diff --git a/tools/cross-ref-checker.mjs b/tools/cross-ref-checker.mjs
new file mode 100644
index 00000000..076e79e9
--- /dev/null
+++ b/tools/cross-ref-checker.mjs
@@ -0,0 +1,84 @@
+#!/usr/bin/env node
+import { readFileSync, existsSync } from 'fs';
+import { join } from 'path';
+
+const NORMATIVE_FILES = {
+  Pravila: 'docs/Pravila_raboty_Claude_v1_1.md',
+  CLAUDE: 'CLAUDE.md',
+  Tooling: 'docs/Tooling_v8_3.md',
+  PSR_v1: 'docs/Plugin_stack_rules_v1.md',
+  MEMORY: 'MEMORY.md',
+};
+
+const VERSION_RE = /v(\d+\.\d+(?:\.\d+)?)/;
+const CROSS_REF_RE = /\b(Pravila|CLAUDE|Tooling|PSR_v1|MEMORY|PSR|Plugin_stack_rules|Pravila_raboty_Claude)\s+v(\d+\.\d+(?:\.\d+)?)/g;
+const VERSIYA_RE = /\*\*Версия:\*\*\s*v?(\d+\.\d+(?:\.\d+)?)/;
+const CROSS_REF_SCAN_LINES = 50;
+
+export function extractVersion(text) {
+  const head = text.split('\n').slice(0, 30);
+  for (const line of head) {
+    const m = line.match(VERSIYA_RE);
+    if (m) return m[1];
+  }
+  for (const line of head.slice(0, 10)) {
+    const m = line.match(VERSION_RE);
+    if (m) return m[1];
+  }
+  return null;
+}
+
+export function extractCrossRefs(text, maxLines = CROSS_REF_SCAN_LINES) {
+  const top = text.split('\n').slice(0, maxLines).join('\n');
+  const refs = [];
+  for (const match of top.matchAll(CROSS_REF_RE)) {
+    let name = match[1];
+    if (name === 'PSR' || name === 'Plugin_stack_rules') name = 'PSR_v1';
+    if (name === 'Pravila_raboty_Claude') name = 'Pravila';
+    refs.push({ name, version: match[2] });
+  }
+  return refs;
+}
+
+export function detectMismatches(files) {
+  const headerVersions = {};
+  for (const [shortName, path] of Object.entries(NORMATIVE_FILES)) {
+    const entry = Object.entries(files).find(([k]) => k === path || k.endsWith(path));
+    if (entry) headerVersions[shortName] = extractVersion(entry[1]);
+  }
+  const mismatches = [];
+  for (const [path, text] of Object.entries(files)) {
+    const refs = extractCrossRefs(text);
+    for (const r of refs) {
+      const expected = headerVersions[r.name];
+      if (expected && expected !== r.version) {
+        mismatches.push({ from: path, to: r.name, expected, found: r.version });
+      }
+    }
+  }
+  return mismatches;
+}
+
+function loadFiles(root = process.cwd()) {
+  const out = {};
+  for (const [, path] of Object.entries(NORMATIVE_FILES)) {
+    const abs = join(root, path);
+    if (existsSync(abs)) out[path] = readFileSync(abs, 'utf-8');
+  }
+  return out;
+}
+
+if (process.argv[1] && process.argv[1].replace(/\\/g, '/').endsWith('/cross-ref-checker.mjs')) {
+  const files = loadFiles();
+  const m = detectMismatches(files);
+  if (m.length === 0) {
+    console.log(`[cross-ref-checker] OK — 0 drift in ${Object.keys(files).length} files`);
+    process.exit(0);
+  }
+  console.error(`[cross-ref-checker] FAIL — version drift detected:`);
+  for (const x of m) {
+    console.error(`  ${x.from} references ${x.to} v${x.found}, but ${x.to} header is v${x.expected}`);
+  }
+  console.error(`Update cross-refs in offending files.`);
+  process.exit(1);
+}
diff --git a/tools/cross-ref-checker.test.mjs b/tools/cross-ref-checker.test.mjs
new file mode 100644
index 00000000..82cbd587
--- /dev/null
+++ b/tools/cross-ref-checker.test.mjs
@@ -0,0 +1,45 @@
+import { describe, it, expect } from 'vitest';
+import { extractVersion, extractCrossRefs, detectMismatches } from './cross-ref-checker.mjs';
+
+describe('extractVersion', () => {
+  it('extracts version from header', () => {
+    const text = '# Pravila v1.30 от 18.05.2026';
+    expect(extractVersion(text)).toBe('1.30');
+  });
+
+  it('returns null if no version', () => {
+    expect(extractVersion('# Untitled')).toBeNull();
+  });
+});
+
+describe('extractCrossRefs', () => {
+  it('extracts cross-refs like "Pravila v1.29"', () => {
+    const text = 'See Pravila v1.29 and Tooling v2.15.';
+    const refs = extractCrossRefs(text);
+    expect(refs).toContainEqual({ name: 'Pravila', version: '1.29' });
+    expect(refs).toContainEqual({ name: 'Tooling', version: '2.15' });
+  });
+});
+
+describe('detectMismatches', () => {
+  it('detects when fileA references fileB v1.29 but fileB header is v1.30', () => {
+    const files = {
+      'A.md': '# A v1.0 — cross-refs: Pravila v1.29',
+      'docs/Pravila_raboty_Claude_v1_1.md': '# Pravila v1.30',
+    };
+    const m = detectMismatches(files);
+    expect(m).toHaveLength(1);
+    expect(m[0].from).toBe('A.md');
+    expect(m[0].to).toBe('Pravila');
+    expect(m[0].expected).toBe('1.30');
+    expect(m[0].found).toBe('1.29');
+  });
+
+  it('passes when in sync', () => {
+    const files = {
+      'A.md': '# A v1.0 — Pravila v1.30',
+      'docs/Pravila_raboty_Claude_v1_1.md': '# Pravila v1.30',
+    };
+    expect(detectMismatches(files)).toHaveLength(0);
+  });
+});