fix: rag_server add/remove_directory crashes on a non-string directory arg (#1614)

tests/test_rag_server_directory_nonstring.py

@@ -0,0 +1,28 @@
+"""Regression: rag_server add/remove_directory must not crash on a non-string path.
+
+`directory = arguments.get("directory", "").strip()` runs before the surrounding
+try, so a non-string `directory` in the tool args (e.g. a number) raised
+AttributeError out of call_tool. Coerce non-strings to "".
+"""
+import asyncio
+
+import pytest
+
+pytest.importorskip("mcp")
+
+import mcp_servers.rag_server as rs
+
+
+def _call(monkeypatch, action, directory):
+    monkeypatch.setattr(rs, "_ensure_init", lambda: None)
+    return asyncio.run(rs.call_tool("manage_rag", {"action": action, "directory": directory}))
+
+
+def test_add_directory_non_string_does_not_crash(monkeypatch):
+    out = _call(monkeypatch, "add_directory", 123)
+    assert "needs a directory path" in out[0].text
+
+
+def test_remove_directory_non_string_does_not_crash(monkeypatch):
+    out = _call(monkeypatch, "remove_directory", ["x"])
+    assert "needs a directory path" in out[0].text