Update app.py

app.py

@@ -917,4 +917,29 @@ def debug_db_head(n: int = 5):
         "rows": int(len(df)),
         "head": df.head(n).to_dict(orient="records"),
         "columns": list(df.columns),
+    }
+
+import pandas as pd  # make sure this is at the top of the file if not already
+# from here: after append_and_retrain
+
+@app.get("/debug/db_tail")
+def debug_db_tail(n: int = 10):
+    """
+    Returns the last n rows of fingerprints_db.csv so you can verify
+    that new points are really being appended inside the container.
+    """
+    if not os.path.exists(FINGERPRINT_CSV):
+        return {"ok": False, "error": f"{FINGERPRINT_CSV} not found"}
+
+    try:
+        df = pd.read_csv(FINGERPRINT_CSV)
+    except Exception as e:
+        return {"ok": False, "error": f"Failed to read CSV: {e}"}
+
+    tail = df.tail(n)
+    return {
+        "ok": True,
+        "rows": tail.to_dict(orient="records"),
+        "n_rows_total": int(df.shape[0]),
+        "n_returned": int(tail.shape[0]),
     }