diff --git a/bcc.py b/bcc.py
index 6d91287..dbd6110 100644
--- a/bcc.py
+++ b/bcc.py
@@ -57,6 +57,10 @@ from PySide6.QtWidgets import (
 
 import bcc_core as core
 
+# A full ~/.claude.json with history can be huge; parsing happens on the UI
+# thread during drag-and-drop import, so skip anything larger than this.
+MAX_DROP_IMPORT_BYTES = 5 * 1024 * 1024  # 5 MB
+
 # --- One-line rebrand: change this to recolor the whole app --------------- #
 ACCENT = "#f97316"  # warm orange
 ACCENT_DIM = "#c2570b"
@@ -2402,29 +2406,44 @@ class MainWindow(QMainWindow):
             e.acceptProposedAction()
 
     def dropEvent(self, e):
+        total_added, total_replaced, files_imported = 0, 0, 0
+        undo_pushed = False
         for u in e.mimeData().urls():
             path = u.toLocalFile()
             if not path.endswith(".json"):
                 continue
-            text = Path(path).read_text(encoding="utf-8")
+            p = Path(path)
+            if p.stat().st_size > MAX_DROP_IMPORT_BYTES:
+                QMessageBox.warning(
+                    self,
+                    "File too large",
+                    f"{p.name}:\nFile exceeds the 5 MB import limit and was skipped.",
+                )
+                continue
+            text = p.read_text(encoding="utf-8")
             try:
                 servers = core.parse_pasted_json(text)
             except Exception as ex:
-                QMessageBox.warning(self, "Couldn't import", f"{Path(path).name}:\n{ex}")
+                QMessageBox.warning(self, "Couldn't import", f"{p.name}:\n{ex}")
                 continue
-            self._push_undo()
+            if not undo_pushed:
+                self._push_undo()
+                undo_pushed = True
             added, replaced = 0, 0
             for name, data in servers.items():
                 a, r = self._import_server(name, data)
                 added += int(a)
                 replaced += int(r)
+            total_added += added
+            total_replaced += replaced
+            files_imported += 1
+        if files_imported:
             self._refresh_tables(select_index=len(self.servers) - 1)
             self._mark_dirty()
             self.status.setText(
-                f"Imported {added} added, {replaced} replaced from {Path(path).name}. "
-                "Review and Save."
+                f"Imported {total_added} added, {total_replaced} replaced from "
+                f"{files_imported} file(s). Review and Save."
             )
-            break
 
     def closeEvent(self, e):
         if self.dirty and not self._confirm_discard():