# Handoff Report — 2026-06-27T02:17:05+09:00

## 1. Observation
We ran the pytest coverage command on the five target modules:
`CommandLine: .venv/bin/pytest tests/unit/tools/analysis/test_capa_tools.py tests/unit/tools/analysis/test_lief_tools.py tests/unit/tools/malware/test_adaptive_vaccine.py tests/unit/tools/common/test_memory_tools.py tests/unit/tools/common/test_patch_explainer.py -v`

Direct coverage output:
```
reversecore_mcp/tools/analysis/capa_tools.py               66     43    35%   21, 56-164
reversecore_mcp/tools/analysis/lief_tools.py              196    125    36%   33-114, 135, 146-154, 161, 167, 174, 187, 191-193, 197-203, 209-214, 218-223, 253, 263, 273-276, 302-320, 324, 340-369
reversecore_mcp/tools/malware/adaptive_vaccine.py         400    230    42%   27-28, 133, 217, 236, 250-255, 262-310, 321-329, 350-357, 366-380, 386-436, 546-622, 639-775
reversecore_mcp/tools/common/memory_tools.py              115     56    51%   65-66, 197-210, 232-243, 276-297, 326-341, 373-383, 411-426, 453-467, 491-499
reversecore_mcp/tools/common/patch_explainer.py            88     37    58%   55, 59, 79-164, 207-208, 213, 219
```

Additionally, we inspected the test source code for `patch_explainer.py` (`tests/unit/tools/common/test_patch_explainer.py`) and observed the following:
```python
        mock_diff_result = MagicMock()
        mock_diff_result.status = "success"
        mock_diff_result.data = {
            "changed_functions": [{"name": "main", "code_a": "mov eax, 1", "code_b": "mov ebx, 2"}],
            "similarity": 0.5,
        }
```
However, `reversecore_mcp/tools/common/patch_explainer.py` implements the following lookup:
```python
69:     changes = diff_result.data.get("changes", [])
70:     if not changes:
71:         return success(
72:             {
73:                 "summary": "No significant code changes detected.",
74:                 "changes": [],
75:             }
76:         )
```

## 2. Logic Chain
1. **Target Identification**: Pytest coverage results identify specific uncovered lines for each target module.
2. **capa_tools.py**: The coverage is low (35%) because the native CAPA dependency is not installed in the test environment, causing `_is_capa_available()` to return `False` and preventing execution of `run_capa`.
3. **lief_tools.py**: The coverage is low (36%) because mitigations extraction and text formatting are not directly invoked in the tests. The process pool execution isolates `_run_lief_in_process` which prevents coverage collection for the subprocess worker.
4. **adaptive_vaccine.py**: The coverage is 42% because `_create_binary_patch` (including Capstone disassembly, backup writing, and rollback logic) is completely mocked out in the orchestrator test and never tested in isolation.
5. **memory_tools.py**: The coverage is 51% because 8 out of the 11 registered MCP tools are completely omitted from the unit tests.
6. **patch_explainer.py**: The coverage is 58% and misses the main analysis loop (lines 79-164) because of a mock-schema mismatch. The test mocks `diff_result.data` to contain a `changed_functions` key, whereas the code checks the `changes` key. This causes `changes` to evaluate to `[]` and triggers an early return.
7. **Resolution**: By mocking the external dependencies (CAPA, LIEF, Capstone, ProcessPoolExecutor) and correcting the mock-schema mismatch, all of these paths can be tested in isolation.

## 3. Caveats
- Since this is a read-only investigation, no code or test files were modified. The proposed fixes and mock implementations are conceptual, documented in `analysis.md`, and ready for implementation.
- This investigation assumes that the code is run on a Mac/zsh system where `.venv/bin/pytest` is accessible.

## 4. Conclusion
The baseline coverage of the target tools can be significantly improved. The most critical findings are:
1. **Mock schema mismatch in `patch_explainer.py`**: Fixing the mock schema from `changed_functions` to `changes` will instantly cover the entire decompile and explain loop.
2. **Missing tests in `memory_tools.py`**: Implementing simple unit tests for the 8 missing memory tools will raise coverage close to 100%.
3. **Mocking native libraries**: Writing mocks for Vivisect CAPA, LIEF binary objects, and Capstone disassembler constants will allow testing anti-analysis, patching, and binary translation flows safely.

## 5. Verification Method
1. Inspect the detailed report `/Users/sjkim1127/Reversecore_MCP/.agents/explorer_m1_1/analysis.md` to verify all proposed mocking strategies and code snippets.
2. Once the implementer implements the test strategies, verify using:
   `pytest --cov=reversecore_mcp --cov-report=term-missing`
   Confirm that the coverage metrics for the 5 target files exceed 90% and that the overall coverage threshold is satisfied.
