Retrieve a single practitioner by ID

Returns the full practitioner record for the specified certifyPractitionerId. Use this when you have a known certifyPractitionerId and need the complete practitioner data object; to search across practitioners by name, NPI, or other attributes, use GET /practitioners instead, and for relationship data such as groups, networks, or locations, see the /relationships/* sub-resources. {id} is the certifyPractitionerId assigned at creation; include the X-PII-View: true header to receive PII fields, which requires the practitioner read:pii permission. Which fields are actually withheld or nulled when PII is not requested is decided entirely by the downstream data-access layer — api-layer only forwards the flag and enforces the permission gate. This response never includes an ssn field; the SSN is exposed only via GET /practitioners/{id}/ssn. terminationDate and terminationReason are present only if the practitioner has been terminated (e.g. via PUT /practitioners/terminate); absent otherwise.