We will replace the approach described in Search on Messaging to instead say: To perform a search with messaging that mirrors REST functionality, the message should leverage a Parameters instance with a standard parameter name of "url" and a valueString that corresponds to the search string that would typically be to the right of the base URL.  E.g. if in REST you would say http://someserver.org/fhir/Patient?name=joe , then the parameter would have a value of "Patient?name=joe". The 'event' in this case would be either "search-type" or "search-system" in the system http://hl7.org/fhir/restful-interaction.   (If "search-system" is used, the string would start with a "?" rather than " [resource] ?".)  Systems would indicate support for this search mechanism using their CapabilityStatement as they would any other messaging event.  If a system supports messaging search but not RESTful search, the means of describing any limitations on what resources, search parameters, qualifiers, etc. they support is not currently defined. Messaging interfaces may also choose to define alternative search mechanisms including query-by-example searches that pass in a partially completed resource, or that use a Parameters instance populated in other ways.