diff --git a/tools/version_manager.py b/tools/version_manager.py
new file mode 100644
index 0000000..1ac7247
--- /dev/null
+++ b/tools/version_manager.py
@@ -0,0 +1,88 @@
+"""
+Version Manager — archives and rolls back teacher skill versions.
+Adapted from colleague-skill's version_manager.py.
+"""
+
+import json
+import os
+import shutil
+from datetime import datetime
+
+MAX_VERSIONS = 10
+
+
+def list_versions(teacher_dir: str) -> list:
+    """List all archived versions of a teacher skill."""
+    versions_dir = os.path.join(teacher_dir, "versions")
+    if not os.path.exists(versions_dir):
+        return []
+
+    versions = []
+    for entry in sorted(os.listdir(versions_dir)):
+        entry_path = os.path.join(versions_dir, entry)
+        if os.path.isdir(entry_path) and entry.startswith("v"):
+            files = os.listdir(entry_path)
+            mtime = os.path.getmtime(entry_path)
+            versions.append({
+                "version": entry[1:],
+                "archived_at": datetime.fromtimestamp(mtime).strftime("%Y-%m-%d %H:%M"),
+                "files": files,
+            })
+    return versions
+
+
+def rollback(teacher_dir: str, target_version: str) -> bool:
+    """Roll back a teacher skill to a previous version. Backs up current state first."""
+    target_dir = os.path.join(teacher_dir, "versions", f"v{target_version}")
+    if not os.path.isdir(target_dir):
+        return False
+
+    meta_path = os.path.join(teacher_dir, "meta.json")
+    current_version = "unknown"
+    if os.path.exists(meta_path):
+        with open(meta_path, "r", encoding="utf-8") as f:
+            meta = json.load(f)
+        current_version = meta.get("version", "unknown")
+        backup_dir = os.path.join(teacher_dir, "versions", f"v{current_version}_before_rollback")
+        os.makedirs(backup_dir, exist_ok=True)
+        for fname in ["SKILL.md", "teaching.md", "voice.md", "meta.json"]:
+            src = os.path.join(teacher_dir, fname)
+            if os.path.exists(src):
+                shutil.copy2(src, backup_dir)
+
+    for fname in ["SKILL.md", "teaching.md", "voice.md", "meta.json"]:
+        src = os.path.join(target_dir, fname)
+        if os.path.exists(src):
+            shutil.copy2(src, os.path.join(teacher_dir, fname))
+
+    if os.path.exists(meta_path):
+        with open(meta_path, "r", encoding="utf-8") as f:
+            meta = json.load(f)
+        meta["rollback_from"] = current_version
+        meta["updated_at"] = datetime.now().strftime("%Y-%m-%d")
+        with open(meta_path, "w", encoding="utf-8") as f:
+            json.dump(meta, f, ensure_ascii=False, indent=2)
+
+    return True
+
+
+def cleanup_old_versions(teacher_dir: str) -> int:
+    """Remove old versions beyond MAX_VERSIONS limit."""
+    versions_dir = os.path.join(teacher_dir, "versions")
+    if not os.path.exists(versions_dir):
+        return 0
+
+    entries = []
+    for entry in os.listdir(versions_dir):
+        entry_path = os.path.join(versions_dir, entry)
+        if os.path.isdir(entry_path):
+            entries.append((entry_path, os.path.getmtime(entry_path)))
+
+    entries.sort(key=lambda x: x[1], reverse=True)
+
+    removed = 0
+    for path, _ in entries[MAX_VERSIONS:]:
+        shutil.rmtree(path)
+        removed += 1
+
+    return removed