> ## Documentation Index
> Fetch the complete documentation index at: https://help.smile.io/llms.txt
> Use this file to discover all available pages before exploring further.

# Smile API overview

> Extend your loyalty program with custom experiences and developer tools.

Learn how the Smile API helps you extend your loyalty program through custom development. This article provides a high-level overview of API access and common use cases. All setup and implementation steps are covered in our developer documentation.

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  **Feature availability**: The Smile API is available to merchants on the **Plus** and **Enterprise** plans.
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## What is the Smile API?

The Smile API lets you extend and customize your Smile loyalty program beyond the default features available in **Smile Admin**, with support from a developer.

Using the API, you can:

* Build custom loyalty and rewards experiences for your storefront or external tools.
* Create [custom ways for customers to earn points](/en/articles/4036268-manage-custom-activity-types).
* Connect Smile with other tools your business uses.

## Who is this for?

The Smile API is best suited for:

* Merchants on the **Plus** or **Enterprise** plan who want to build custom loyalty experiences.
* Teams working with an in-house or external developer.

If you're not working with a developer, you can still use Smile's built-in features to run a complete loyalty program without using the API.

## What merchants should know

Before planning an API-based implementation, keep the following in mind:

* The Smile API is **not a no-code feature** and requires development work.
* API access is only available on the **Plus** and **Enterprise** plans.
* **Webhooks aren't available to merchants.**
* You must be using **Shopify or BigCommerce** as your eCommerce platform to build with the Smile API.

If you're unsure whether your use case requires the API, our support team can help guide you.

## Developer documentation

All technical implementation details—including endpoints, authentication, and code examples—are maintained in our developer documentation.

If you're working with a developer, refer to the developer docs for:

* API and SDK reference material.
* Front-end customization and custom activities.

👉 Visit the **[Smile developer documentation](https://dev.smile.io/)** to get started.