Define Custom Attributes for Merchants

Applies to: Merchant Custom Attributes API

Learn how to define merchant-related custom attributes for Square sellers using the Merchant Custom Attributes API.

A custom attribute definition specifies the key identifier, the visibility setting, the schema data type, and other properties for a custom attribute. After the definition is created, an associated custom attribute can be created and assigned to a merchant. For more information about how merchant-related custom attributes work, see Custom Attributes for Merchants.

A custom attribute definition is represented by a CustomAttributeDefinition object. The following is an example custom attribute definition that defines a "charity" custom attribute of the Boolean data type:

{
  "custom_attribute_definition": {
    "key": "charity",
    "name": "Charitable Organization",
    "description": "Is this merchant a charitable organization with 501(c)(3) status?",
    "version": 1,
    "updated_at": "2023-01-20T02:41:37Z",
    "schema": {
      "$ref": "https://developer-production-s.squarecdn.com/schemas/v1/common.json#squareup.common.Boolean"
    },
    "created_at": "2023-01-20T02:41:37Z",
    "visibility": "VISIBILITY_READ_WRITE_VALUES"
  }
}

The following fields represent core properties of a custom attribute definition:

Use the CreateMerchantCustomAttributeDefinition endpoint to create a custom attribute definition for a seller account. This operation makes the custom attribute available to that merchant.

The following request creates a custom attribute definition to represent the name of a merchant's business owner. The schema field indicates that the value of the custom attribute is a String.

The following is an example response:

{
  "custom_attribute_definition": {
    "key": "business-owner",
    "name": "Business Owner",
    "description": "The name of the business owner",
    "version": 1,
    "updated_at": "2023-01-20T02:41:37Z",
    "schema": {
      "$ref": "https://developer-production-s.squarecdn.com/schemas/v1/common.json#squareup.common.String"
    },
    "created_at": "2023-01-20T02:41:37Z",
    "visibility": "VISIBILITY_READ_WRITE_VALUES"
  }
}

Now that the custom attribute definition is created, you can set the custom attribute for the merchant individually or in bulk.

After a custom attribute definition is created, Square invokes the merchant.custom_attribute_definition.owned.created and merchant.custom_attribute_definition.visible.created webhooks.

A seller account can have a maximum of 100 merchant-related custom attribute definitions per application.

For a Selection data type, the schema contains a $schema field that references a JSON meta-schema object, as well as additional fields. Note the following:

• $schema references the https://developer-production-s.squarecdn.com/meta-schemas/v1/selection.json meta-schema hosted on the Square CDN.
• type must be array.
• items must include a names array that contains strings representing the display names of the predefined options that can be selected. Note that the order of the options might not be respected by all UIs.
• maxItems is an integer that represents the maximum number of allowed selections. Corresponding custom attributes can have zero or more selected values, up to the specified maximum. The minimum value is 1 and cannot exceed the number of options in the names field.
• uniqueItems must be true.

The following example request creates a Selection-type custom attribute definition that contains six named options and allows for a selection of all six:

The following is an example response. For each named option, Square generates a UUID and adds it to the enum field. The options in the names field map by index to the UUIDs in the enum field. The first option maps to the first UUID, the second option maps to the second UUID, and so on.

These UUIDs are used to set the value of the custom attribute or update the option names.

{
    "custom_attribute_definition": {
      "key": "diversity-label",
      "name": "Diversity label",
      "description": "The self-reported diversity label(s) for the business",
        "version": 1,
        "updated_at": "2022-12-06T15:57:23.211Z",
        "schema": {
            "$schema": "https://developer-production-s.squarecdn.com/meta-schemas/v1/selection.json",
            "maxItems": 3.0,
            "type": "array",
            "uniqueItems": true,
            "items": {
                "names": [
                    "Woman-owned",
                    "Black-owned",
                    "Asian-owned",
                    "Indigenous-owned",
                    "LGBTQ+ owned",
                    "Veteran-owned"
                ],
                "enum": [
                    "46efa55a-1f1d-467f-9733-468f881a4f20",
                    "954998e1-b666-43a4-baf3-89cb87afe25a",
                    "610fa590-70cd-4ec9-b64c-1dad6ba3c8f9",
                    "92ds8kzp-44tz-38d7-vjsg-rj35apkvg5vt",
                    "2jrxqv8l-9pcn-adfg-g35u-65yi30ref2od",
                    "b2f3cfed-c884-4621-9a16-c24932480c24"
                ]
            }
        },
        "created_at": "2022-12-06T15:57:23.211Z",
        "visibility": "VISIBILITY_READ_ONLY"
    }
}

Use the UpdateMerchantCustomAttributeDefinition endpoint to update a custom attribute definition for a seller account. The endpoint supports sparse updates, so only new or changed fields need to be included in the request. Only the following fields can be updated:

• name
• description
• visibility
• schema for a Selection data type

Note the following about an UpdateMerchantCustomAttributeDefinition request:

• A custom attribute definition can only be updated by the definition owner.
• The key path parameter is the key of the custom attribute definition.
• The version field must match the current version of the custom attribute definition to enable optimistic concurrency control. If this isn't important for your application, version can be set to –1. For any other values, the request fails with a BAD_REQUEST error. Square increments the version number each time the definition is updated.
• The idempotency_key is a unique ID for the request that can be optionally included to ensure idempotency.
• Changes to the visibility setting are propagated to corresponding custom attributes within a few seconds. At that time, the updated_at and version fields of the custom attributes are also updated. For VISIBILITY_READ_ONLY or VISIBILITY_READ_WRITE_VALUES settings, the definition must have both a name and a description.

The following request updates the visibility setting of a definition:

The following is an example response:

{
  "custom_attribute_definition": {
    "key": "business-owner",
    "name": "Business Owner",
    "description": "The name of the business owner",
    "version": 2,
    "updated_at": "2023-02-02T04:17:09Z",
    "schema": {
      "$ref": "https://developer-production-s.squarecdn.com/schemas/v1/common.json#squareup.common.String"
    },
    "created_at": "2023-01-20T02:41:37Z",
    "visibility": "VISIBILITY_READ_ONLY"
  }
}

After a merchant-related custom attribute definition is updated, Square invokes the merchant.custom_attribute_definition.owned.updated and merchant.custom_attribute_definition.visible.updated webhooks.

For a Selection data type, you can update the maximum number of allowed selections and the set of predefined named options.

The information you send in the UpdateMerchantCustomAttributeDefinition request depends on the change you want to make:

• To change the maximum number of allowed selections, include the maxItems field with the new integer value. The minimum value is 1 and cannot exceed the number of options in the names field.
• To change the set of predefined named options, include the items field with the complete names and enum arrays. The options in the names array map by index to the Square-assigned UUIDs in the enum array, which are unique per seller. The first option maps to the first UUID, the second option maps to the second UUID, and so on.
  • To add an option:
    • Add the name of the new option at the end of the names array. New options must always be added to the end of the array.
    • Don't change the enum array. Square generates a UUID for the new option and adds it to the end of the enum array.
  • To reorder the options:

    • Change the order of the names in the names array.

    • Change the order of the UUIDs in the enum array so that the order of the UUIDs matches the order of the corresponding named options.

      Note that the order might not be respected by all UIs.

  • To remove an option:
    • Remove the name of the option from the names array.
    • Remove the corresponding UUID from the enum array.

The following UpdateMerchantCustomAttributeDefinition request adds two new options by adding their names at the end of the names array:

The following example response includes the UUIDs that Square generated for the new Furniture consignment and Rug cleaning options:

{
    "custom_attribute_definition": {
        "key": "diversity-label",
        "name": "Diversity label",
        "description": "The self-reported diversity label(s) for the business",
        "version": 2,
        "updated_at": "2023-01-09T15:57:23.211Z",
        "schema": {
            "$schema": "https://developer-production-s.squarecdn.com/meta-schemas/v1/selection.json",
            "maxItems": 8.0,
            "type": "array",
            "uniqueItems": true,
            "items": {
                "names": [
                    "Woman-owned",
                    "Black-owned",
                    "Asian-owned",
                    "Indigenous-owned",
                    "LGBTQ+ owned",
                    "Veteran-owned",
                    "Latin-owned",
                    "Pacific Islander-owned"
                ],
                "enum": [
                    "46efa55a-1f1d-467f-9733-468f881a4f20",
                    "954998e1-b666-43a4-baf3-89cb87afe25a",
                    "610fa590-70cd-4ec9-b64c-1dad6ba3c8f9",
                    "92ds8kzp-44tz-38d7-vjsg-rj35apkvg5vt",
                    "2jrxqv8l-9pcn-adfg-g35u-65yi30ref2od",
                    "b2f3cfed-c884-4621-9a16-c24932480c24",
                    "6etk4juf-q3px-44jm-b7zp-vpwkv89dsok2",
                    "46y4hveq-s4c5-7zvt-cyrb-2ferha95fvlv"
                ]
            }
        },
        "created_at": "2022-12-06T15:57:23.211Z",
        "visibility": "VISIBILITY_READ_ONLY"
    }
}

Use the ListMerchantCustomAttributeDefinitions endpoint to list the custom attribute definitions from a seller account.

The limit query parameter optionally specifies a maximum page size of 100 results. The default limit is 20 results. If the results are paged, the cursor field in the response contains a value that you can send with the cursor query parameter to retrieve the next page of results.

The following example request includes the limit query parameter:

When all pages are retrieved, all custom attribute definitions created by the requesting application are included in the results. The key for these definitions is the key value that was provided when the definition was created.

Custom attribute definitions created by other applications are included if their visibility setting is VISIBILITY_READ_ONLY or VISIBILITY_READ_WRITE_VALUES.

The following is an example response containing four custom attribute definitions:

{
    "custom_attribute_definitions": [
        {
             "key": "business-owner",
            "name": "Business Owner",
            "description": "The name of the business owner",
    		"version": 2,
    		"updated_at": "2023-02-02T04:17:09Z",
    		"schema": {
      		    "$ref": "https://developer-production-s.squarecdn.com/schemas/v1/common.json#squareup.common.String"
    },
    		"created_at": "2023-01-20T02:41:37Z",
    		"visibility": "VISIBILITY_READ_ONLY"
        },
        {
             "key": "owner-email",
    		"name": "Business Owner Email",
    		"description": "The email address of the business owner",
    		"version": 1,
    		"updated_at": "2023-01-20T02:41:37Z",
    		"schema": {
     			 "$ref": "https://developer-production-s.squarecdn.com/schemas/v1/common.json#squareup.common.Email"
    	},
    		"created_at": "2023-01-20T02:41:37Z",
    		"visibility": "VISIBILITY_HIDDEN"
        },
        {
            "key": "employees",
            "name": "Number of employees",
            "description": "The number of full-time employees of this merchant",
            "version": 1,
            "updated_at": "2022-12-02T19:51:29.235Z",
            "schema": {
                "$ref": "https://developer-production-s.squarecdn.com/schemas/v1/common.json#squareup.common.Number"
            },
            "created_at": "2022-12-02T19:51:29.235Z",
            "visibility": "VISIBILITY_READ_WRITE_VALUES"
        },
        {
             "key": "diversity-label",
            "name": "Diversity label",
            "description": "The self-reported diversity label(s) for the business",
            "version": 2,
            "updated_at": "2022-12-06T15:57:23.211Z",
            "schema": {
                "$schema": "https://developer-production-s.squarecdn.com/meta-schemas/v1/selection.json",
                "maxItems": 8.0,
                "type": "array",
                "uniqueItems": true,
                "items": {
                     "names": [
                    "Woman-owned",
                    "Black-owned",
                    "Asian-owned",
                    "Indigenous-owned",
                    "LGBTQ+ owned",
                    "Veteran-owned",
                    "Latin-owned",
                    "Pacific Islander-owned"
                ],
                    "enum": [
                    "46efa55a-1f1d-467f-9733-468f881a4f20",
                    "954998e1-b666-43a4-baf3-89cb87afe25a",
                    "610fa590-70cd-4ec9-b64c-1dad6ba3c8f9",
                    "92ds8kzp-44tz-38d7-vjsg-rj35apkvg5vt",
                    "2jrxqv8l-9pcn-adfg-g35u-65yi30ref2od",
                    "b2f3cfed-c884-4621-9a16-c24932480c24",
                    "6etk4juf-q3px-44jm-b7zp-vpwkv89dsok2",
                    "46y4hveq-s4c5-7zvt-cyrb-2ferha95fvlv"
                ]
                }
            },
            "created_at": "2022-12-06T15:57:23.211Z",
        	"visibility": "VISIBILITY_READ_ONLY"
        }
    ]
}

Note that the "Business Owner" and "Business Owner email" custom attribute definitions were created by the requesting application. Because "Business Owner email" is set to VISIBILITY_HIDDEN, it is returned only when requested by the definition owner.

If no custom attribute definitions are found, Square returns an empty response.

{}

Use the RetrieveMerchantCustomAttributeDefinition endpoint to retrieve a custom attribute definition using its key. Note the following:

• The key path parameter is the key value of the custom attribute definition.
• The version query parameter 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 later version if one exists. If the specified version is later than the current version, Square returns a 400 BAD_REQUEST error.

The following is an example request:

The following is an example response:

{
  "custom_attribute_definition": {
    "key": "business-owner",
    "name": "Business Owner",
    "description": "The name of the business owner",
    "version": 2,
    "updated_at": "2023-02-02T04:17:09Z",
    "schema": {
      "$ref": "https://developer-production-s.squarecdn.com/schemas/v1/common.json#squareup.common.String"
    },
    "created_at": "2023-01-20T02:41:37Z",
    "visibility": "VISIBILITY_READ_ONLY"
  }
}

If the custom attribute definition isn't found, Square returns an errors field that contains a 404 NOT_FOUND error.

Use the DeleteMerchantCustomAttributeDefinition endpoint to delete a custom attribute definition from a seller account. Note the following:

• Only the definition owner can delete a custom attribute definition.
• The key path parameter is the key value of the custom attribute definition.
• Deleting a custom attribute definition also deletes the corresponding custom attribute from all merchants on which it has been set.

The following is an example request:

If successful, Square returns an empty object.

{}

After a custom attribute definition is deleted, Square invokes the merchant.custom_attribute_definition.owned.deleted and merchant.custom_attribute_definition.visible.deleted webhooks.