diff --git a/README.md b/README.md
index 5992c27..bcc5faf 100644
--- a/README.md
+++ b/README.md
@@ -65,6 +65,8 @@ Expose a single `EventEmitter` API the UI drives over IPC (`apps/pearcord/index.
 
 **v0.8.506 (Phase 543):** Soundboard spans extend — `soundboard.stage` span; `activeChannelId` on play/upload/delete/stage ends; upload panel guild-loading guard; **soundboard-errors** includes stage. Bundle: `npm run test:phase543-soundboard`. See [SOUNDBOARD.md](../../docs/SOUNDBOARD.md).
 
+**v0.8.544 (Phase 581):** Reaction spans extend — `guildCount` on `reaction.toggle`/`reaction.gossip`/`reaction.list`/`reaction.clear`. UI `#expression-hub-panel-live` + unified **expression-errors** filter; clipboard `expressionHubPanelLiveBusy`/`channelExpressionEmojiCount`/`channelExpressionStickerCount`. Bundle: `npm run test:phase581-expression`. See [REACTIONS.md](../../docs/REACTIONS.md).
+
 **v0.8.543 (Phase 580):** Sticker spans extend — `guildCount` on `sticker.create`/`sticker.delete`/`sticker.stage`/`sticker.send`. UI `#sticker-hub-panel-live` + `syncStickerHubLivePanelDuringGuildLoading`; **sticker-errors** excludes audit/compliance/slash/webhook/bot/automation/emoji bleed; clipboard `stickerHubPanelLiveBusy`/`channelStickerCount`. Bundle: `npm run test:phase580-stickers`. See [STICKERS.md](../../docs/STICKERS.md).
 
 **v0.8.505 (Phase 542):** Sticker spans extend — `sticker.create`/`sticker.delete`/`sticker.stage`/`sticker.send` with `spanKind` + `activeChannelId`. UI split sticker compositor panels, `lastStickerTileName`, dedicated **sticker-errors** dev-log filter. Bundle: `npm run test:phase542-stickers`. See [STICKERS.md](../../docs/STICKERS.md).
diff --git a/index.js b/index.js
index 53de7a9..08898f3 100644
--- a/index.js
+++ b/index.js
@@ -13003,7 +13003,8 @@ class PearcordPlatform extends EventEmitter {
           guildId,
           channelId,
           emoji: emojiKey,
-          activeChannelId: this.activeChannelId
+          activeChannelId: this.activeChannelId,
+          guildCount: (this.guilds || []).length
         })
         gossipSent = true
       }
@@ -13028,7 +13029,8 @@ class PearcordPlatform extends EventEmitter {
         gossipSent,
         reactionCount,
         messageReactionCount,
-        activeChannelId: this.activeChannelId
+        activeChannelId: this.activeChannelId,
+        guildCount: (this.guilds || []).length
       })
       return result
     } catch (err) {
@@ -13338,7 +13340,8 @@ class PearcordPlatform extends EventEmitter {
           guildId: reactionGuildId,
           rowCount: rows.length,
           messageCount: Object.keys(reactions).length,
-          activeChannelId: this.activeChannelId
+          activeChannelId: this.activeChannelId,
+          guildCount: (this.guilds || []).length
         })
       } catch (err) {
         this.log.error('reaction.list error', {