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

# Idempotency

Creation operations to the Layer API are idempotent when an external ID is specified, such as the `external_id` field on a [Business](/api-reference/business/business) object. Others are indicated in the documentation. While these keys are not always required, use of idempotency keys is highly recommended whenever available.