diff --git a/apps/web/src/components/ChatView.tsx b/apps/web/src/components/ChatView.tsx
index 38cc2aed8666669a93583cf4382ee49c7b5042dc..2a0c6ccaf9b4ea3b8ce783b50e6c2d347793f765 100644
--- a/apps/web/src/components/ChatView.tsx
+++ b/apps/web/src/components/ChatView.tsx
@@ -361,12 +361,16 @@ const VscodeEntryIcon = memo(function VscodeEntryIcon(props: {
 const ComposerCommandMenuItem = memo(function ComposerCommandMenuItem(props: {
   item: ComposerCommandItem;
   resolvedTheme: "light" | "dark";
+  isActive: boolean;
   onSelect: (item: ComposerCommandItem) => void;
 }) {
   return (
     <CommandItem
       value={props.item.id}
-      className="cursor-pointer select-none gap-2"
+      className={cn(
+        "cursor-pointer select-none gap-2",
+        props.isActive && "bg-accent text-accent-foreground",
+      )}
       onMouseDown={(event) => {
         event.preventDefault();
       }}
@@ -400,6 +404,7 @@ const ComposerCommandMenu = memo(function ComposerCommandMenu(props: {
   resolvedTheme: "light" | "dark";
   isLoading: boolean;
   triggerKind: ComposerTriggerKind | null;
+  activeItemId: string | null;
   onHighlightedItemChange: (itemId: string | null) => void;
   onSelect: (item: ComposerCommandItem) => void;
 }) {
@@ -419,6 +424,7 @@ const ComposerCommandMenu = memo(function ComposerCommandMenu(props: {
               key={item.id}
               item={item}
               resolvedTheme={props.resolvedTheme}
+              isActive={props.activeItemId === item.id}
               onSelect={props.onSelect}
             />
           ))}
@@ -1389,6 +1395,26 @@ export default function ChatView({ threadId }: ChatViewProps) {
     scheduleStickToBottom();
   }, [phase, scheduleStickToBottom, timelineEntries]);
 
+  useEffect(() => {
+    setExpandedWorkGroups({});
+  }, [activeThread?.id]);
+
+  useEffect(() => {
+    if (!composerMenuOpen) {
+      setComposerHighlightedItemId(null);
+      return;
+    }
+    setComposerHighlightedItemId((existing) =>
+      existing && composerMenuItems.some((item) => item.id === existing)
+        ? existing
+        : (composerMenuItems[0]?.id ?? null),
+    );
+  }, [composerMenuItems, composerMenuOpen]);
+
+  useEffect(() => {
+    setIsRevertingCheckpoint(false);
+  }, [activeThread?.id]);
+
   useEffect(() => {
     if (!activeThread?.id || terminalState.terminalOpen) return;
     const frame = window.requestAnimationFrame(() => {
@@ -2274,12 +2300,14 @@ export default function ChatView({ threadId }: ChatViewProps) {
       workspaceEntriesQuery.isLoading ||
       workspaceEntriesQuery.isFetching);
 
-  const onPromptChange = useCallback((nextPrompt: string, nextCursor: number) => {
+  const onPromptChange = useCallback((nextPrompt: string, nextCursor: number, cursorAdjacentToMention: boolean) => {
     promptRef.current = nextPrompt;
     setPrompt(nextPrompt);
     setComposerCursor(nextCursor);
     setComposerTrigger(
-      detectComposerTrigger(nextPrompt, expandCollapsedComposerCursor(nextPrompt, nextCursor)),
+      cursorAdjacentToMention
+        ? null
+        : detectComposerTrigger(nextPrompt, expandCollapsedComposerCursor(nextPrompt, nextCursor)),
     );
   }, [setPrompt]);
 
@@ -2301,8 +2329,8 @@ export default function ChatView({ threadId }: ChatViewProps) {
         const selectedItem = activeComposerMenuItemRef.current ?? currentItems[0];
         if (selectedItem) {
           onSelectComposerItem(selectedItem);
+          return true;
         }
-        return true;
       }
     }
 
@@ -2464,6 +2492,7 @@ export default function ChatView({ threadId }: ChatViewProps) {
                     resolvedTheme={resolvedTheme}
                     isLoading={isComposerMenuLoading}
                     triggerKind={composerTriggerKind}
+                    activeItemId={activeComposerMenuItem?.id ?? null}
                     onHighlightedItemChange={onComposerMenuItemHighlighted}
                     onSelect={onSelectComposerItem}
                   />
diff --git a/apps/web/src/components/ComposerPromptEditor.tsx b/apps/web/src/components/ComposerPromptEditor.tsx
index 6601e558edfaabbd28483963b437baac90fa5621..30dbb9dceb1bf2d8200222748152b0aca338eafc 100644
--- a/apps/web/src/components/ComposerPromptEditor.tsx
+++ b/apps/web/src/components/ComposerPromptEditor.tsx
@@ -395,7 +395,7 @@ interface ComposerPromptEditorProps {
   disabled: boolean;
   placeholder: string;
   className?: string;
-  onChange: (nextValue: string, nextCursor: number) => void;
+  onChange: (nextValue: string, nextCursor: number, cursorAdjacentToMention: boolean) => void;
   onCommandKeyDown?: (
     key: "ArrowDown" | "ArrowUp" | "Enter" | "Tab",
     event: KeyboardEvent,
@@ -540,6 +540,29 @@ function ComposerMentionSelectionNormalizePlugin() {
   return null;
 }
 
+function $isCursorAdjacentToMention(): boolean {
+  const selection = $getSelection();
+  if (!$isRangeSelection(selection) || !selection.isCollapsed()) return false;
+  const anchorNode = selection.anchor.getNode();
+
+  if (anchorNode instanceof ComposerMentionNode) return true;
+
+  if ($isElementNode(anchorNode)) {
+    const childIndex = selection.anchor.offset - 1;
+    if (childIndex >= 0) {
+      const child = anchorNode.getChildAtIndex(childIndex);
+      if (child instanceof ComposerMentionNode) return true;
+    }
+  }
+
+  if ($isTextNode(anchorNode) && selection.anchor.offset === 0) {
+    const prev = anchorNode.getPreviousSibling();
+    if (prev instanceof ComposerMentionNode) return true;
+  }
+
+  return false;
+}
+
 function ComposerMentionBackspacePlugin() {
   const [editor] = useLexicalComposerContext();
 
@@ -662,7 +685,7 @@ function ComposerPromptEditorInner({
         value: snapshotRef.current.value,
         cursor: boundedCursor,
       };
-      onChangeRef.current(snapshotRef.current.value, boundedCursor);
+      onChangeRef.current(snapshotRef.current.value, boundedCursor, false);
     },
     [editor],
   );
@@ -715,7 +738,7 @@ function ComposerPromptEditorInner({
         value: nextValue,
         cursor: nextCursor,
       };
-      onChangeRef.current(nextValue, nextCursor);
+      onChangeRef.current(nextValue, nextCursor, $isCursorAdjacentToMention());
     });
   }, []);