{

"resourceType": "SearchParameter",
"id": "example-extension",
"text": {
  "status": "generated",
  "div": "<div xmlns=\"http://www.w3.org/1999/xhtml\"><p><b>Generated Narrative with Details</b></p><p><b>id</b>: example-extension</p><p><b>url</b>: <a>http://hl7.org/fhir/SearchParameter/example-extension</a></p><p><b>name</b>: Example Search Parameter on an extension</p><p><b>status</b>: draft</p><p><b>experimental</b>: true</p><p><b>publisher</b>: Health Level Seven International (FHIR Infrastructure)</p><p><b>contact</b>: </p><p><b>code</b>: part-agree</p><p><b>base</b>: Patient</p><p><b>type</b>: reference</p><p><b>description</b>: Search by url for a participation agreement, which is stored in a DocumentReference</p><p><b>expression</b>: DocumentReference.extension('http://example.org/fhir/StructureDefinition/participation-agreement')</p><p><b>xpath</b>: f:DocumentReference/f:extension[@url='http://example.org/fhir/StructureDefinition/participation-agreement']</p><p><b>xpathUsage</b>: normal</p><p><b>target</b>: DocumentReference</p></div>"
},
"url": "http://hl7.org/fhir/SearchParameter/example-extension",
"name": "Example Search Parameter on an extension",
"status": "draft",
"experimental": true,
"publisher": "Health Level Seven International (FHIR Infrastructure)",
"contact": [
  {
    "telecom": [
      {
        "system": "url",
        "value": "http://hl7.org/fhir"
      }
    ]
  }
],
"code": "part-agree",
"base": [
  "Patient"
],
"type": "reference",
"description": "Search by url for a participation agreement, which is stored in a DocumentReference",
"expression": "DocumentReference.extension('http://example.org/fhir/StructureDefinition/participation-agreement')",
"xpath": "f:DocumentReference/f:extension[@url='http://example.org/fhir/StructureDefinition/participation-agreement']",
"xpathUsage": "normal",
"target": [
  "DocumentReference"
]

}