Your sandbox patients
A small roster fetched live from your own sandbox — GET /fhir/R4/Patient?_count=5, then a follow-up read per patient for how many appointments, encounters, and observations they carry. Pin one of these ids into a recipe instead of guessing at an example id that won't exist in your organization.
No sandbox token set
Get one from the "Open the playground" link on your key-reveal page, or paste a sandbox token here. Never a production key — sandbox keys are verified before they're saved, and a production key is rejected. Once verified, it's stored in sessionStorage on this origin and sent with every request this page runs. See Sandbox quickstart if you don't have one yet.
Set a verified sandbox token above, then load the roster.