diff --git a/pageindex/page_index.py b/pageindex/page_index.py
index aed38cf..ff74770 100644
--- a/pageindex/page_index.py
+++ b/pageindex/page_index.py
@@ -47,6 +47,19 @@ def _secure_doc_text(text: str) -> str:
     """Sanitize + delimiter-frame a PDF text block before LLM injection."""
     return _wrap_doc_text(_sanitize_doc_text(text))
 
+_PHYSICAL_INDEX_MARKER_RE = re.compile(r"^<physical_index_(\d+)>$")
+
+def _parse_physical_index(raw):
+    if raw is None:
+        marker_match = _PHYSICAL_INDEX_MARKER_RE.match(str(raw).strip())
+        if marker_match:
+            return int(marker_match.group(1))
+        try:
+            return int(raw)
+        except (TypeError, ValueError)
+            return None
+
+
 def _validate_physical_indices(toc: list, total_pages: int, start_index: int = 1) -> list:
     """Nullify any physical_index the LLM produced that falls outside the real page range."""
     max_idx = start_index + total_pages - 1
@@ -54,13 +67,11 @@ def _validate_physical_indices(toc: list, total_pages: int, start_index: int = 1
         raw = entry.get("physical_index")
         if raw is None:
             continue
-        try:
-            val = int(raw)
-        except (TypeError, ValueError):
-            entry["physical_index"] = None
-            continue
-        if not (start_index <= val <= max_idx):
+        val = _parse_physical_index(raw)
+        if val is None or not (start_index <= val <= max_idx):
             entry["physical_index"] = None
+        else:
+            entry["physical_index"] = val
     return toc
     
 ################### check title in page #########################################################
@@ -216,8 +227,8 @@ def check_if_toc_transformation_is_complete(content, toc, model=None):
 
     prompt = (
         prompt
-        + '/n Raw Table of contents:\n' + _secure_doc_text(content)
-        + '/n Cleaned Table of contents:\n' + _secure_doc_text(str(toc))
+        + '\n Raw Table of contents:\n' + _secure_doc_text(content)
+        + '\n Cleaned Table of contents:\n' + _secure_doc_text(str(toc))
     )
     response = llm_completion(model=model, prompt=prompt)
     json_content = extract_json(response)