> For the complete documentation index, see [llms.txt](https://help.inveterate.com/dev/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://help.inveterate.com/dev/api-reference-docs/legacy-public-api-reference/free-tiers-api.md).

# Free tiers API

To sign up for free tier membership, customer has to be registered in Shopify. 

```typescript
{
    merchantId: string,
    customerId: string,
    segmentId: string?,
}
```

## Sign up customer for free tier

<mark style="color:green;">`POST`</mark> `https://public.inveterateapi.com/signup-free-tier`

#### Request Body

| Name                                         | Type   | Description                                                                                                                                                      |
| -------------------------------------------- | ------ | ---------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| merchantId<mark style="color:red;">\*</mark> | String | merchantId is the first part of the shop domain. For example if the shop domain is **inveterate-demo.myshopify.com**, Merchant ID is **inveterate-demo**         |
| customerId<mark style="color:red;">\*</mark> | String | Shopify legacy customer IDs with numerical values such as "6412233234" are supported. GraphQL IDs such as  "gid://shopify/Customer/6412233234" are not supported |
| segmentId                                    | String | Optionally provided to specify which free tier the customer is to be enrolled into. If absent, the first free tier to be created is assumed.                     |

{% tabs %}
{% tab title="202: Accepted Successful response" %}

{% endtab %}

{% tab title="400: Bad Request Required body parameters are missing" %}

{% endtab %}

{% tab title="403: Forbidden Free tier is not enabled for the merchant" %}

{% endtab %}
{% endtabs %}


---

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