diff --git a/changelog.mdx b/changelog.mdx
index c1db3554d..37dfe8dcf 100644
--- a/changelog.mdx
+++ b/changelog.mdx
@@ -7,6 +7,34 @@ keywords: ["changelog", "API updates", "release notes", "what's new", "API chang
 
 To subscribe to updates, please [**“Turn on notifications”**](https://help.x.com/en/managing-your-account/notifications-on-mobile-devices#:~:text=In%20the%20top%20menu,%20you,you%20would%20like%20to%20receive) for [**@API**](https://x.com/api). You can also follow this changelog in your feed reader via the [**RSS feed**](https://docs.x.com/changelog/rss.xml).
 
+<Update label="Aug 19, 2026" description="X API v2">
+  ### Broadcast chat history endpoint
+
+  Today, we added `GET /2/broadcasts/{id}/chat` for retrieving newest-first chat messages from a broadcast owned by the authenticated user. See the [Get broadcast chat history](/x-api/broadcasts/get-broadcast-chat-history) reference for parameters and response fields.
+
+  The endpoint supports `max_results` (1–200, default 100), `pagination_token`, `broadcast_chat_message.fields`, `user.fields`, and an `expansions=author_id` expansion that returns the message author in `includes.users`. It requires OAuth 2.0 with the `broadcast.read` scope.
+</Update>
+
+<Update label="Aug 19, 2026" description="X API v2">
+  ### New `block.write` OAuth 2.0 scope
+
+  We added a `block.write` OAuth 2.0 scope so apps can block and unblock accounts on a user's behalf. Request it during the authorization flow when your app needs to perform block or unblock actions.
+</Update>
+
+<Update label="Aug 19, 2026" description="X Ads API">
+  ### New `WEB_CONVERSION` metrics and `CONVERSION_TAGS` segmentation
+
+  We added eight new metrics to the `WEB_CONVERSION` metric group of the [X Ads API Analytics endpoints](/x-ads-api/analytics): `conversion_add_to_carts`, `conversion_checkouts_initiated`, `conversion_content_views`, `conversion_payment_info_additions`, `conversion_add_to_wishlists`, `conversion_searches`, `conversion_landing_page_views`, and `conversion_subscriptions`. Each returns the count of conversions of that type plus the corresponding sale amount and order quantity.
+
+  We also enabled a new `CONVERSION_TAGS` segmentation type. `CONVERSION_TAGS` is only compatible with the `WEB_CONVERSION` metric group.
+</Update>
+
+<Update label="Aug 13, 2026" description="X API">
+  ### Pay-per-use monthly Post read cap raised to 3 million
+
+  We raised the monthly Post read cap on pay-per-use plans from 2 million to 3 million reads per billing cycle. No action is required; the new cap applies automatically. See [Post cap](/x-api/fundamentals/post-cap) and [Pricing](/x-api/getting-started/pricing) for details.
+</Update>
+
 <Update label="Aug 13, 2026" description="X Ads API">
   ### Updated `video_total_views` definition