diff --git a/src/components/message-stream.tsx b/src/components/message-stream.tsx
index d0b867f9..e3d3649b 100644
--- a/src/components/message-stream.tsx
+++ b/src/components/message-stream.tsx
@@ -380,7 +380,9 @@ export default function MessageStream(props: MessageStreamProps) {
 
         const toolSignature = createToolSignature(message, toolPart, originalIndex, messageInfo)
         const contentKey = createToolContentKey(toolPart, messageInfo)
+        tokenSegments.push(`tool:${toolKey}:${partVersion}`)
         const toolEntry = toolItemCache.get(toolKey)
+
         if (toolEntry && toolEntry.signature === toolSignature) {
           if (toolEntry.contentKey !== contentKey) {
             const updatedItem: ToolDisplayItem = {
diff --git a/src/styles/components.css b/src/styles/components.css
index 434b5011..907ad8e0 100644
--- a/src/styles/components.css
+++ b/src/styles/components.css
@@ -696,7 +696,7 @@ button.button-primary:disabled {
   height: 2.75rem;
   border-radius: 9999px;
   border: 1px solid var(--border-base);
-  background-color: var(--surface-secondary);
+  background-color: transparent;
   color: var(--text-primary);
   box-shadow: 0 10px 25px rgba(0, 0, 0, 0.08);
   transition: background-color 0.2s ease, color 0.2s ease, transform 0.2s ease, box-shadow 0.2s ease;