Execute the Da Vinci PDex $member-match operation to identify a member across payer systems during payer-to-payer exchange

Verified steps

1. Review the Da Vinci PDex $member-match operation specification to understand the input Parameters resource structure, which includes the member's demographic data (as a FHIR Patient) and prior coverage information (as a FHIR Coverage).
2. Construct the $member-match Parameters resource with the MemberPatient parameter (patient demographics), CoverageToMatch parameter (prior payer's Coverage resource with member ID and payer information), and optionally CoverageToLink (new payer's Coverage).
3. POST the Parameters resource to [base]/Patient/$member-match on the prior payer's FHIR endpoint using backend-services or appropriate B2B authentication.
4. Parse the response: a successful match returns a Parameters resource containing a single Patient resource (with the prior payer's member identifier) and optionally updated Coverage details.
5. Handle non-match responses: the operation returns an HTTP 422 with OperationOutcome if no match is found or if multiple ambiguous matches exist — implement logic to handle each error code defined in the PDex IG.
6. Use the matched member identifier from the response to request the member's clinical and claims data via subsequent PDex data exchange operations or bulk data requests.