diff --git a/tests/test_matrix_channel.py b/tests/test_matrix_channel.py
new file mode 100644
index 0000000..bc39097
--- /dev/null
+++ b/tests/test_matrix_channel.py
@@ -0,0 +1,113 @@
+from types import SimpleNamespace
+
+import pytest
+
+from nanobot.bus.queue import MessageBus
+from nanobot.channels.matrix import MatrixChannel
+from nanobot.config.schema import MatrixConfig
+
+
+class _DummyTask:
+    def __init__(self) -> None:
+        self.cancelled = False
+
+    def cancel(self) -> None:
+        self.cancelled = True
+
+
+class _FakeAsyncClient:
+    def __init__(self, homeserver, user, store_path, config) -> None:
+        self.homeserver = homeserver
+        self.user = user
+        self.store_path = store_path
+        self.config = config
+        self.user_id: str | None = None
+        self.access_token: str | None = None
+        self.device_id: str | None = None
+        self.load_store_called = False
+        self.join_calls: list[str] = []
+        self.callbacks: list[tuple[object, object]] = []
+
+    def add_event_callback(self, callback, event_type) -> None:
+        self.callbacks.append((callback, event_type))
+
+    def load_store(self) -> None:
+        self.load_store_called = True
+
+    async def join(self, room_id: str) -> None:
+        self.join_calls.append(room_id)
+
+    async def close(self) -> None:
+        return None
+
+
+def _make_config(**kwargs) -> MatrixConfig:
+    return MatrixConfig(
+        enabled=True,
+        homeserver="https://matrix.org",
+        access_token="token",
+        user_id="@bot:matrix.org",
+        **kwargs,
+    )
+
+
+@pytest.mark.asyncio
+async def test_start_skips_load_store_when_device_id_missing(
+    monkeypatch, tmp_path
+) -> None:
+    clients: list[_FakeAsyncClient] = []
+
+    def _fake_client(*args, **kwargs) -> _FakeAsyncClient:
+        client = _FakeAsyncClient(*args, **kwargs)
+        clients.append(client)
+        return client
+
+    def _fake_create_task(coro):
+        coro.close()
+        return _DummyTask()
+
+    monkeypatch.setattr("nanobot.channels.matrix.get_data_dir", lambda: tmp_path)
+    monkeypatch.setattr(
+        "nanobot.channels.matrix.AsyncClientConfig",
+        lambda **kwargs: SimpleNamespace(**kwargs),
+    )
+    monkeypatch.setattr("nanobot.channels.matrix.AsyncClient", _fake_client)
+    monkeypatch.setattr(
+        "nanobot.channels.matrix.asyncio.create_task", _fake_create_task
+    )
+
+    channel = MatrixChannel(_make_config(device_id=""), MessageBus())
+    await channel.start()
+
+    assert len(clients) == 1
+    assert clients[0].load_store_called is False
+
+    await channel.stop()
+
+
+@pytest.mark.asyncio
+async def test_room_invite_joins_when_allow_list_is_empty() -> None:
+    channel = MatrixChannel(_make_config(allow_from=[]), MessageBus())
+    client = _FakeAsyncClient("", "", "", None)
+    channel.client = client
+
+    room = SimpleNamespace(room_id="!room:matrix.org")
+    event = SimpleNamespace(sender="@alice:matrix.org")
+
+    await channel._on_room_invite(room, event)
+
+    assert client.join_calls == ["!room:matrix.org"]
+
+
+@pytest.mark.asyncio
+async def test_room_invite_respects_allow_list_when_configured() -> None:
+    channel = MatrixChannel(_make_config(allow_from=["@bob:matrix.org"]), MessageBus())
+    client = _FakeAsyncClient("", "", "", None)
+    channel.client = client
+
+    room = SimpleNamespace(room_id="!room:matrix.org")
+    event = SimpleNamespace(sender="@alice:matrix.org")
+
+    await channel._on_room_invite(room, event)
+
+    assert client.join_calls == []