<OperationOutcome xmlns="http://hl7.org/fhir">
  <id value="operationoutcome-example-merge-error" />
  <meta>
    <profile value="http://ontariohealth.ca/fhir/pcr/StructureDefinition/pcr-operationoutcome-contribution" />
  </meta>
  <issue>
    <severity value="error" />
    <code value="required" />
    <details>
      <text value="Both source-patient and target-patient are required for a merge request." />
    </details>
    <expression value="Parameters.parameter.where(name = 'source-patient')" />
    <expression value="Parameters.parameter.where(name = 'target-patient')" />
  </issue>
</OperationOutcome>