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

> ## Agent Instructions
> Automate.ax automations are TypeScript programs.
> Use Bun for installation and command examples.
> Use Automate.ax for the product name and automate.ax for the package, CLI, and domain.
> Treat documented public APIs as current; do not invent transitional or deprecated names.

# Retrieve Merchant Custom Attribute Definition

> Retrieves a merchant-related [custom attribute definition](entity:CustomAttributeDefinition) from a Square seller account.

`square.retrieveMerchantCustomAttributeDefinition` retrieves a merchant-related [custom attribute definition](entity:CustomAttributeDefinition) from a Square seller account.

## Example

```ts automations/square-retrieve-merchant-custom-attribute-definition.automation.ts theme={null}
import { automation, onDashboardRun } from "automate.ax"
import { square } from "automate.ax/square"

export default automation(
  "Retrieve Square Merchant Custom Attribute Definition",
  () => {
    onDashboardRun({
      title: "Retrieve Square Merchant Custom Attribute Definition",
    })

    square.retrieveMerchantCustomAttributeDefinition({
      key: "key",
      version: 1,
    })
  },
)
```

## Inputs

Every input accepts a compatible signal. It requires `MERCHANT_PROFILE_READ`.

| Field     | Type             | Required | Default | Description                                                                                                                                                                                                                                                                                                                                                          |
| --------- | ---------------- | -------- | ------- | -------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| `key`     | `string`         | Yes      | —       | The key of the custom attribute definition to retrieve. If the requesting application is not the definition owner, you must use the qualified key.                                                                                                                                                                                                                   |
| `version` | `number \| null` | No       | —       | The current version of the custom attribute definition, which is used for strongly consistent reads to guarantee that you receive the most up-to-date data. When included in the request, Square returns the specified version or a higher version if one exists. If the specified version is higher than the current version, Square returns a `BAD_REQUEST` error. |

Use the official [RetrieveMerchantCustomAttributeDefinition reference](https://developer.squareup.com/reference/square/merchant-custom-attributes-api/retrieve-merchant-custom-attribute-definition) for provider field semantics and limits.

## Output

Returns the official `Square.RetrieveMerchantCustomAttributeDefinitionResponse` response as a codec-safe object. Square integer money amounts remain `bigint` values.