Use cases

What you verify is set when your backend creates the session, with its purpose. The SDK then runs exactly the steps that purpose requires.

Customer onboarding

The full check for opening an account or wallet: the customer photographs their identity document, completes a short liveness check, and Blink compares their face with the document photo. Use FULL_CAPTURE — the default when no purpose is sent.

Document verification

Check an identity document on its own, for example when a customer updates an expired ID. Use DOCUMENT_VERIFICATION. No selfie is taken.

Liveness only

Confirm that a real person is present, without a document — for example before a sensitive action by a customer you already know. Use LIVENESS.

Face match

Confirm that the person holding the document is its owner. Use FACE_MATCH; it captures the document and the selfie, then compares the two faces.

Which steps each purpose runs

The document step always runs before liveness. A step outside the session's purpose is refused with BLINK_STEP_NOT_IN_PURPOSE.

Supported documents

Which countries and document types are offered to a customer comes from your client's configuration; the SDK can show Blink's country and document chooser when you don't fix a type yourself.

The three decisions