From 09bcf5a9370e8bc60e1d0a784c360b9721fc0256 Mon Sep 17 00:00:00 2001
From: Brooklyn Nicholson <brooklyn.bb.nicholson@gmail.com>
Date: Thu, 11 Jun 2026 22:27:39 -0500
Subject: [PATCH] fix(desktop): move tool-row copy control into expanded body
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

The per-row copy control lived in the header's trailing slot as a 24px
button that depended on a `group-hover/tool-row` group that exists nowhere
in the tree. It therefore stayed `opacity-0` yet remained clickable — an
invisible hit-target straddling the disclosure caret and duration, making
the caret hard to click without firing a copy.

Move copy into the expanded body's top-right (matching the code-block
convention) where it can't fight the caret for the right edge, and make it
actually visible (subtle at rest, full on hover/focus). The header right
edge now belongs solely to the duration label + caret.

Tradeoff: copy is only reachable once a row is expanded; rows with no
expandable body no longer surface a copy control.
---
 .../components/assistant-ui/tool-fallback.tsx | 20 ++++++++++++++++---
 1 file changed, 17 insertions(+), 3 deletions(-)

diff --git a/apps/desktop/src/components/assistant-ui/tool-fallback.tsx b/apps/desktop/src/components/assistant-ui/tool-fallback.tsx
index 391510f71bf..b5d65b5571e 100644
--- a/apps/desktop/src/components/assistant-ui/tool-fallback.tsx
+++ b/apps/desktop/src/components/assistant-ui/tool-fallback.tsx
@@ -279,11 +279,14 @@ function ToolEntry({ part }: ToolEntryProps) {
 
   const copyAction = useMemo(() => toolCopyPayload(part, view), [part, view])
 
+  // The header trailing slot only carries the live duration timer while the
+  // tool is running. The copy control used to live here too, but an
+  // `opacity-0` (yet still clickable) button straddling the caret/duration made
+  // the disclosure caret hard to hit. Copy now lives in the expanded body's
+  // top-right, where it can't fight the caret for the right edge.
   const trailing =
     isPending && !embedded ? (
       <ActivityTimerText className={TOOL_HEADER_DURATION_CLASS} seconds={elapsed} />
-    ) : !isPending && copyAction.text ? (
-      <CopyButton appearance="tool-row" label={copyAction.label} stopPropagation text={copyAction.text} />
     ) : undefined
 
   return (
@@ -322,7 +325,18 @@ function ToolEntry({ part }: ToolEntryProps) {
       </div>
       {isPending && <PendingToolApproval part={part} />}
       {open && (
-        <div className="grid w-full min-w-0 max-w-full gap-1.5 overflow-hidden p-1.5">
+        <div className="relative grid w-full min-w-0 max-w-full gap-1.5 overflow-hidden p-1.5">
+          {copyAction.text && (
+            <CopyButton
+              appearance="inline"
+              className="absolute right-1.5 top-1.5 z-10 h-5 gap-0 rounded-md border border-(--ui-stroke-tertiary) bg-background/80 px-1 opacity-60 backdrop-blur-sm transition-opacity hover:opacity-100 focus-visible:opacity-100"
+              iconClassName="size-3"
+              label={copyAction.label}
+              showLabel={false}
+              stopPropagation
+              text={copyAction.text}
+            />
+          )}
           {!embedded && view.previewTarget && isPreviewableTarget(view.previewTarget) && (
             <PreviewAttachment source="tool-result" target={view.previewTarget} />
           )}