Variations of inReplyTo

The property is defined here. The goal of this support table is to show how applications react to inReplyTo containing a wide variation of allowed objects. As Fediverse applications generally only give one the option to reply to a single element, the lacking support should not be surprising.

Examples

Example 1

activity

{
  "@context": [
    "https://www.w3.org/ns/activitystreams",
    {
      "Hashtag": "as:Hashtag",
      "sensitive": "as:sensitive"
    }
  ],
  "type": "Create",
  "actor": "http://pasture-one-actor/actor",
  "to": [
    "http://mastodon/users/hippo",
    "https://www.w3.org/ns/activitystreams#Public"
  ],
  "id": "http://pasture-one-actor/activity/hYLD6StMK2Q",
  "published": "2025-10-23T11:07:23Z",
  "object": {
    "type": "Note",
    "attributedTo": "http://pasture-one-actor/actor",
    "to": [
      "https://www.w3.org/ns/activitystreams#Public",
      "http://mastodon/users/hippo"
    ],
    "id": "http://pasture-one-actor/object/-waYXmn0vU0",
    "published": "2025-10-23T11:07:23Z",
    "content": "valid uri",
    "inReplyTo": "http://pasture-one-actor/assets/note1.jsonap"
  }
}

mastodon

{
  "id": "115423159499307397",
  "created_at": "2025-10-23T11:07:23.000Z",
  "in_reply_to_id": "111709172895877931",
  "in_reply_to_account_id": "115423154430999947",
  "sensitive": false,
  "spoiler_text": "",
  "visibility": "public",
  "language": null,
  "uri": "http://pasture-one-actor/object/-waYXmn0vU0",
  "url": "http://pasture-one-actor/object/-waYXmn0vU0",
  "replies_count": 0,
  "reblogs_count": 0,
  "favourites_count": 0,
  "edited_at": null,
  "favourited": false,
  "reblogged": false,
  "muted": false,
  "bookmarked": false,
  "content": "valid uri",
  "filtered": [],
  "reblog": null,
  "account": {
    "id": "115423154430999947",
    "username": "actor",
    "acct": "actor@pasture-one-actor",
    "display_name": "Test Actor",
    "locked": false,
    "bot": false,
    "discoverable": false,
    "indexable": false,
    "group": false,
    "created_at": "2025-10-23T00:00:00.000Z",
    "note": "",
    "url": "http://pasture-one-actor/actor",
    "uri": "http://pasture-one-actor/actor",
    "avatar": "http://mastodon/avatars/original/missing.png",
    "avatar_static": "http://mastodon/avatars/original/missing.png",
    "header": "http://mastodon/headers/original/missing.png",
    "header_static": "http://mastodon/headers/original/missing.png",
    "followers_count": 0,
    "following_count": 0,
    "statuses_count": 60,
    "last_status_at": "2025-10-23",
    "hide_collections": true,
    "emojis": [],
    "fields": []
  },
  "media_attachments": [],
  "mentions": [],
  "tags": [],
  "emojis": [],
  "quote": null,
  "card": null,
  "poll": null
}

Example 2

activity

{
  "@context": [
    "https://www.w3.org/ns/activitystreams",
    {
      "Hashtag": "as:Hashtag",
      "sensitive": "as:sensitive"
    }
  ],
  "type": "Create",
  "actor": "http://pasture-one-actor/actor",
  "to": [
    "http://mastodon/users/hippo",
    "https://www.w3.org/ns/activitystreams#Public"
  ],
  "id": "http://pasture-one-actor/activity/Yb2FRRKZzbc",
  "published": "2025-10-23T11:07:24Z",
  "object": {
    "type": "Note",
    "attributedTo": "http://pasture-one-actor/actor",
    "to": [
      "https://www.w3.org/ns/activitystreams#Public",
      "http://mastodon/users/hippo"
    ],
    "id": "http://pasture-one-actor/object/KcS3Dg3qUsk",
    "published": "2025-10-23T11:07:24Z",
    "content": "invalid uri",
    "inReplyTo": "http://invalid.example/"
  }
}

no result

Example 3

activity

{
  "@context": [
    "https://www.w3.org/ns/activitystreams",
    {
      "Hashtag": "as:Hashtag",
      "sensitive": "as:sensitive"
    }
  ],
  "type": "Create",
  "actor": "http://pasture-one-actor/actor",
  "to": [
    "http://mastodon/users/hippo",
    "https://www.w3.org/ns/activitystreams#Public"
  ],
  "id": "http://pasture-one-actor/activity/nAcbUv2H8mI",
  "published": "2025-10-23T11:07:38Z",
  "object": {
    "type": "Note",
    "attributedTo": "http://pasture-one-actor/actor",
    "to": [
      "https://www.w3.org/ns/activitystreams#Public",
      "http://mastodon/users/hippo"
    ],
    "id": "http://pasture-one-actor/object/LEpXy24jwfM",
    "published": "2025-10-23T11:07:38Z",
    "content": "list",
    "inReplyTo": [
      "http://pasture-one-actor/assets/note1.jsonap"
    ]
  }
}

no result

Example 4

activity

{
  "@context": [
    "https://www.w3.org/ns/activitystreams",
    {
      "Hashtag": "as:Hashtag",
      "sensitive": "as:sensitive"
    }
  ],
  "type": "Create",
  "actor": "http://pasture-one-actor/actor",
  "to": [
    "http://mastodon/users/hippo",
    "https://www.w3.org/ns/activitystreams#Public"
  ],
  "id": "http://pasture-one-actor/activity/QbVpnRHlu2w",
  "published": "2025-10-23T11:07:53Z",
  "object": {
    "type": "Note",
    "attributedTo": "http://pasture-one-actor/actor",
    "to": [
      "https://www.w3.org/ns/activitystreams#Public",
      "http://mastodon/users/hippo"
    ],
    "id": "http://pasture-one-actor/object/OO72CX2V_fw",
    "published": "2025-10-23T11:07:53Z",
    "content": "Link in inReplyTo",
    "inReplyTo": {
      "type": "Link",
      "href": "http://pasture-one-actor/assets/note1.jsonap"
    }
  }
}

no result

Example 5

activity

{
  "@context": [
    "https://www.w3.org/ns/activitystreams",
    {
      "Hashtag": "as:Hashtag",
      "sensitive": "as:sensitive"
    }
  ],
  "type": "Create",
  "actor": "http://pasture-one-actor/actor",
  "to": [
    "http://mastodon/users/hippo",
    "https://www.w3.org/ns/activitystreams#Public"
  ],
  "id": "http://pasture-one-actor/activity/MhDgeEjUjj0",
  "published": "2025-10-23T11:08:08Z",
  "object": {
    "type": "Note",
    "attributedTo": "http://pasture-one-actor/actor",
    "to": [
      "https://www.w3.org/ns/activitystreams#Public",
      "http://mastodon/users/hippo"
    ],
    "id": "http://pasture-one-actor/object/4lj2B9AwMHg",
    "published": "2025-10-23T11:08:08Z",
    "content": "two elements in inReplyTo",
    "inReplyTo": [
      "http://pasture-one-actor/assets/note1.jsonap",
      "http://pasture-one-actor/assets/note2.jsonap"
    ]
  }
}

no result

Example 6

activity

{
  "@context": [
    "https://www.w3.org/ns/activitystreams",
    {
      "Hashtag": "as:Hashtag",
      "sensitive": "as:sensitive"
    }
  ],
  "type": "Create",
  "actor": "http://pasture-one-actor/actor",
  "to": [
    "http://mastodon/users/hippo",
    "https://www.w3.org/ns/activitystreams#Public"
  ],
  "id": "http://pasture-one-actor/activity/IxRvyHVp4m4",
  "published": "2025-10-23T11:08:23Z",
  "object": {
    "type": "Note",
    "attributedTo": "http://pasture-one-actor/actor",
    "to": [
      "https://www.w3.org/ns/activitystreams#Public",
      "http://mastodon/users/hippo"
    ],
    "id": "http://pasture-one-actor/object/EHFvigF9j2k",
    "published": "2025-10-23T11:08:23Z",
    "content": "collection",
    "inReplyTo": {
      "type": "Collection",
      "items": [
        "http://pasture-one-actor/actor"
      ]
    }
  }
}

no result

Example 7

activity

{
  "@context": [
    "https://www.w3.org/ns/activitystreams",
    {
      "Hashtag": "as:Hashtag",
      "sensitive": "as:sensitive"
    }
  ],
  "type": "Create",
  "actor": "http://pasture-one-actor/actor",
  "to": [
    "http://mastodon/users/hippo",
    "https://www.w3.org/ns/activitystreams#Public"
  ],
  "id": "http://pasture-one-actor/activity/h3ZjaT3PdWY",
  "published": "2025-10-23T11:08:37Z",
  "object": {
    "type": "Note",
    "attributedTo": "http://pasture-one-actor/actor",
    "to": [
      "https://www.w3.org/ns/activitystreams#Public",
      "http://mastodon/users/hippo"
    ],
    "id": "http://pasture-one-actor/object/q_s_bmm33mc",
    "published": "2025-10-23T11:08:37Z",
    "content": "embedded note",
    "inReplyTo": {
      "@context": "https://www.w3.org/ns/activitystreams",
      "type": "Note",
      "id": "http://pasture-one-actor/assets/note1.jsonap",
      "to": [
        "as:Public"
      ],
      "attributedTo": "http://pasture-one-actor/actor",
      "content": "One",
      "published": "2024-01-06T13:11:45Z"
    }
  }
}

mastodon

{
  "id": "115423164363440228",
  "created_at": "2025-10-23T11:08:37.000Z",
  "in_reply_to_id": "111709172895877931",
  "in_reply_to_account_id": "115423154430999947",
  "sensitive": false,
  "spoiler_text": "",
  "visibility": "public",
  "language": null,
  "uri": "http://pasture-one-actor/object/q_s_bmm33mc",
  "url": "http://pasture-one-actor/object/q_s_bmm33mc",
  "replies_count": 0,
  "reblogs_count": 0,
  "favourites_count": 0,
  "edited_at": null,
  "favourited": false,
  "reblogged": false,
  "muted": false,
  "bookmarked": false,
  "content": "embedded note",
  "filtered": [],
  "reblog": null,
  "account": {
    "id": "115423154430999947",
    "username": "actor",
    "acct": "actor@pasture-one-actor",
    "display_name": "Test Actor",
    "locked": false,
    "bot": false,
    "discoverable": false,
    "indexable": false,
    "group": false,
    "created_at": "2025-10-23T00:00:00.000Z",
    "note": "",
    "url": "http://pasture-one-actor/actor",
    "uri": "http://pasture-one-actor/actor",
    "avatar": "http://mastodon/avatars/original/missing.png",
    "avatar_static": "http://mastodon/avatars/original/missing.png",
    "header": "http://mastodon/headers/original/missing.png",
    "header_static": "http://mastodon/headers/original/missing.png",
    "followers_count": 0,
    "following_count": 0,
    "statuses_count": 64,
    "last_status_at": "2025-10-23",
    "hide_collections": true,
    "emojis": [],
    "fields": []
  },
  "media_attachments": [],
  "mentions": [],
  "tags": [],
  "emojis": [],
  "quote": null,
  "card": null,
  "poll": null
}