Operation Definition

{
  "resourceType" : "OperationDefinition",
  "id" : "Resource-filter",
  "text" : {
    "status" : "extensions",
    "div" : "<div>!-- Snipped for Brevity --></div>"
  },
  "extension" : [{
    "url" : "http://hl7.org/fhir/StructureDefinition/structuredefinition-fmm",
    "valueInteger" : 0
  },
  {
    "url" : "http://hl7.org/fhir/StructureDefinition/structuredefinition-standards-status",
    "valueCode" : "trial-use"
  }],
  "url" : "http://hl7.org/fhir/OperationDefinition/Resource-filter",
  "version" : "5.0.0-ballot",
  "name" : "Filter",
  "title" : "Filter an array in a large resource",
  "status" : "draft",
  "kind" : "operation",
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  "date" : "2022-09-07T10:58:29+10:00",
  "publisher" : "HL7 (FHIR Project)",
  "contact" : [{
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      "value" : "http://hl7.org/fhir"
    },
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      "system" : "email",
      "value" : "fhir@lists.hl7.org"
    }]
  }],
  "description" : "Filter content from an array in a large resource such as List or Group. See [Operations for Large Resources](operations-for-large-resources.html).",
  "affectsState" : true,
  "code" : "filter",
  "resource" : ["Resource"],
  "system" : false,
  "type" : false,
  "instance" : true,
  "parameter" : [{
    "name" : "probes",
    "use" : "in",
    "min" : 1,
    "max" : "1",
    "documentation" : "Resource containing content that acts as a filter. See [Operations for Large Resources](operations-for-large-resources.html).",
    "type" : "Resource"
  },
  {
    "name" : "return",
    "use" : "out",
    "min" : 0,
    "max" : "1",
    "documentation" : "Resource containing content matching the filter. See [Operations for Large Resources](operations-for-large-resources.html).",
    "type" : "Resource"
  }]
}