
{
  "@context": "https://www.w3.org/ns/activitystreams",
  "summary": "Sally retracted her offer to John",
  "type": "Undo",
  "actor": "http://sally.example.org",
  "object": {
    "type": "Offer",
    "actor": "http://sally.example.org",
    "object": "http://example.org/posts/1",
    "target": "http://john.example.org"
  }
}
  