> ## Documentation Index > Fetch the complete documentation index at: https://docs.autoprintfarm.com/llms.txt > Use this file to discover all available pages before exploring further. # Replace the BOM for a SKU > Replaces the SKU's full bill of materials atomically. Sending an empty `children` array clears the SKU back to non-composite. Nesting is capped at one level — composite children are rejected (NESTING_NOT_ALLOWED). ## OpenAPI ````yaml /api-reference/openapi.json put /skus/{id}/bom openapi: 3.1.0 info: title: AutoPrintFarm Public API version: 1.0.0 description: >- Public API for AutoPrintFarm — read + write surface for printers, jobs, inventory, orders, SKUs, files, worklist, and assembly. Authorization uses three scopes: `read` (any list/get), `write` (data mutations — create, update, delete, uploads, fulfillment), and `control` (physical printer actions: start, pause, resume, stop, heaters, light, filament). Authenticate with an API key minted from Settings → API Keys in the AutoPrintFarm dashboard. contact: name: AutoPrintFarm url: https://autoprintfarm.com servers: - url: https://api.autoprintfarm.com/public/v1 description: Production security: - bearerAuth: [] tags: - name: Printers description: Printer fleet status - name: Jobs description: Print job queue and history - name: Inventory description: Finished-goods stock levels - name: Orders description: Customer orders and line items - name: Wiki description: Internal documentation articles - name: Worklist description: Operational task queue - name: Products description: Product catalog, SKUs, components, and color presets - name: Files description: Print file metadata and versions - name: Hubs description: Hub fleet and connection status - name: Assembly description: Post-print assembly tasks with bundled wiki - name: Materials description: Filament, components, packaging, and printer parts inventory - name: Analytics description: >- Dashboard rollups and reporting (overview, production, printers, failures, inventory, revenue) paths: /skus/{id}/bom: put: tags: - Products summary: Replace the BOM for a SKU description: >- Replaces the SKU's full bill of materials atomically. Sending an empty `children` array clears the SKU back to non-composite. Nesting is capped at one level — composite children are rejected (NESTING_NOT_ALLOWED). parameters: - schema: type: string required: true name: id in: path requestBody: content: application/json: schema: type: object properties: children: type: array items: type: object properties: child_sku_id: type: string quantity_required: type: integer minimum: 1 required: - child_sku_id - quantity_required default: [] inventory: type: array items: type: object properties: inventory_type: type: string enum: - filament - packaging - accessory - printer_part inventory_item_id: type: string quantity_required: type: number exclusiveMinimum: 0 required: - inventory_type - inventory_item_id - quantity_required default: [] responses: '200': description: BOM replaced content: application/json: schema: type: object properties: success: type: boolean enum: - true data: $ref: '#/components/schemas/SkuBom' required: - success - data '400': description: Validation error (unknown child SKU, self-reference, etc.) content: application/json: schema: $ref: '#/components/schemas/Error' '401': description: Missing, invalid, revoked, or expired API key content: application/json: schema: $ref: '#/components/schemas/Error' '403': description: API key lacks the required scope content: application/json: schema: $ref: '#/components/schemas/Error' '404': description: SKU not found content: application/json: schema: $ref: '#/components/schemas/Error' '409': description: Nesting cap violated content: application/json: schema: $ref: '#/components/schemas/Error' '429': description: Rate limit exceeded (120 req/min/key) content: application/json: schema: $ref: '#/components/schemas/Error' security: - bearerAuth: - write components: schemas: SkuBom: type: object properties: sku_id: type: string is_composite: type: boolean available_to_build: type: number children: type: array items: type: object properties: child_sku_id: type: string quantity_required: type: number child_sku: type: - string - 'null' child_color: type: - string - 'null' child_is_composite: type: - boolean - 'null' child_ready_stock: type: number required: - child_sku_id - quantity_required - child_sku - child_color - child_is_composite - child_ready_stock inventory: type: array items: type: object properties: inventory_type: type: string enum: - filament - packaging - accessory - printer_part inventory_item_id: type: string quantity_required: type: number item_name: type: - string - 'null' remaining: type: number unit: type: string required: - inventory_type - inventory_item_id - quantity_required - item_name - remaining - unit required: - sku_id - is_composite - available_to_build - children - inventory Error: type: object properties: success: type: boolean enum: - false error: type: object properties: code: type: string description: >- Machine-readable error code (e.g. NOT_FOUND, VALIDATION_ERROR, FORBIDDEN, HUB_OFFLINE). Stable across releases — use this for branching. example: NOT_FOUND message: type: string description: >- Human-readable error message. May vary across releases — do not branch on this. example: Resource not found details: description: >- Optional structured detail. For VALIDATION_ERROR this is `{ field: [messages] }`. required: - code - message description: Error detail object required: - success - error description: Standard error response envelope securitySchemes: bearerAuth: type: http scheme: bearer bearerFormat: apf_live_<64 hex> description: >- API keys are minted in the AutoPrintFarm web app under Settings → API Keys. Send as `Authorization: Bearer apf_live_...`. Keys are shown exactly once at creation and can be revoked at any time. ````