Key`; retrying the same request and key replays the original receipt after the bucket is gone.

- Source URL: https://www.signcustomiser.com/help/api/v3-delete-delete-a-letter-part-colour-selection/
- Markdown URL: https://www.signcustomiser.com/help/api/v3-delete-delete-a-letter-part-colour-selection.md
- Group: Customiser letter parts
- Method: DELETE
- Path: /api/v3/customisers/{customiser_id}/letter-types/{letter_type_id}/letter-parts/{letter_part}
- Auth: Bearer token
- Required scopes: `customisers:write`

## Path parameters

- customiser_id (string, required): The customiser id. Example: 1
- letter_type_id (string, required): The letter type id. Example: 7
- letter_part (string, required): The letter part. Example: halo

## cURL example

```bash
curl https://web.signcustomiser.com/api/v3/customisers/1/letter-types/7/letter-parts/halo \
  --request DELETE \
  --header 'Accept: application/json' \
  --header 'Authorization: Bearer YOUR_API_TOKEN'
```

## Response examples

### 200 DELETE 200 example 1

```json
{
  "data": {
    "object": "letter_part_colour_selection_deletion_receipt",
    "customiser_id": 42,
    "letter_type_id": 7,
    "letter_part": "halo",
    "deleted": true,
    "resource": {
      "object": "letter_part_colour_selection",
      "customiser_id": 42,
      "letter_type_id": 7,
      "letter_part": "halo",
      "name": null,
      "description": null,
      "optional": null,
      "optional_label": null,
      "optional_default_none": false,
      "lightsource": false,
      "custom_image": false,
      "show_default_upload_image": true,
      "show_in_text_editor": true,
      "text_enabled": false,
      "default_upload_image_url": null,
      "created_at": "2026-08-13T00:00:00Z",
      "updated_at": "2026-08-13T00:00:00Z"
    }
  },
  "links": {
    "self": "https://web.signcustomiser.com/api/v3/customisers/42/letter-types/7/letter-parts/halo",
    "documentation": "https://www.signcustomiser.com/help/api/"
  },
  "meta": {
    "api_version": "v3",
    "request_id": "req_01jz9x2k7c8f3m5n6p7q8r9s0t"
  }
}
```

### 400 Missing idempotency key

```json
{
  "type": "https://www.signcustomiser.com/help/api/problems/missing_idempotency_key",
  "title": "Missing idempotency key",
  "status": 400,
  "code": "missing_idempotency_key",
  "detail": "Provide an Idempotency-Key header for this write.",
  "request_id": "req_01jz9x2k7c8f3m5n6p7q8r9s0t"
}
```

### 401 Missing API key

```json
{
  "type": "https://www.signcustomiser.com/help/api/problems/missing_api_key",
  "title": "Missing API key",
  "status": 401,
  "code": "missing_api_key",
  "detail": "Provide a store API key as a bearer token.",
  "request_id": "req_01jz9x2k7c8f3m5n6p7q8r9s0t"
}
```

### 403 Insufficient scope

```json
{
  "type": "https://www.signcustomiser.com/help/api/problems/insufficient_scope",
  "title": "Insufficient scope",
  "status": 403,
  "code": "insufficient_scope",
  "detail": "This operation requires the customisers:write scope.",
  "required_scopes": [
    "customisers:write"
  ],
  "granted_scopes": [
    "customisers:read"
  ],
  "request_id": "req_01jz9x2k7c8f3m5n6p7q8r9s0t"
}
```

### 404 Unknown letter part

```json
{
  "type": "https://www.signcustomiser.com/help/api/problems/resource_not_found",
  "title": "Resource not found",
  "status": 404,
  "code": "resource_not_found",
  "detail": "The requested resource does not exist or does not belong to the authenticated store.",
  "request_id": "req_01jz9x2k7c8f3m5n6p7q8r9s0t"
}
```

### 409 Colour selection still in use

```json
{
  "type": "https://www.signcustomiser.com/help/api/problems/resource_in_use",
  "title": "Resource in use",
  "status": 409,
  "code": "resource_in_use",
  "detail": "This letter part still has records pointing at its colour selection.",
  "errors": [
    {
      "pointer": "",
      "code": "resource_in_use",
      "detail": "The letter part is referenced by other records."
    }
  ],
  "reason": "selection_not_empty",
  "referenced_by": [
    {
      "type": "colour",
      "id": 31
    }
  ],
  "referenced_by_count": 1,
  "request_id": "req_01jz9x2k7c8f3m5n6p7q8r9s0t"
}
```

### 422 Letter part still configured

```json
{
  "type": "https://www.signcustomiser.com/help/api/problems/letter_part_not_deletable",
  "title": "Letter part not deletable",
  "status": 422,
  "code": "letter_part_not_deletable",
  "detail": "This letter part cannot be removed in the state it is in.",
  "errors": [
    {
      "pointer": "",
      "code": "letter_part_not_deletable",
      "detail": "The letter part cannot be deleted: configured_letter_part."
    }
  ],
  "reason": "configured_letter_part",
  "request_id": "req_01jz9x2k7c8f3m5n6p7q8r9s0t"
}
```

### 429 Option write budget exhausted

```json
{
  "type": "https://www.signcustomiser.com/help/api/problems/rate_limited",
  "title": "Too many requests",
  "status": 429,
  "code": "rate_limited",
  "detail": "You have exceeded the request limit for this API key.",
  "retry_after": 37,
  "request_id": "req_01jz9x2k7c8f3m5n6p7q8r9s0t"
}
```