test: add comprehensive unit, integration, and e2e test suites

Introduce complete test coverage for the ARTEMIS platform across multiple layers:
Unit tests: Add tests for agent nodes (Planner, Operator, Validator, Diagnoser, FlashRunner, Explorer), tools, utils (OCR/XML fusion, UI hierarchy), and data engine.
Integration tests: Add live tool verification, reactive runner, IME, and standalone workflow tests.
E2E tests: Add end-to-end scenario tests for media playback and failure recovery flows.
Fixtures & mocks: Add mock inputs (audio, video, screenshot) and test utilities.

tests/unit/tools/test_read_logs_tool.py

@@ -0,0 +1,140 @@
+# Copyright 2026 Google LLC
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+from unittest.mock import MagicMock, patch
+
+from artemis.context import ArtemisContext
+from artemis.tools.base import ArtemisTool, ToolRegistry
+from artemis.tools.mobile.read_logs import (
+    ReadLogs,
+    ReadLogsArgs,
+    ReadLogsTool,
+    ReadLogsToolAlias,
+    get_read_logs_tool,
+    read_logs,
+)
+import pytest
+
+
+@pytest.fixture
+def mock_ctx():
+    ctx = MagicMock(spec=ArtemisContext)
+    return ctx
+
+
+def test_read_logs_tool_subclass_and_registry():
+    """Verify ReadLogsTool is a subclass of ArtemisTool and properly registered."""
+    assert issubclass(ReadLogsTool, ArtemisTool)
+    assert issubclass(ReadLogs, ArtemisTool)
+    assert issubclass(ReadLogsToolAlias, ArtemisTool)
+    assert isinstance(read_logs, ArtemisTool)
+    assert isinstance(read_logs, ReadLogsTool)
+
+    assert read_logs.name == "read_logs"
+    assert read_logs.category == "diagnostic"
+    assert read_logs.args_schema == ReadLogsArgs
+
+    # Registry lookup
+    reg_tool = ToolRegistry.get("read_logs")
+    assert reg_tool is not None
+    assert isinstance(reg_tool, ReadLogsTool)
+
+    # GenAI FunctionDeclaration export
+    declaration = read_logs.to_genai_declaration()
+    assert declaration.name == "read_logs"
+    assert "lines" in declaration.parameters.properties
+    assert "since_time" in declaration.parameters.properties
+    assert "until_time" in declaration.parameters.properties
+
+
+@pytest.mark.asyncio
+async def test_read_logs_direct_execution(mock_ctx):
+    """Verify direct execution of ReadLogsTool."""
+    mock_log_output = "08-12 10:00:00.000 1000 1000 I Test: Hello Logs\n"
+    with patch(
+        "artemis.tools.mobile.read_logs.fetch_and_filter_logs",
+        return_value=mock_log_output,
+    ) as mock_fetch:
+        result = await read_logs.execute(
+            ctx=mock_ctx,
+            lines=100,
+            since_time="08-12 09:59:00",
+            until_time="08-12 10:01:00",
+        )
+        mock_fetch.assert_called_once_with(
+            ctx=mock_ctx,
+            lines=100,
+            since_time="08-12 09:59:00",
+            until_time="08-12 10:01:00",
+        )
+        assert result == mock_log_output
+
+
+@pytest.mark.asyncio
+async def test_read_logs_default_lines(mock_ctx):
+    """Verify read_logs defaults lines to 200 when None."""
+    with patch(
+        "artemis.tools.mobile.read_logs.fetch_and_filter_logs",
+        return_value="logs",
+    ) as mock_fetch:
+        result = await read_logs.execute(ctx=mock_ctx, lines=None)
+        mock_fetch.assert_called_once_with(
+            ctx=mock_ctx,
+            lines=200,
+            since_time=None,
+            until_time=None,
+        )
+        assert result == "logs"
+
+
+@pytest.mark.asyncio
+async def test_read_logs_exception_handling(mock_ctx):
+    """Verify error handling when fetching logs raises an exception."""
+    with patch(
+        "artemis.tools.mobile.read_logs.fetch_and_filter_logs",
+        side_effect=RuntimeError("Device disconnected"),
+    ):
+        result = await read_logs.execute(ctx=mock_ctx)
+        assert "Failed to read logs: Device disconnected" in result
+
+
+@pytest.mark.asyncio
+async def test_read_logs_callable_execution(mock_ctx):
+    """Verify invoking read_logs directly as a callable."""
+    with patch(
+        "artemis.tools.mobile.read_logs.fetch_and_filter_logs",
+        return_value="sample log stream",
+    ):
+        result = await read_logs(ctx=mock_ctx, lines=50)
+        assert result == "sample log stream"
+
+
+@pytest.mark.asyncio
+async def test_get_read_logs_tool_langchain_ainvoke(mock_ctx):
+    """Verify get_read_logs_tool exports a LangChain tool that works with ainvoke."""
+    tool = get_read_logs_tool(mock_ctx)
+    assert tool.name == "read_logs"
+
+    with patch(
+        "artemis.tools.mobile.read_logs.fetch_and_filter_logs",
+        return_value="langchain log content",
+    ) as mock_fetch:
+        result = await tool.ainvoke({"lines": 300})
+        mock_fetch.assert_called_once_with(
+            ctx=mock_ctx,
+            lines=300,
+            since_time=None,
+            until_time=None,
+        )
+        assert result == "langchain log content"