externalId as the stable mapping to the corresponding record in your system.
Individual customers
An individual requires onlytype. Include profile fields you already know, and add more only when the current capability or task needs them.
Create the customer with POST /v3/customers:
data.id as CUSTOMER_ID. See Individual onboarding for policy context.
Business customers
A business requiresbusiness.legalName. Create the business with the same operation:
data.id as CUSTOMER_ID. See Business onboarding for policy and document context.
Add business related parties
Add directors, owners, and other business participants when they are known or requested. This example creates a director withPOST /v3/customers/{customerId}/related-parties:
data.id as RELATED_PARTY_ID.
Read readiness from capabilities
A customer does not have a verification or readiness status in the API. Read the customer withGET /v3/customers/{customerId} for current profile data, then use capabilities and their openTaskIds to decide what the customer can do next.