# Content Sync API

> Source: https://agilitycms.com/docs/developers/content-sync-api

The Content Sync API makes it easy to keep a content cache or copy of Agility content so it can be readily accessible to your digital solution without calling home to Agility.

## Use Cases

- You need to support an offline mode and access content without making an API call to Agility.
- You want to reduce the amount of REST API calls made to Agility.
- You want so synchronize content from the CMS to another system such Redis Cache.
- You are running a Server-Side Rendered (SSR)web app and you want to cache your content locally, reducing latency for retrieving content.
- You are using a Static Site Generator (SSG) and you don't want to have to re-source all of your content on each build.
- You have a client-side Single Page Application, and want to cache content in local storage in the browser.

## How it Works

The Sync API endpoint is part of the Content Fetch API and is available for all customers.

These are the general steps a developer would need to synchronize content from Agility CMS to another system.

**Step one**: Setup a Webhook in Agility so that you can be notified when changes to our CMS are made.

**Step two**: When a webhook request is received, make a call to the Sync API :

```
curl -X GET "https://api.aglty.io/4582b5fa-u/fetch/en-us/sync/items?syncToken=0&pageSize=500" -H "accept: application/json" -H "APIKey: xxxxxxxxxx"
```

Your first call to the API will have a `syncToken` of `0`. 

The above call will return all content from the CMS in a paginated manner (max 500 per request), and provide the next `syncToken` to use.

**Step three**: Save the results into a local filesystem, database, or Redis Cache

**Step four**: Continue to query to the Sync API until no results are returned or `syncToken=0`- this means you are up to date.

**Step five:** Store the last `syncToken` you had, so that the next time you call the API you'll get the content that has changed since your last `syncToken`

## Using a Sync SDK

Agility CMS provides a JS SDK to handle syncing and managing for your sync token as well as providing interfaces for storing and accessing previously synced content.

[Sync Content using the JS SDK](https://agilitycms.com/docs/javascript/content-sync-js-sdk)