Hashtags and JSON-LD

The examples here are various variations of creating the Hashtag element in the tag list. These variations can be useful in understanding how strict an application sees JSON-LD.

Hashtags are a good illustration of JSON-LD parsing as Hashtag is not part of the ActivityStreams vocabulary.

All examples except the first are questionable, and probably should not be used when publishing to the Fediverse. The examples marked with ⚠️ are expected to fail with a JSON-LD parser. The examples using as:Hashtag are expected to fail with a JSON only parser.

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": [
    "https://www.w3.org/ns/activitystreams#Public",
    "http://pleroma/users/full"
  ],
  "id": "http://pasture-one-actor/activity/IftLzu-OIvE",
  "published": "2025-09-01T08:19:44Z",
  "object": {
    "type": "Note",
    "attributedTo": "http://pasture-one-actor/actor",
    "to": [
      "https://www.w3.org/ns/activitystreams#Public",
      "http://pleroma/users/full"
    ],
    "id": "http://pasture-one-actor/object/Edk7QXBN2ik",
    "published": "2025-09-01T08:19:44Z",
    "content": "text",
    "tag": {
      "type": "Hashtag",
      "name": "#test"
    }
  }
}

pleroma

{
  "account": {
    "acct": "actor@pasture-one-actor",
    "avatar": "http://pleroma/images/avi.png",
    "avatar_static": "http://pleroma/images/avi.png",
    "bot": false,
    "created_at": "2025-09-01T08:18:11.000Z",
    "display_name": "Test Actor",
    "emojis": [],
    "fields": [],
    "followers_count": 0,
    "following_count": 0,
    "fqn": "actor@pasture-one-actor",
    "header": "http://pleroma/images/banner.png",
    "header_static": "http://pleroma/images/banner.png",
    "id": "AxkxK4Z31sK9DEpHO4",
    "last_status_at": "2025-09-01",
    "locked": false,
    "note": "",
    "pleroma": {
      "accepts_chat_messages": null,
      "also_known_as": [],
      "ap_id": "http://pasture-one-actor/actor",
      "avatar_description": "",
      "background_image": null,
      "favicon": null,
      "header_description": "",
      "hide_favorites": true,
      "hide_followers": false,
      "hide_followers_count": false,
      "hide_follows": false,
      "hide_follows_count": false,
      "is_admin": false,
      "is_confirmed": true,
      "is_moderator": false,
      "is_suggested": false,
      "privileges": [],
      "relationship": {},
      "skip_thread_containment": false,
      "tags": []
    },
    "source": {
      "fields": [],
      "note": "",
      "pleroma": {
        "actor_type": "Person",
        "discoverable": false
      },
      "sensitive": false
    },
    "statuses_count": 6,
    "url": "http://pasture-one-actor/actor",
    "username": "actor"
  },
  "application": null,
  "bookmarked": false,
  "card": null,
  "content": "text",
  "created_at": "2025-09-01T08:19:44.000Z",
  "edited_at": null,
  "emojis": [],
  "favourited": false,
  "favourites_count": 0,
  "id": "AxkxSfd36lDwTznV7g",
  "in_reply_to_account_id": null,
  "in_reply_to_id": null,
  "language": null,
  "media_attachments": [],
  "mentions": [
    {
      "acct": "full",
      "id": "AxkxCTwE4ZAKfmcWeW",
      "url": "http://pleroma/users/full",
      "username": "full"
    }
  ],
  "muted": false,
  "pinned": false,
  "pleroma": {
    "bookmark_folder": null,
    "content": {
      "text/plain": "text"
    },
    "context": "http://pasture-one-actor/object/Edk7QXBN2ik",
    "conversation_id": 1731579473,
    "direct_conversation_id": null,
    "emoji_reactions": [],
    "expires_at": null,
    "in_reply_to_account_acct": null,
    "list_id": null,
    "local": false,
    "parent_visible": false,
    "pinned_at": null,
    "quote": null,
    "quote_id": null,
    "quote_url": null,
    "quote_visible": false,
    "quotes_count": 0,
    "spoiler_text": {
      "text/plain": ""
    },
    "thread_muted": false
  },
  "poll": null,
  "reblog": null,
  "reblogged": false,
  "reblogs_count": 0,
  "replies_count": 0,
  "sensitive": false,
  "spoiler_text": "",
  "tags": [
    {
      "name": "test",
      "url": "http://pleroma/tag/test"
    }
  ],
  "text": null,
  "uri": "http://pasture-one-actor/object/Edk7QXBN2ik",
  "url": "http://pasture-one-actor/object/Edk7QXBN2ik",
  "visibility": "public"
}

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": [
    "https://www.w3.org/ns/activitystreams#Public",
    "http://pleroma/users/full"
  ],
  "id": "http://pasture-one-actor/activity/9RikzN43SRk",
  "published": "2025-09-01T08:19:45Z",
  "object": {
    "type": "Note",
    "attributedTo": "http://pasture-one-actor/actor",
    "to": [
      "https://www.w3.org/ns/activitystreams#Public",
      "http://pleroma/users/full"
    ],
    "id": "http://pasture-one-actor/object/P1h-2wpcWJM",
    "published": "2025-09-01T08:19:45Z",
    "content": "using as:Hashtag",
    "tag": {
      "type": "as:Hashtag",
      "name": "#test"
    }
  }
}

pleroma

{
  "account": {
    "acct": "actor@pasture-one-actor",
    "avatar": "http://pleroma/images/avi.png",
    "avatar_static": "http://pleroma/images/avi.png",
    "bot": false,
    "created_at": "2025-09-01T08:18:11.000Z",
    "display_name": "Test Actor",
    "emojis": [],
    "fields": [],
    "followers_count": 0,
    "following_count": 0,
    "fqn": "actor@pasture-one-actor",
    "header": "http://pleroma/images/banner.png",
    "header_static": "http://pleroma/images/banner.png",
    "id": "AxkxK4Z31sK9DEpHO4",
    "last_status_at": "2025-09-01",
    "locked": false,
    "note": "",
    "pleroma": {
      "accepts_chat_messages": null,
      "also_known_as": [],
      "ap_id": "http://pasture-one-actor/actor",
      "avatar_description": "",
      "background_image": null,
      "favicon": null,
      "header_description": "",
      "hide_favorites": true,
      "hide_followers": false,
      "hide_followers_count": false,
      "hide_follows": false,
      "hide_follows_count": false,
      "is_admin": false,
      "is_confirmed": true,
      "is_moderator": false,
      "is_suggested": false,
      "privileges": [],
      "relationship": {},
      "skip_thread_containment": false,
      "tags": []
    },
    "source": {
      "fields": [],
      "note": "",
      "pleroma": {
        "actor_type": "Person",
        "discoverable": false
      },
      "sensitive": false
    },
    "statuses_count": 7,
    "url": "http://pasture-one-actor/actor",
    "username": "actor"
  },
  "application": null,
  "bookmarked": false,
  "card": null,
  "content": "using as:Hashtag",
  "created_at": "2025-09-01T08:19:45.000Z",
  "edited_at": null,
  "emojis": [],
  "favourited": false,
  "favourites_count": 0,
  "id": "AxkxSjgO2IGp3VODse",
  "in_reply_to_account_id": null,
  "in_reply_to_id": null,
  "language": null,
  "media_attachments": [],
  "mentions": [
    {
      "acct": "full",
      "id": "AxkxCTwE4ZAKfmcWeW",
      "url": "http://pleroma/users/full",
      "username": "full"
    }
  ],
  "muted": false,
  "pinned": false,
  "pleroma": {
    "bookmark_folder": null,
    "content": {
      "text/plain": "using as:Hashtag"
    },
    "context": "http://pasture-one-actor/object/P1h-2wpcWJM",
    "conversation_id": 1425701947,
    "direct_conversation_id": null,
    "emoji_reactions": [],
    "expires_at": null,
    "in_reply_to_account_acct": null,
    "list_id": null,
    "local": false,
    "parent_visible": false,
    "pinned_at": null,
    "quote": null,
    "quote_id": null,
    "quote_url": null,
    "quote_visible": false,
    "quotes_count": 0,
    "spoiler_text": {
      "text/plain": ""
    },
    "thread_muted": false
  },
  "poll": null,
  "reblog": null,
  "reblogged": false,
  "reblogs_count": 0,
  "replies_count": 0,
  "sensitive": false,
  "spoiler_text": "",
  "tags": [],
  "text": null,
  "uri": "http://pasture-one-actor/object/P1h-2wpcWJM",
  "url": "http://pasture-one-actor/object/P1h-2wpcWJM",
  "visibility": "public"
}

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": [
    "https://www.w3.org/ns/activitystreams#Public",
    "http://pleroma/users/full"
  ],
  "id": "http://pasture-one-actor/activity/97aDFyRhaAo",
  "published": "2025-09-01T08:19:46Z",
  "object": {
    "type": "Note",
    "attributedTo": "http://pasture-one-actor/actor",
    "to": [
      "https://www.w3.org/ns/activitystreams#Public",
      "http://pleroma/users/full"
    ],
    "id": "http://pasture-one-actor/object/83GalSnbra4",
    "published": "2025-09-01T08:19:46Z",
    "content": "no type \u26a0\ufe0f ",
    "tag": {
      "name": "#test"
    }
  }
}

no result

Example 4

activity

{
  "@context": "https://www.w3.org/ns/activitystreams",
  "type": "Create",
  "actor": "http://pasture-one-actor/actor",
  "to": [
    "https://www.w3.org/ns/activitystreams#Public",
    "http://pleroma/users/full"
  ],
  "id": "http://pasture-one-actor/activity/k4HpQLC1mZo",
  "published": "2025-09-01T08:19:57Z",
  "object": {
    "type": "Note",
    "attributedTo": "http://pasture-one-actor/actor",
    "to": [
      "https://www.w3.org/ns/activitystreams#Public",
      "http://pleroma/users/full"
    ],
    "id": "http://pasture-one-actor/object/hPLTrTKcyRs",
    "published": "2025-09-01T08:19:57Z",
    "@context": "https://www.w3.org/ns/activitystreams",
    "content": "Hashtag not in @context \u26a0\ufe0f ",
    "tag": {
      "type": "Hashtag",
      "name": "#test"
    }
  }
}

pleroma

{
  "account": {
    "acct": "actor@pasture-one-actor",
    "avatar": "http://pleroma/images/avi.png",
    "avatar_static": "http://pleroma/images/avi.png",
    "bot": false,
    "created_at": "2025-09-01T08:18:11.000Z",
    "display_name": "Test Actor",
    "emojis": [],
    "fields": [],
    "followers_count": 0,
    "following_count": 0,
    "fqn": "actor@pasture-one-actor",
    "header": "http://pleroma/images/banner.png",
    "header_static": "http://pleroma/images/banner.png",
    "id": "AxkxK4Z31sK9DEpHO4",
    "last_status_at": "2025-09-01",
    "locked": false,
    "note": "",
    "pleroma": {
      "accepts_chat_messages": null,
      "also_known_as": [],
      "ap_id": "http://pasture-one-actor/actor",
      "avatar_description": "",
      "background_image": null,
      "favicon": null,
      "header_description": "",
      "hide_favorites": true,
      "hide_followers": false,
      "hide_followers_count": false,
      "hide_follows": false,
      "hide_follows_count": false,
      "is_admin": false,
      "is_confirmed": true,
      "is_moderator": false,
      "is_suggested": false,
      "privileges": [],
      "relationship": {},
      "skip_thread_containment": false,
      "tags": []
    },
    "source": {
      "fields": [],
      "note": "",
      "pleroma": {
        "actor_type": "Person",
        "discoverable": false
      },
      "sensitive": false
    },
    "statuses_count": 8,
    "url": "http://pasture-one-actor/actor",
    "username": "actor"
  },
  "application": null,
  "bookmarked": false,
  "card": null,
  "content": "Hashtag not in @context \u26a0\ufe0f ",
  "created_at": "2025-09-01T08:19:57.000Z",
  "edited_at": null,
  "emojis": [],
  "favourited": false,
  "favourites_count": 0,
  "id": "AxkxTqJOsFsjuCAL8C",
  "in_reply_to_account_id": null,
  "in_reply_to_id": null,
  "language": null,
  "media_attachments": [],
  "mentions": [
    {
      "acct": "full",
      "id": "AxkxCTwE4ZAKfmcWeW",
      "url": "http://pleroma/users/full",
      "username": "full"
    }
  ],
  "muted": false,
  "pinned": false,
  "pleroma": {
    "bookmark_folder": null,
    "content": {
      "text/plain": "Hashtag not in @context \u26a0\ufe0f "
    },
    "context": "http://pasture-one-actor/object/hPLTrTKcyRs",
    "conversation_id": 1981777238,
    "direct_conversation_id": null,
    "emoji_reactions": [],
    "expires_at": null,
    "in_reply_to_account_acct": null,
    "list_id": null,
    "local": false,
    "parent_visible": false,
    "pinned_at": null,
    "quote": null,
    "quote_id": null,
    "quote_url": null,
    "quote_visible": false,
    "quotes_count": 0,
    "spoiler_text": {
      "text/plain": ""
    },
    "thread_muted": false
  },
  "poll": null,
  "reblog": null,
  "reblogged": false,
  "reblogs_count": 0,
  "replies_count": 0,
  "sensitive": false,
  "spoiler_text": "",
  "tags": [
    {
      "name": "test",
      "url": "http://pleroma/tag/test"
    }
  ],
  "text": null,
  "uri": "http://pasture-one-actor/object/hPLTrTKcyRs",
  "url": "http://pasture-one-actor/object/hPLTrTKcyRs",
  "visibility": "public"
}

Example 5

activity

{
  "@context": "https://www.w3.org/ns/activitystreams",
  "type": "Create",
  "actor": "http://pasture-one-actor/actor",
  "to": [
    "https://www.w3.org/ns/activitystreams#Public",
    "http://pleroma/users/full"
  ],
  "id": "http://pasture-one-actor/activity/xAHAmEQXWVY",
  "published": "2025-09-01T08:19:57Z",
  "object": {
    "type": "Note",
    "attributedTo": "http://pasture-one-actor/actor",
    "to": [
      "https://www.w3.org/ns/activitystreams#Public",
      "http://pleroma/users/full"
    ],
    "id": "http://pasture-one-actor/object/QZXmk9zi8x8",
    "published": "2025-09-01T08:19:57Z",
    "@context": "https://www.w3.org/ns/activitystreams",
    "content": "Hashtag not in @context; as:Hashtag",
    "tag": {
      "type": "as:Hashtag",
      "name": "#test"
    }
  }
}

pleroma

{
  "account": {
    "acct": "actor@pasture-one-actor",
    "avatar": "http://pleroma/images/avi.png",
    "avatar_static": "http://pleroma/images/avi.png",
    "bot": false,
    "created_at": "2025-09-01T08:18:11.000Z",
    "display_name": "Test Actor",
    "emojis": [],
    "fields": [],
    "followers_count": 0,
    "following_count": 0,
    "fqn": "actor@pasture-one-actor",
    "header": "http://pleroma/images/banner.png",
    "header_static": "http://pleroma/images/banner.png",
    "id": "AxkxK4Z31sK9DEpHO4",
    "last_status_at": "2025-09-01",
    "locked": false,
    "note": "",
    "pleroma": {
      "accepts_chat_messages": null,
      "also_known_as": [],
      "ap_id": "http://pasture-one-actor/actor",
      "avatar_description": "",
      "background_image": null,
      "favicon": null,
      "header_description": "",
      "hide_favorites": true,
      "hide_followers": false,
      "hide_followers_count": false,
      "hide_follows": false,
      "hide_follows_count": false,
      "is_admin": false,
      "is_confirmed": true,
      "is_moderator": false,
      "is_suggested": false,
      "privileges": [],
      "relationship": {},
      "skip_thread_containment": false,
      "tags": []
    },
    "source": {
      "fields": [],
      "note": "",
      "pleroma": {
        "actor_type": "Person",
        "discoverable": false
      },
      "sensitive": false
    },
    "statuses_count": 9,
    "url": "http://pasture-one-actor/actor",
    "username": "actor"
  },
  "application": null,
  "bookmarked": false,
  "card": null,
  "content": "Hashtag not in @context; as:Hashtag",
  "created_at": "2025-09-01T08:19:57.000Z",
  "edited_at": null,
  "emojis": [],
  "favourited": false,
  "favourites_count": 0,
  "id": "AxkxTtzhBSUrKEyeyO",
  "in_reply_to_account_id": null,
  "in_reply_to_id": null,
  "language": null,
  "media_attachments": [],
  "mentions": [
    {
      "acct": "full",
      "id": "AxkxCTwE4ZAKfmcWeW",
      "url": "http://pleroma/users/full",
      "username": "full"
    }
  ],
  "muted": false,
  "pinned": false,
  "pleroma": {
    "bookmark_folder": null,
    "content": {
      "text/plain": "Hashtag not in @context; as:Hashtag"
    },
    "context": "http://pasture-one-actor/object/QZXmk9zi8x8",
    "conversation_id": 324615201,
    "direct_conversation_id": null,
    "emoji_reactions": [],
    "expires_at": null,
    "in_reply_to_account_acct": null,
    "list_id": null,
    "local": false,
    "parent_visible": false,
    "pinned_at": null,
    "quote": null,
    "quote_id": null,
    "quote_url": null,
    "quote_visible": false,
    "quotes_count": 0,
    "spoiler_text": {
      "text/plain": ""
    },
    "thread_muted": false
  },
  "poll": null,
  "reblog": null,
  "reblogged": false,
  "reblogs_count": 0,
  "replies_count": 0,
  "sensitive": false,
  "spoiler_text": "",
  "tags": [],
  "text": null,
  "uri": "http://pasture-one-actor/object/QZXmk9zi8x8",
  "url": "http://pasture-one-actor/object/QZXmk9zi8x8",
  "visibility": "public"
}