Show disabled assistant copy button while streaming

Author: shivamhwp

apps/web/src/components/chat/MessageCopyButton.tsx

@@ -10,6 +10,7 @@ export const MessageCopyButton = memo(function MessageCopyButton({
   size = "xs",
   variant = "outline",
   className,
+  disabled = false,
   onCopy,
   onError,
 }: {
@@ -18,6 +19,7 @@ export const MessageCopyButton = memo(function MessageCopyButton({
   size?: "xs" | "icon-xs";
   variant?: "outline" | "ghost";
   className?: string;
+  disabled?: boolean;
   onCopy?: () => void;
   onError?: (error: Error) => void;
 }) {
@@ -33,6 +35,7 @@ export const MessageCopyButton = memo(function MessageCopyButton({
       size={size}
       variant={variant}
       className={cn(className)}
+      disabled={disabled}
       onClick={() => copyToClipboard(text, undefined)}
       title={buttonTitle}
       aria-label={buttonTitle}

apps/web/src/components/chat/MessagesTimeline.logic.test.ts

@@ -158,21 +158,37 @@ describe("resolveAssistantMessageCopyState", () => {
         streaming: false,
       }),
     ).toEqual({
+      disabled: false,
       text: "Ship it",
       visible: true,
     });
   });
 
-  it("hides copy while an assistant message is still streaming", () => {
+  it("keeps copy visible but disabled while an assistant message is still streaming", () => {
     expect(
       resolveAssistantMessageCopyState({
         showCopyButton: true,
         text: "Still streaming",
         streaming: true,
       }),
     ).toEqual({
+      disabled: true,
       text: "Still streaming",
-      visible: false,
+      visible: true,
+    });
+  });
+
+  it("keeps copy visible while a terminal assistant message is streaming before text arrives", () => {
+    expect(
+      resolveAssistantMessageCopyState({
+        showCopyButton: true,
+        text: "",
+        streaming: true,
+      }),
+    ).toEqual({
+      disabled: true,
+      text: null,
+      visible: true,
     });
   });
 
@@ -184,6 +200,7 @@ describe("resolveAssistantMessageCopyState", () => {
         streaming: false,
       }),
     ).toEqual({
+      disabled: false,
       text: null,
       visible: false,
     });
@@ -197,6 +214,7 @@ describe("resolveAssistantMessageCopyState", () => {
         streaming: false,
       }),
     ).toEqual({
+      disabled: false,
       text: "Interim thought",
       visible: false,
     });

apps/web/src/components/chat/MessagesTimeline.logic.ts

@@ -72,7 +72,8 @@ export function resolveAssistantMessageCopyState({
   const hasText = text !== null && text.trim().length > 0;
   return {
     text: hasText ? text : null,
-    visible: showCopyButton && hasText && !streaming,
+    visible: showCopyButton && (hasText || streaming),
+    disabled: streaming,
   };
 }
 

apps/web/src/components/chat/MessagesTimeline.test.tsx

@@ -108,4 +108,53 @@ describe("MessagesTimeline", () => {
     expect(markup).toContain("Context compacted");
     expect(markup).toContain("Work log");
   });
+
+  it("renders the assistant copy button in a disabled state while streaming", async () => {
+    const { MessagesTimeline } = await import("./MessagesTimeline");
+    const markup = renderToStaticMarkup(
+      <MessagesTimeline
+        hasMessages
+        isWorking={false}
+        activeTurnInProgress
+        activeTurnStartedAt="2026-03-17T19:12:28.000Z"
+        scrollContainer={null}
+        timelineEntries={[
+          {
+            id: "assistant-entry",
+            kind: "message",
+            createdAt: "2026-03-17T19:12:28.000Z",
+            message: {
+              id: MessageId.make("assistant-1"),
+              role: "assistant",
+              text: "",
+              turnId: "turn-1" as never,
+              createdAt: "2026-03-17T19:12:28.000Z",
+              streaming: true,
+            },
+          },
+        ]}
+        completionDividerBeforeEntryId={null}
+        completionSummary={null}
+        turnDiffSummaryByAssistantMessageId={new Map()}
+        nowIso="2026-03-17T19:12:30.000Z"
+        expandedWorkGroups={{}}
+        onToggleWorkGroup={() => {}}
+        changedFilesExpandedByTurnId={{}}
+        onSetChangedFilesExpanded={() => {}}
+        onOpenTurnDiff={() => {}}
+        revertTurnCountByUserMessageId={new Map()}
+        onRevertUserMessage={() => {}}
+        isRevertingCheckpoint={false}
+        onImageExpand={() => {}}
+        activeThreadEnvironmentId={ACTIVE_THREAD_ENVIRONMENT_ID}
+        markdownCwd={undefined}
+        resolvedTheme="light"
+        timestampFormat="locale"
+        workspaceRoot={undefined}
+      />,
+    );
+
+    expect(markup).toContain('aria-label="Copy assistant response"');
+    expect(markup).toContain("disabled");
+  }, 10_000);
 });

apps/web/src/components/chat/MessagesTimeline.tsx

@@ -537,6 +537,7 @@ export const MessagesTimeline = memo(function MessagesTimeline({
                         size="icon-xs"
                         variant="outline"
                         className="border-border/50 bg-background/35 text-muted-foreground/45 shadow-none hover:border-border/70 hover:bg-background/55 hover:text-muted-foreground/70"
+                        disabled={assistantCopyState.disabled}
                         onCopy={() => {
                           toastManager.add({
                             type: "success",