Recognise returning visitors through the SDK

Pass your own user identifier when opening an agent and Handhold recognises the visitor when they come back, on any device or browser.

• Pick up where they left off. Returning visitors get their start screen prefilled and the agent remembers previous conversations, so nobody restarts from zero.
• Works across devices. Recognition no longer depends on the visitor's browser storage. The same identifier means the same visitor, whether they return on a laptop, a phone or a cleared browser.
• One line of integration. Add externalVisitorId to your openDemo call with an identifier your product already knows.

Security note: the identifier is a credential. Anyone who presents it is treated as that visitor, sees their previously shared answers and can continue their conversations. Use an opaque, unguessable value, never an email address or a sequential number, and only pass it on pages where the visitor is signed in. The API reference has the details.