@debugmcp/mcp-debugger/docs/archive/MCP_DEBUGGER_NON_DOCKER_TEST_REPORT.md

Run-time step-through debugging for LLM agents.

# MCP Debugger Server (Non-Docker) - Smoke Test Report

**Date**: June 17, 2025
**Tester**: Cline
**Test Environment**: Windows 11, Python 3.13.1 (explicitly provided)
**Server Name**: `mcp-debugger`

## 1. Executive Summary

This report details the smoke test results for the `mcp-debugger` server (non-Docker version) after multiple attempts to resolve Python discovery and script path issues. While initial problems with Python executable detection and relative script paths were successfully bypassed by providing explicit absolute paths, a critical issue with the `step_out` debugging operation persists, consistently resulting in a timeout.

## 2. Test Objectives

*   Verify the functionality of core debugging tools for the non-Docker `mcp-debugger` server.
*   Confirm resolution of Python executable discovery issues.
*   Confirm resolution of relative script path issues.
*   Identify and document any remaining critical issues.

## 3. Test Results

| Tool | Status | Notes |
| :--- | :--- | :--- |
| `create_debug_session` | ✅ Pass | Session created successfully. |
| `set_breakpoint` | ✅ Pass | Breakpoint set successfully at `examples/python/fibonacci.py:32`. |
| `start_debugging` | ✅ Pass | Debugger started and paused at breakpoint using absolute path `C:\Users\user\path\to\project\examples\python\fibonacci.py`. |
| `get_stack_trace` | ✅ Pass | Retrieved accurate call stack information. |
| `get_scopes` | ✅ Pass | Retrieved correct variable scopes. |
| `get_variables` | ✅ Pass | Inspected local variables successfully. |
| `continue_execution` | ✅ Pass | Resumed execution. |
| `step_over` | ✅ Pass | Correctly stepped over code statements. |
| `step_into` | ✅ Pass | Correctly stepped into function calls. |
| `step_out` | ❌ Fail | **Consistently timed out (5s)**. The debug adapter or program appears stuck during this operation. |
| `close_debug_session` | ✅ Pass | Session terminated cleanly after `step_out` failure. |

## 4. Key Findings and Recurring Issues

*   **Python Discovery Resolved (Workaround):** The server initially failed to find Python. This was bypassed by explicitly providing `pythonPath: "C:\\Python313\\python.exe"` during `create_debug_session`. The server's automatic Python discovery mechanism still appears to be problematic.
*   **Absolute Script Path Required:** The `start_debugging` command requires an absolute path for the script (e.g., `C:\\Users\\user\\path\\to\\project\\examples\\python\\fibonacci.py`). Relative paths do not work.
*   **Persistent `step_out` Timeout:** The most critical recurring issue is the `step_out` operation timing out. This indicates a fundamental problem with how the `mcp-debugger` server (non-Docker) handles stepping out of functions, potentially related to the debug adapter's state management or communication. This issue was observed across multiple test attempts.

## 5. Conclusion and Recommendation

The `mcp-debugger` server (non-Docker version) has improved in its ability to start debugging sessions when provided with explicit Python and absolute script paths. However, the persistent `step_out` timeout is a significant blocker for effective debugging.

**Recommendation:** Further investigation is required into the `step_out` implementation within the `mcp-debugger` server to diagnose and resolve the timeout issue. This may involve examining the interaction with the underlying debug adapter (debugpy) and ensuring proper state transitions during step operations.