diff --git a/plugins/voyage/playground/voyage-playground.html b/plugins/voyage/playground/voyage-playground.html
index 6be85c3..2baf445 100644
--- a/plugins/voyage/playground/voyage-playground.html
+++ b/plugins/voyage/playground/voyage-playground.html
@@ -28,6 +28,40 @@
     })();
   </script>
 
+  <script>
+// Voyage anchor parser — mirrored verbatim from lib-parsers anchor-parser.mjs.
+// Pure I/O-free parser for v4.2 voyage:anchor markdown comments.
+// Format reference: voyage anchor id ANN-NNNN target heading-slug line N snippet ≤80c intent fix change question block.
+// Constants mirror Node-side ANCHOR_LINE_RE + ATTR_RE + ID_RE (anchor-parser.mjs:20-25). Inline keeps file COLON COLON  scheme compat (no ES-module).
+    var VOYAGE_ANCHOR_RE = /^(\s*)<!--\s*voyage:anchor\s+([^>]+?)\s*-->\s*$/;
+    var VOYAGE_ANCHOR_ATTR_RE = /(\w+)="([^"]*)"/g;
+    var VOYAGE_ANCHOR_ID_RE = /^ANN-\d{4}$/;
+    var VOYAGE_ANCHOR_INTENTS = ['fix', 'change', 'question', 'block'];
+
+    function parseAnchor(line) {
+      if (typeof line !== 'string') return null;
+      var m = line.match(VOYAGE_ANCHOR_RE);
+      if (!m) return null;
+      var attrs = {};
+      VOYAGE_ANCHOR_ATTR_RE.lastIndex = 0;
+      var a;
+      while ((a = VOYAGE_ANCHOR_ATTR_RE.exec(m[2])) !== null) attrs[a[1]] = a[2];
+      if (!attrs.id || !VOYAGE_ANCHOR_ID_RE.test(attrs.id)) return null;
+      if (typeof attrs.target !== 'string' || attrs.target.length === 0) return null;
+      var lineNum = null;
+      if (attrs.line !== undefined) {
+        var n = parseInt(attrs.line, 10);
+        if (!Number.isInteger(n) || n <= 0) return null;
+        lineNum = n;
+      }
+      var snippet = attrs.snippet || null;
+      if (snippet !== null && snippet.length > 80) return null;
+      var intent = attrs.intent || null;
+      if (intent !== null && VOYAGE_ANCHOR_INTENTS.indexOf(intent) === -1) return null;
+      return { id: attrs.id, target: attrs.target, line: lineNum, snippet: snippet, intent: intent };
+    }
+  </script>
+
   <link rel="stylesheet" href="vendor/playground-design-system/fonts.css">
   <link rel="stylesheet" href="vendor/playground-design-system/tokens.css">
   <link rel="stylesheet" href="vendor/playground-design-system/base.css">
diff --git a/plugins/voyage/tests/playground/voyage-playground.test.mjs b/plugins/voyage/tests/playground/voyage-playground.test.mjs
index e724ab6..0d48e23 100644
--- a/plugins/voyage/tests/playground/voyage-playground.test.mjs
+++ b/plugins/voyage/tests/playground/voyage-playground.test.mjs
@@ -200,3 +200,23 @@ test('voyage-playground.html declares popstate handler (v4.3 Step 15 back/forwar
   const text = readFileSync(HTML, 'utf-8');
   assert.match(text, /'popstate'/, 'popstate listener required for browser back/forward');
 });
+
+test('voyage-playground.html declares VOYAGE_ANCHOR_RE constant (v4.3 Step 16 anchor allowlist)', () => {
+  const text = readFileSync(HTML, 'utf-8');
+  assert.match(text, /VOYAGE_ANCHOR_RE\s*=\s*\/\^/, 'VOYAGE_ANCHOR_RE regex constant required');
+  assert.match(text, /VOYAGE_ANCHOR_ATTR_RE\s*=\s*\//, 'VOYAGE_ANCHOR_ATTR_RE constant required');
+  assert.match(text, /VOYAGE_ANCHOR_ID_RE\s*=\s*\/\^ANN-/, 'VOYAGE_ANCHOR_ID_RE constant required');
+});
+
+test('voyage-playground.html anchor regex matches Node-side allowlist (v4.3 Step 16 cross-file sync)', () => {
+  const html = readFileSync(HTML, 'utf-8');
+  const node = readFileSync(join(ROOT, 'lib', 'parsers', 'anchor-parser.mjs'), 'utf-8');
+  const htmlMatch = html.match(/voyage:anchor[^/]+/)?.[0];
+  const nodeMatch = node.match(/voyage:anchor[^/]+/)?.[0];
+  assert.equal(htmlMatch, nodeMatch, 'first voyage:anchor token in HTML must mirror Node-side parser exactly');
+});
+
+test('voyage-playground.html declares parseAnchor validator (v4.3 Step 16)', () => {
+  const text = readFileSync(HTML, 'utf-8');
+  assert.match(text, /function\s+parseAnchor\s*\(\s*line\s*\)/, 'parseAnchor(line) function required');
+});