diff --git a/scripts/api.py b/scripts/api.py
index 4647471..c19f94b 100644
--- a/scripts/api.py
+++ b/scripts/api.py
@@ -537,7 +537,8 @@ def _execute_save_document(tool_input):
     except subprocess.TimeoutExpired:
         return "save_document: pandoc timed out (>120s)."
     except FileNotFoundError:
-        return "save_document: pandoc not installed."
+        return ("save_document: pandoc binary not reachable from the api process "
+                "(check that PATH in aaronai.service includes /usr/bin).")
     if proc.returncode != 0:
         err = proc.stderr.decode("utf-8", errors="replace")[:400]
         return f"save_document: pandoc failed: {err}"