Draft changelog: weekly recap for Sep 17, 2026

changelog.mdx

@@ -7,6 +7,58 @@ keywords: ["changelog", "API updates", "release notes", "what's new", "API chang
 
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+<Update label="Sep 17, 2026" description="This week">
+  ### New
+
+  #### Livestream API (Enterprise)
+
+  The [Livestream API](/livestream-api/introduction) is now published. Enterprise customers can create and manage live video broadcasts on X end to end: persistent RTMP/RTMPS [stream sources](/livestream-api/sources/overview), the full [broadcast lifecycle](/livestream-api/broadcasts/overview) (create, publish, monitor, end), [scheduled broadcasts](/livestream-api/scheduled-broadcasts/overview) (one-time and recurring), reading live chat via the X Activity API, and [sending](/livestream-api/chat/send-chat-message) and [moderating](/livestream-api/chat/accessing-live-chat) chat messages.
+
+  Livestream endpoints are Enterprise-only. If you'd like access, fill out the [Enterprise interest form](/forms/enterprise-api-interest).
+
+  ### Updated
+
+  #### Ads MCP expands to 74 tools
+
+  [Ads MCP](/x-ads-api/mcp) is now in production with 74 tools (up from 23). MCP-capable clients such as Grok, Claude Code, or custom agents can now cover the full Ads workflow conversationally:
+
+  - **Conversion tracking** — create and manage web event tags (pixels) and set one as a line item's `primary_web_event_tag`, so Sales / website-conversion campaigns work end to end.
+  - **Audiences** — build custom audiences and do-not-reach lists, and estimate audience size before spending.
+  - **Creatives and media** — manage cards, the media library, account media, and media creatives.
+  - **App campaigns** — app event tags, tracking tags, and app lists.
+  - **Precise reads** — single-entity `get_*` tools for line items, cards, funding instruments, promoted posts, custom audiences, and more.
+
+  Media library writes require the optional `media.write` OAuth scope. See the [full tool list and setup recipes](/x-ads-api/mcp).
+
+  #### Broadcast chat moderators (Livestream API)
+
+  The Livestream API now documents dedicated moderator endpoints for live chat:
+
+  - [Add a moderator](/livestream-api/chat/add-moderator)
+  - [List moderators](/livestream-api/chat/list-moderators)
+  - [Remove a moderator](/livestream-api/chat/remove-moderator)
+
+  The [delete message](/livestream-api/chat/delete-chat-message), [mute user](/livestream-api/chat/mute-chat-user), and [unmute user](/livestream-api/chat/unmute-chat-user) endpoints can now be called by any assigned moderator, not just the broadcast owner.
+
+  #### `post_id` qualifier for `like.create` (X Activity API)
+
+  Subscriptions to [`like.create`](/x-api/activity/introduction#supported-event-types) now accept a `post_id` qualifier so you can receive events only for likes on a specific Post:
+
+  ```json
+  {
+    "event_type": "like.create",
+    "user_id": "1234567890",
+    "qualifiers": { "post_id": "1234567890123456789" }
+  }
+  ```
+
+  ### Fixed
+
+  #### `liking_user_id` in `like.create` payload sample
+
+  The [`like.create` event payload reference](/x-api/activity/event-payloads) now includes `liking_user_id` in the field table and JSON sample, and the sample `includes.users` array now contains the liking user alongside the liked Post's author. The payload itself is unchanged — the sample matches what the endpoint has always delivered.
+</Update>
+
 <Update label="Sep 16, 2026" description="X Ads API">
   ### REGIONS segmentation for Analytics