diff --git a/packages/web/src/components/CopyableId.tsx b/packages/web/src/components/CopyableId.tsx
new file mode 100644
index 00000000..a19b95de
--- /dev/null
+++ b/packages/web/src/components/CopyableId.tsx
@@ -0,0 +1,43 @@
+import { useState } from 'react';
+import { Copy, Check } from 'lucide-react';
+import { shortId, copyText } from '../lib/clipboard';
+
+interface CopyableIdProps {
+  id: string;
+  /** Characters of the id to show before truncating (default 8). */
+  length?: number;
+  label?: string;
+  testId?: string;
+}
+
+/**
+ * Click-to-copy id chip (#23): shows a short id + copy icon; clicking copies the
+ * FULL id and flashes a transient "Copied!" confirmation. Reusable anywhere an
+ * id is shown (inspector, modals, lists).
+ */
+export function CopyableId({ id, length = 8, label = 'ID', testId = 'copyable-id' }: CopyableIdProps) {
+  const [copied, setCopied] = useState(false);
+  if (!id) return null;
+  const onCopy = async () => {
+    const ok = await copyText(id);
+    if (ok) {
+      setCopied(true);
+      setTimeout(() => setCopied(false), 1400);
+    }
+  };
+  return (
+    <button
+      type="button"
+      data-testid={testId}
+      onClick={onCopy}
+      title={`Copy ${label}: ${id}`}
+      aria-label={`Copy ${label}`}
+      className="group inline-flex items-center gap-1.5 font-mono text-[11px] text-gray-400 hover:text-gray-200 rounded px-1.5 py-0.5 hover:bg-gray-700/50 transition-colors"
+    >
+      <span>{shortId(id, length)}</span>
+      {copied
+        ? <span className="inline-flex items-center gap-1 text-emerald-400"><Check className="h-3 w-3" /> Copied!</span>
+        : <Copy className="h-3 w-3 opacity-60 group-hover:opacity-100" />}
+    </button>
+  );
+}
diff --git a/packages/web/src/components/NodeInspector.tsx b/packages/web/src/components/NodeInspector.tsx
index 3b3e7fcd..62dab7e2 100644
--- a/packages/web/src/components/NodeInspector.tsx
+++ b/packages/web/src/components/NodeInspector.tsx
@@ -4,6 +4,7 @@ import { useGraph } from '../contexts/GraphContext';
 import { getTypeConfig, getStatusConfig } from '../constants/workItemConstants';
 import type { WorkItemType } from '../constants/workItemConstants';
 import { NodeSubgraphPreview } from './NodeSubgraphPreview';
+import { CopyableId } from './CopyableId';
 
 // Heavy (markdown + Prism) — lazy so it's out of the main bundle until a node's
 // contents are first opened.
@@ -50,6 +51,7 @@ export function NodeInspector({ node, onClose, compact = false, rootTestId = 'no
         <div className="flex-1 min-w-0">
           <div className="text-[10px] uppercase tracking-wide" style={{ color: typeCfg.hexColor }}>{typeCfg.label}</div>
           <div className="text-sm font-semibold text-white truncate" title={node.title}>{node.title}</div>
+          <div className="mt-0.5"><CopyableId id={node.id} /></div>
         </div>
         <button onClick={onClose} className="p-1 text-gray-400 hover:text-white rounded hover:bg-gray-700/50" title="Close">
           <X className="h-4 w-4" />
diff --git a/packages/web/src/lib/__tests__/clipboard.test.ts b/packages/web/src/lib/__tests__/clipboard.test.ts
new file mode 100644
index 00000000..78b37ebe
--- /dev/null
+++ b/packages/web/src/lib/__tests__/clipboard.test.ts
@@ -0,0 +1,36 @@
+import { describe, it, expect, vi, beforeEach } from 'vitest';
+import { shortId, copyText } from '../clipboard';
+
+describe('shortId', () => {
+  it('takes the first 8 chars by default', () => {
+    expect(shortId('5134fc28-7ac2-4e33-acbf-e13c2962b8f1')).toBe('5134fc28');
+  });
+  it('respects a custom length', () => {
+    expect(shortId('abcdefghij', 4)).toBe('abcd');
+  });
+  it('returns short ids unchanged and handles empty/nullish', () => {
+    expect(shortId('abc')).toBe('abc');
+    expect(shortId('')).toBe('');
+    expect(shortId(undefined as any)).toBe('');
+  });
+});
+
+describe('copyText', () => {
+  beforeEach(() => { vi.restoreAllMocks(); });
+
+  it('uses navigator.clipboard.writeText when available and resolves true', async () => {
+    const writeText = vi.fn().mockResolvedValue(undefined);
+    vi.stubGlobal('navigator', { clipboard: { writeText } });
+    const ok = await copyText('hello');
+    expect(writeText).toHaveBeenCalledWith('hello');
+    expect(ok).toBe(true);
+  });
+
+  it('returns false when no clipboard mechanism is available', async () => {
+    vi.stubGlobal('navigator', {});
+    const doc: any = { queryCommandSupported: () => false };
+    vi.stubGlobal('document', doc);
+    const ok = await copyText('x');
+    expect(ok).toBe(false);
+  });
+});
diff --git a/packages/web/src/lib/clipboard.ts b/packages/web/src/lib/clipboard.ts
new file mode 100644
index 00000000..b27ece14
--- /dev/null
+++ b/packages/web/src/lib/clipboard.ts
@@ -0,0 +1,39 @@
+/**
+ * Clipboard helpers — copy text with a graceful fallback, and a short-id
+ * formatter for displaying long UUIDs compactly (click-to-copy, #23).
+ */
+
+/** First `len` chars of an id (UUIDs are unwieldy in the UI). Safe on empty/nullish. */
+export function shortId(id: string | null | undefined, len = 8): string {
+  if (!id) return '';
+  return id.length > len ? id.slice(0, len) : id;
+}
+
+/**
+ * Copy `text` to the clipboard. Prefers the async Clipboard API; falls back to
+ * a hidden textarea + execCommand for older/insecure contexts. Resolves true on
+ * success, false if no mechanism worked.
+ */
+export async function copyText(text: string): Promise<boolean> {
+  try {
+    if (typeof navigator !== 'undefined' && navigator.clipboard?.writeText) {
+      await navigator.clipboard.writeText(text);
+      return true;
+    }
+  } catch { /* fall through to legacy path */ }
+
+  try {
+    if (typeof document === 'undefined' || !document.body) return false;
+    const ta = document.createElement('textarea');
+    ta.value = text;
+    ta.style.position = 'fixed';
+    ta.style.opacity = '0';
+    document.body.appendChild(ta);
+    ta.select();
+    const ok = typeof document.execCommand === 'function' ? document.execCommand('copy') : false;
+    document.body.removeChild(ta);
+    return ok;
+  } catch {
+    return false;
+  }
+}
diff --git a/tests/e2e/copy-id.spec.ts b/tests/e2e/copy-id.spec.ts
new file mode 100644
index 00000000..e91a7266
--- /dev/null
+++ b/tests/e2e/copy-id.spec.ts
@@ -0,0 +1,30 @@
+import { test, expect } from '@playwright/test';
+import { login, TEST_USERS, getBaseURL } from '../helpers/auth';
+
+/**
+ * Click-to-copy node id (@copyid, #23): the node inspector shows a short id chip;
+ * clicking it copies the full id and flashes a transient "Copied!" confirmation.
+ */
+test.use({ permissions: ['clipboard-read', 'clipboard-write'] });
+
+test('node inspector id chip copies and confirms @copyid', async ({ page }) => {
+  test.setTimeout(90_000);
+  await page.addInitScript(() => localStorage.setItem('graphdone:viewMode', 'graph'));
+  await login(page, TEST_USERS.ADMIN);
+  await page.goto(`${getBaseURL()}/`, { waitUntil: 'domcontentloaded' });
+  await page.waitForSelector('.graph-container svg .node', { timeout: 15_000 });
+  await page.waitForTimeout(3500);
+
+  // Select a node → docked inspector opens.
+  await page.locator('.graph-container svg .node').first().click();
+  const chip = page.locator('[data-testid="copyable-id"]').first();
+  await expect(chip).toBeVisible({ timeout: 8000 });
+
+  await chip.click();
+  // Flashes "Copied!" on success.
+  await expect(chip.getByText('Copied!')).toBeVisible({ timeout: 4000 });
+
+  // And the clipboard actually holds a non-trivial id.
+  const clip = await page.evaluate(() => navigator.clipboard.readText().catch(() => ''));
+  expect(clip.length).toBeGreaterThan(8);
+});