> ## 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.

# Appstle Subscriptions: Recurring Revenue for Shopify

> Learn how Appstle Subscriptions works, when to use the Admin API vs. the Storefront API, and what you can build with each interface.

Appstle Subscriptions gives Shopify merchants a complete platform for selling and managing recurring products. Once you install the app, Shopify stores subscription contracts natively — and Appstle exposes two REST API surfaces so you can build integrations, automation workflows, custom portals, and more on top of that data.

## Available APIs

Appstle Subscriptions exposes two REST API surfaces. Pick the one that matches where your code runs:

* **Admin API** — server-side, authenticated with `X-API-Key`. For backend integrations, mobile apps, automation, and admin dashboards. Browse the full reference under **Admin API** in the sidebar.
* **Storefront API** — customer-facing, accessed through Shopify App Proxy. For custom subscription portals on your storefront. Browse the full reference under **Storefront API** in the sidebar.

## Which API should you use?

<Tabs>
  <Tab title="Use the Admin API when…">
    * You are building a **server-side integration** (backend service, CRM connector, helpdesk plugin)
    * You are building a **mobile app** (iOS or Android)
    * You need to **manage subscriptions programmatically** on behalf of merchants
    * You want to run **bulk operations** or scheduled automation
    * You are building an **admin dashboard** or reporting tool
    * Your code runs **anywhere outside a customer's browser** on the storefront

    <Info>
      Admin API requests require an `X-API-Key` header. Keys are created in the Appstle dashboard under **Settings → API Key Management**. Never expose keys in client-side code.
    </Info>
  </Tab>

  <Tab title="Use the Storefront API when…">
    * You are building a **custom customer portal** hosted on your Shopify storefront
    * You want customers to **self-manage their subscriptions** (skip, pause, swap products, update payment)
    * Your code runs **inside the storefront** with a logged-in customer session
    * You are customizing the subscription portal **theme or appearance**

    <Warning>
      Storefront APIs run exclusively through Shopify's App Proxy and require the customer to be logged in. They will not accept API key authentication and cannot be called from a backend server.
    </Warning>
  </Tab>
</Tabs>

## Key features

<CardGroup cols={2}>
  <Card title="Subscription management" icon="rotate">
    Create, update, pause, resume, and cancel subscription contracts. Full lifecycle control from initial checkout through cancellation.
  </Card>

  <Card title="Billing & payments" icon="credit-card">
    Process payments, handle billing failures, update payment methods, and manage billing cycles and retry logic.
  </Card>

  <Card title="Product catalog" icon="box">
    Configure subscription-eligible products, manage selling plans, handle product swaps, and set up Build-a-Box bundles.
  </Card>

  <Card title="Order fulfillment" icon="truck">
    Manage subscription order cycles, skip upcoming orders, reschedule billing dates, and control delivery schedules.
  </Card>

  <Card title="Reporting & analytics" icon="chart-bar">
    Access revenue metrics, billing history, order counts per subscription contract, and detailed past-order reports.
  </Card>

  <Card title="Loyalty & rewards" icon="star">
    Integrate loyalty programs that let customers earn and redeem points on their subscription orders.
  </Card>

  <Card title="Customization" icon="palette">
    Apply custom CSS, configure label translations, and manage theme settings for the storefront widget and customer portal.
  </Card>

  <Card title="Automation" icon="bolt">
    Connect with Shopify Flow, listen to JavaScript storefront events, and receive real-time webhook notifications.
  </Card>
</CardGroup>

## Base URL

All Admin API endpoints use:

```
https://subscription-admin.appstle.com/api/external/v2/
```

Storefront API endpoints are accessed through your store's Shopify App Proxy — no separate base URL is needed.

## HTTP status codes

All API responses use standard HTTP status codes.

| Code  | Meaning                                    |
| ----- | ------------------------------------------ |
| `200` | Success                                    |
| `201` | Resource created                           |
| `400` | Bad request — invalid parameters           |
| `401` | Unauthorized — missing or invalid API key  |
| `403` | Forbidden — key lacks required permissions |
| `404` | Not found                                  |
| `429` | Rate limit exceeded                        |
| `500` | Server error                               |

Error responses follow this shape:

```json theme={null}
{
  "error": "Unauthorized",
  "message": "Invalid API key provided",
  "status": 401
}
```

## Next steps

<CardGroup cols={2}>
  <Card title="Authentication" icon="key" href="/subscription/authentication">
    Create API keys and learn how to authenticate every request.
  </Card>

  <Card title="Quickstart" icon="rocket" href="/subscription/quickstart">
    Make your first API call in under five minutes.
  </Card>

  <Card title="Integration guide" icon="book" href="/subscription/integration-guide">
    End-to-end walkthrough covering the most common integration workflows.
  </Card>

  <Card title="Webhooks" icon="bell" href="/subscription/webhooks">
    Receive real-time event notifications when subscriptions change.
  </Card>
</CardGroup>