This is one of many protocol behaviors described in ActivityPub.

Identifier

urn:uuid:f965e989-4084-4f9d-9119-6a7ea13bcb64

Content

The likes collection MUST be either an OrderedCollection or a Collection

Origin

prefix Every object MAY have a likes collection. This is a list of all Like activities with this object as the object property, added as a side effect.

The likes collection MUST be either an OrderedCollection or a Collection
 
suffix and MAY be filtered on privileges of an authenticated user or as appropriate when no authentication is given.

https://www.w3.org/TR/activitypub/

JSON

{
  "id": "urn:uuid:f965e989-4084-4f9d-9119-6a7ea13bcb64",
  "type": "Behavior",
  "uuid": "f965e989-4084-4f9d-9119-6a7ea13bcb64",
  "content": "The likes collection MUST be either an OrderedCollection or a Collection\n",
  "origin": {
    "source": "https://www.w3.org/TR/activitypub/",
    "section": {
      "id": "https://www.w3.org/TR/activitypub/#likes",
      "branch": [
        5,
        7
      ]
    },
    "selector": {
      "type": "TextQuoteSelector",
      "prefix": "Every object MAY have a likes collection. This is a list of all Like activities with this object as the object property, added as a side effect.\n",
      "exact": "The likes collection MUST be either an OrderedCollection or a Collection\n",
      "suffix": "and MAY be filtered on privileges of an authenticated user or as appropriate when no authentication is given.\n"
    }
  },
  "@context": [
    "https://www.w3.org/ns/activitystreams",
    "https://socialweb.coop/ns/testing/context.json"
  ]
}