> ## Documentation Index > Fetch the complete documentation index at: https://developers.appstle.com/llms.txt > Use this file to discover all available pages before exploring further. # Add products or variants to an existing subscription group (async) > Same JSON body as the v2 bulk-add-products endpoint, but returns immediately with a 202 and processes the update in the background via an AWS Step Function worker instead of within the HTTP request. Use this for large batches (hundreds to thousands of IDs) that would otherwise risk hitting request/gateway timeouts. Poll GET /api/external/v2/subscription-groups/v3/{id}/add-products/status to check progress. Only one such job may run per shop at a time; a second request while one is in progress is rejected with a 400. **Authentication:** Requires valid X-API-Key header ## OpenAPI ````yaml /subscription/admin-api-swagger.json post /api/external/v2/subscription-groups/v3/{id}/add-products openapi: 3.0.1 info: description: >- Comprehensive API documentation for managing subscriptions, payments, and related operations. These APIs allow you to programmatically manage subscription lifecycles, handle payments, configure products, and integrate subscription functionality into your applications. title: Admin APIs version: 0.0.1 servers: - url: https://subscription-admin.appstle.com security: [] tags: - description: >- Core APIs for managing the complete subscription lifecycle including creation, updates, pausing, resuming, and cancellation of subscriptions. name: Subscription Management - description: >- APIs for managing subscription payment methods, processing payments, handling payment retries, and updating billing information. name: Subscription Payments - description: >- APIs for managing subscription contracts including delivery schedules, pricing, order notes, billing cycles, and shipping addresses. name: Subscription Contracts - description: >- APIs for managing products within subscriptions including adding, removing, updating quantities, and swapping products. name: Subscription Products - description: >- APIs for handling billing operations, payment processing, and financial transactions related to subscriptions. name: Billing & Payments - description: >- APIs for managing discounts and promotional codes applied to subscriptions. name: Subscription Discounts - description: >- APIs for managing one-time add-on products that can be purchased alongside recurring subscription items. name: Subscription One-Time Products - description: >- APIs for managing subscription plans, pricing tiers, and plan configurations. name: Subscription Plans - description: >- APIs for managing customizable product boxes and bundles where customers can select multiple items. name: Build-a-Box & Bundles - description: >- APIs for managing the product catalog including product information, variants, and inventory. name: Product Catalog - description: >- APIs for managing operational settings, configurations, and administrative functions. name: Operations & Settings - description: >- APIs powering the customer-facing portal where subscribers can manage their own subscriptions. name: Customer Portal - description: APIs for managing customer information, profiles, and account details. name: Customers - description: >- APIs for retrieving aggregated subscription data, customer subscription history, and account-level subscription information. name: Subscription Data - description: >- APIs for managing delivery profiles, shipping rates, free shipping configuration, and delivery method options on subscriptions. name: Delivery & Shipping - description: >- APIs for managing storefront customization including custom CSS, theme settings, label translations, and merchant-defined widget configuration. name: Customization - description: >- APIs for configuring cancellation flows, retention offers, cancellation reason management, and win-back automation. name: Customer Retention paths: /api/external/v2/subscription-groups/v3/{id}/add-products: post: tags: - Subscription Plans summary: Add products or variants to an existing subscription group (async) description: >- Same JSON body as the v2 bulk-add-products endpoint, but returns immediately with a 202 and processes the update in the background via an AWS Step Function worker instead of within the HTTP request. Use this for large batches (hundreds to thousands of IDs) that would otherwise risk hitting request/gateway timeouts. Poll GET /api/external/v2/subscription-groups/v3/{id}/add-products/status to check progress. Only one such job may run per shop at a time; a second request while one is in progress is rejected with a 400. **Authentication:** Requires valid X-API-Key header operationId: addProductsOrVariantsAsync parameters: - description: Subscription group ID (numeric ID) example: 123456789 in: path name: id required: true schema: format: int64 type: integer - deprecated: true description: API Key (Deprecated - Use X-API-Key header instead) in: query name: api_key required: false schema: type: string - description: API Key for authentication example: sk_live_1234567890abcdef in: header name: X-API-Key required: true schema: type: string requestBody: content: application/json: schema: $ref: '#/components/schemas/BulkAddProductsRequest' description: Product and variant IDs to add to the subscription group required: true responses: '202': content: '*/*': schema: type: object description: Job accepted and started in the background '400': content: '*/*': schema: type: object description: Invalid request, or a job for this shop is already in progress '401': content: '*/*': schema: type: object description: Authentication required - missing or invalid API key '404': content: '*/*': schema: type: object description: Subscription group not found components: schemas: BulkAddProductsRequest: properties: productIds: items: format: int64 type: integer type: array variantIds: items: format: int64 type: integer type: array type: object ````