> ## Documentation Index > Fetch the complete documentation index at: https://docs.vellaro.io/llms.txt > Use this file to discover all available pages before exploring further. # List Categories > Return all active categories — flat or nested tree. The tree is assembled in Python from ONE flat query (active, not soft-deleted), like `admin_list_categories`. The old version validated the ORM rows recursively over `selectinload(Category.children)`: that relation is unfiltered, so a deleted/inactive child came along, and its own (unloaded) children → MissingGreenlet → 500 on the whole public tree; the storefront swallowed the error and lost every category (CAT-2). Tree mode: a node whose parent is not visible (inactive or deleted) is dropped together with its subtree, so deactivating a middle level hides what hangs below it. Flat mode keeps every active category; each item still carries its visible children, as before. ## OpenAPI ````yaml https://api.vellaro.io/openapi/storefront.json get /api/v1/categories openapi: 3.1.0 info: title: Vellaro Storefront API description: >- The API of storefronts and mobile apps. The store comes from the publishable key in the `X-Vellaro-Key` header (or from the store's domain); the customer's endpoints also take the customer's token as `Authorization: Bearer `. version: 0.1.0 servers: - url: https://api.vellaro.io description: Produzione security: [] tags: - name: Authentication description: >- Customer sign-up and login, tokens, password reset, email verification, Google and Apple login, two-factor authentication. - name: Catalog description: Products, categories and brands, with filters, sorting and pagination. - name: Search description: Full-text product search and suggestions as you type. - name: Cart description: >- The cart of a guest (`X-Cart-Token`) or of the logged-in customer, and the extra warranty offered on a product page. - name: Checkout & orders description: >- Checkout, the customer's orders and reorder, «Order on WhatsApp» (cart codes, clicks). - name: Payments description: >- The store's payment methods, paying an order again, and the confirmation steps of PayPal, PokPay and Iute. - name: Account description: >- The logged-in customer: profile, addresses, wishlist, digital downloads, subscriptions, affiliate account. - name: Reviews & questions description: Product reviews and product questions. - name: AI chat description: 'The store''s AI shopping assistant: conversations, messages, feedback.' - name: Content description: CMS pages, menus, banners, flipbooks and information pages. - name: Marketing & contact description: >- Newsletter sign-up and email links, the contact form, campaign click tracking. - name: Store description: >- The store for the storefront: brand, public settings, languages, translations, currencies, physical stores, theme. - name: Devices description: Push-notification devices of the mobile app. paths: /api/v1/categories: get: tags: - Catalog summary: List Categories description: >- Return all active categories — flat or nested tree. The tree is assembled in Python from ONE flat query (active, not soft-deleted), like `admin_list_categories`. The old version validated the ORM rows recursively over `selectinload(Category.children)`: that relation is unfiltered, so a deleted/inactive child came along, and its own (unloaded) children → MissingGreenlet → 500 on the whole public tree; the storefront swallowed the error and lost every category (CAT-2). Tree mode: a node whose parent is not visible (inactive or deleted) is dropped together with its subtree, so deactivating a middle level hides what hangs below it. Flat mode keeps every active category; each item still carries its visible children, as before. operationId: list_categories_api_v1_categories_get parameters: - name: tree in: query required: false schema: type: boolean description: Return as nested tree default: true title: Tree description: Return as nested tree - name: lang in: query required: false schema: anyOf: - type: string - type: 'null' description: Force content language (it|en|sq) title: Lang description: Force content language (it|en|sq) responses: '200': description: Successful Response content: application/json: schema: $ref: '#/components/schemas/ApiResponse_list_CategoryOut__' '422': description: Validation Error content: application/json: schema: $ref: '#/components/schemas/HTTPValidationError' components: schemas: ApiResponse_list_CategoryOut__: properties: data: anyOf: - items: $ref: >- #/components/schemas/app__modules__products__schemas__CategoryOut type: array - type: 'null' title: Data meta: anyOf: - $ref: '#/components/schemas/PaginationMeta' - type: 'null' error: anyOf: - type: string - type: 'null' title: Error error_code: anyOf: - type: string - type: 'null' title: Error Code type: object title: ApiResponse[list[CategoryOut]] HTTPValidationError: properties: detail: items: $ref: '#/components/schemas/ValidationError' type: array title: Detail type: object title: HTTPValidationError app__modules__products__schemas__CategoryOut: properties: id: type: string format: uuid title: Id name: type: string title: Name name_i18n: anyOf: - additionalProperties: true type: object - type: 'null' title: Name I18N slug: type: string title: Slug description: anyOf: - type: string - type: 'null' title: Description description_i18n: anyOf: - additionalProperties: true type: object - type: 'null' title: Description I18N image_url: anyOf: - type: string - type: 'null' title: Image Url parent_id: anyOf: - type: string format: uuid - type: 'null' title: Parent Id position: type: integer title: Position is_active: type: boolean title: Is Active children: items: $ref: '#/components/schemas/app__modules__products__schemas__CategoryOut' type: array title: Children default: [] type: object required: - id - name - slug - description - image_url - parent_id - position - is_active title: CategoryOut PaginationMeta: properties: page: type: integer title: Page page_size: type: integer title: Page Size total: type: integer title: Total total_pages: type: integer title: Total Pages type: object required: - page - page_size - total - total_pages title: PaginationMeta ValidationError: properties: loc: items: anyOf: - type: string - type: integer type: array title: Location msg: type: string title: Message type: type: string title: Error Type input: title: Input ctx: type: object title: Context type: object required: - loc - msg - type title: ValidationError ```` This documentation is built and hosted on [Mintlify](https://mintlify.com), a developer documentation platform.