# POST Create a material

Adds a material to the customiser, at the end of the current presentation order. Only `name` is required; every other field has a documented default (both exclusion arrays empty, `base_price` 0, `price_multiplier` 1, `price_multiplier_target` base_letter_price). `excluded_backboard_ids` and `excluded_mounting_ids` must name the customiser's own backboards and mountings — an id from another customiser or another store is a 422 on the offending element. Image fields are read-only until the upload surface ships, and `sort_order` moves only through the reorder operation; naming either is a 422. Requires `customisers:write` and an `Idempotency-Key`. The write clears the customiser's cached storefront configuration and runs the advisory language sync. It never regenerates Shopify products, product images, or the product cache, so live listings are untouched. Option writes also spend one unit of a separate per-key option-write budget; exhausting it returns a 429 with `retry_after`.

- Source URL: https://www.signcustomiser.com/help/api/v3-post-create-a-material/
- Markdown URL: https://www.signcustomiser.com/help/api/v3-post-create-a-material.md
- Group: Customiser materials
- Method: POST
- Path: /api/v3/customisers/{customiser_id}/materials
- Auth: Bearer token
- Required scopes: `customisers:write`

## Path parameters

- customiser_id (string, required): The customiser id. Example: 1

## Body parameters

- price_multiplier_target (string, optional): No description provided.
- name (string, optional): No description provided.
- description (string, optional): No description provided.
- excluded_backboard_ids (array, optional): No description provided.
- excluded_mounting_ids (array, optional): No description provided.
- base_price (integer, optional): No description provided.
- price_multiplier (number, optional): No description provided.

## Request body example

```json
{
  "price_multiplier_target": "base_letter_price",
  "name": "Brushed Aluminium",
  "description": "3mm brushed aluminium face",
  "excluded_backboard_ids": [
    11
  ],
  "excluded_mounting_ids": [
    4
  ],
  "base_price": 500,
  "price_multiplier": 1.2
}
```

## cURL example

```bash
curl https://web.signcustomiser.com/api/v3/customisers/1/materials \
  --request POST \
  --header 'Accept: application/json' \
  --header 'Authorization: Bearer YOUR_API_TOKEN' \
  --header 'Content-Type: application/json' \
  --data '{
  "price_multiplier_target": "base_letter_price",
  "name": "Brushed Aluminium",
  "description": "3mm brushed aluminium face",
  "excluded_backboard_ids": [
    11
  ],
  "excluded_mounting_ids": [
    4
  ],
  "base_price": 500,
  "price_multiplier": 1.2
}'
```

## Response examples

### 201 POST 201 example 1

```json
{
  "data": {
    "object": "material",
    "id": 5,
    "customiser_id": 42,
    "name": "Brushed Aluminium",
    "description": null,
    "excluded_backboard_ids": [],
    "excluded_mounting_ids": [],
    "base_price": 0,
    "currency": "USD",
    "price_multiplier": 1,
    "price_multiplier_target": "base_letter_price",
    "sort_order": 1,
    "image_url": null,
    "button_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/materials/5",
    "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 customiser

```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 Idempotency conflict

```json
{
  "type": "https://www.signcustomiser.com/help/api/problems/idempotency_key_conflict",
  "title": "Idempotency key conflict",
  "status": 409,
  "code": "idempotency_key_conflict",
  "detail": "This Idempotency-Key was already used for a different request body on this operation.",
  "request_id": "req_01jz9x2k7c8f3m5n6p7q8r9s0t"
}
```

### 413 Request body too large

```json
{
  "type": "https://www.signcustomiser.com/help/api/problems/request_too_large",
  "title": "Request too large",
  "status": 413,
  "code": "request_too_large",
  "detail": "The request body must not exceed 2 MiB.",
  "request_id": "req_01jz9x2k7c8f3m5n6p7q8r9s0t"
}
```

### 422 Foreign exclusion id

```json
{
  "type": "https://www.signcustomiser.com/help/api/problems/validation_failed",
  "title": "Validation failed",
  "status": 422,
  "code": "validation_failed",
  "detail": "The request payload failed validation.",
  "errors": [
    {
      "pointer": "/excluded_backboard_ids/0",
      "code": "invalid",
      "detail": "The selected backboard does not belong to this customiser."
    }
  ],
  "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"
}
```