feat: add copy and truncation controls to tool call cards

src/renderer/components/WorkbenchControls.tsx

@@ -276,6 +276,50 @@ export function Composer({
   );
 }
 
+export const TOOL_TEXT_PREVIEW_LIMIT = 2000;
+
+function ToolTextSection({ title, text }: { title: string; text: string }) {
+  const [showAll, setShowAll] = useState(false);
+  const [copied, setCopied] = useState(false);
+  const isLong = text.length > TOOL_TEXT_PREVIEW_LIMIT;
+  const visible =
+    isLong && !showAll ? text.slice(0, TOOL_TEXT_PREVIEW_LIMIT) : text;
+  const copy = async () => {
+    try {
+      await navigator.clipboard.writeText(text);
+      setCopied(true);
+      window.setTimeout(() => setCopied(false), 1500);
+    } catch {
+      setCopied(false);
+    }
+  };
+  return (
+    <div className="wb-tool-section">
+      <div className="wb-tool-section-head">
+        <h3>{title}</h3>
+        <button
+          type="button"
+          className="wb-tool-copy"
+          aria-label={`Copy ${title.toLowerCase()}`}
+          onClick={() => void copy()}
+        >
+          {copied ? 'Copied' : 'Copy'}
+        </button>
+      </div>
+      <pre>{visible}</pre>
+      {isLong && (
+        <button
+          type="button"
+          className="wb-tool-toggle"
+          onClick={() => setShowAll((value) => !value)}
+        >
+          {showAll ? 'Show less' : 'Show more'}
+        </button>
+      )}
+    </div>
+  );
+}
+
 export const TranscriptRow = memo(function TranscriptRow({
   entry,
   expanded,
@@ -310,17 +354,14 @@ export const TranscriptRow = memo(function TranscriptRow({
             {entry.running ? 'Running' : entry.ok ? 'Done' : 'Failed'}
           </small>
         </summary>
-        <div className="wb-tool-section">
-          <h3>Input</h3>
-          <pre>{entry.input || 'No input.'}</pre>
-        </div>
-        <div className="wb-tool-section">
-          <h3>Output</h3>
-          <pre>
-            {entry.output ||
-              (entry.running ? 'Waiting for output…' : 'No output.')}
-          </pre>
-        </div>
+        <ToolTextSection title="Input" text={entry.input || 'No input.'} />
+        <ToolTextSection
+          title="Output"
+          text={
+            entry.output ||
+            (entry.running ? 'Waiting for output…' : 'No output.')
+          }
+        />
       </details>
     );
   return (

src/renderer/workbench.css

@@ -715,6 +715,26 @@ html[data-reduced-motion='true'] .wb-shell *::after {
   text-transform: uppercase;
   color: var(--muted);
 }
+.wb-tool-section-head {
+  display: flex;
+  align-items: center;
+  justify-content: space-between;
+  gap: 12px;
+  padding-right: 12px;
+}
+.wb-tool-copy,
+.wb-tool-toggle {
+  border: 1px solid var(--line-soft);
+  background: transparent;
+  color: var(--copy);
+  font-size: 11px;
+  line-height: 16px;
+  padding: 2px 8px;
+  cursor: pointer;
+}
+.wb-tool-toggle {
+  margin: 0 12px 12px;
+}
 .wb-tool-section + .wb-tool-section {
   border-top: 1px solid var(--line-soft);
 }

tests/integration/ToolCard.test.tsx

@@ -1,5 +1,5 @@
-import { describe, expect, it, beforeEach } from 'vitest';
-import { render, cleanup } from '@testing-library/react';
+import { describe, expect, it, beforeEach, vi } from 'vitest';
+import { render, cleanup, fireEvent } from '@testing-library/react';
 import { TranscriptRow } from '../../src/renderer/components/WorkbenchControls';
 import type { Entry } from '../../src/renderer/timeline';
 
@@ -33,6 +33,43 @@ describe('<TranscriptRow> tool card', () => {
     expect(container.textContent).toContain('Done');
   });
 
+  it('copies the exact output text and shows Copied', async () => {
+    const writeText = vi.fn().mockResolvedValue(undefined);
+    Object.defineProperty(navigator, 'clipboard', {
+      value: { writeText },
+      configurable: true,
+    });
+    const expanded = new Map<string, boolean>([[toolEntry.key, true]]);
+    const { getByRole } = render(
+      <TranscriptRow entry={toolEntry} expanded={expanded} />,
+    );
+    fireEvent.click(getByRole('button', { name: 'Copy output' }));
+    expect(writeText).toHaveBeenCalledWith('Edited /repo/src/app.ts');
+    await vi.waitFor(() =>
+      expect(getByRole('button', { name: 'Copy output' }).textContent).toBe(
+        'Copied',
+      ),
+    );
+  });
+
+  it('truncates long output and expands on Show more', () => {
+    const longOutput = `start-${'x'.repeat(2500)}-end-marker`;
+    const longEntry: Extract<Entry, { kind: 'tool' }> = {
+      ...toolEntry,
+      key: 'tool-3',
+      output: longOutput,
+    };
+    const expanded = new Map<string, boolean>([[longEntry.key, true]]);
+    const { container, getByRole } = render(
+      <TranscriptRow entry={longEntry} expanded={expanded} />,
+    );
+    expect(container.textContent).not.toContain('end-marker');
+    fireEvent.click(getByRole('button', { name: 'Show more' }));
+    expect(container.textContent).toContain('end-marker');
+    fireEvent.click(getByRole('button', { name: 'Show less' }));
+    expect(container.textContent).not.toContain('end-marker');
+  });
+
   it('shows running state and waiting output while a tool runs', () => {
     const running: Extract<Entry, { kind: 'tool' }> = {
       ...toolEntry,