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# Overview

## Customers — Base: `/v1/customers`

**Customers** are the **merchant's clients** (the buyers), stored per store. They hold contact and address details (`name` and `email` required; phone and address optional).

Their main use: they are the recipients to whom the merchant **extends payment requests of type** **`INVOICE`** — bills issued to a specific customer that the customer later pays through a *checkout invoice* generated at checkout. An invoice's `customerId` points to one of these records.

* **Uniqueness**: `email` is unique per store (case-insensitive); a duplicate email returns `400`.

* **Scope (store)**: `storeId` is derived from the API key context; it is not sent in the body.

* **Scopes**: `Merchant.customer.{read,create,update,delete}`.

Endpoints: create, list, get by id, update and delete a customer.