A token is a reference to a stored payment credential held by the processor. It lets a platform bill a returning patient without ever handling the raw card number, which is both a security control and a PCI scope reduction.
Tokens are also the single most important asset in a subscription telehealth business, and the least discussed. Whoever holds them holds the ability to keep billing your patients.
Token portability is the question that decides what leaving a platform actually costs. Processors can migrate tokens between accounts, but only when the holding party agrees to release them.
Without token portability, migration means a mass re-collection of payment details from every active subscriber. Realistic response rates make this the largest single cost of switching platforms, and it never appears on an invoice.
Card tokenization, in practice
On PharmaBro, yes, within 24 hours of asking, because the Stripe account is already yours. On platforms that act as merchant of record, this depends entirely on their willingness to release them, so get the answer in writing before you sign rather than when you leave.