debug

Debug Session

The MCP debugger tools are ALREADY AVAILABLE. Do NOT search for .mcp.json or config files. Just call the tools directly.

I'll help you debug $ARGUMENTS.file using the MCP debugger.

Instructions

1. Detect Language: First, determine the programming language from the file extension:

   • .py → Python (uses debugpy)
   • .js, .ts, .mjs, .tsx → JavaScript/TypeScript (uses vscode-js-debug)
   • .go → Go (uses Delve)
   • .rs → Rust (uses CodeLLDB)

2. Create Session: Use create_debug_session with the detected language

3. Set Breakpoints: If a line number was provided, use set_breakpoint to add an initial breakpoint. Otherwise, suggest strategic breakpoints based on the code.

4. Start Debugging: Use start_debugging with the script path

5. When Stopped: When the program pauses at a breakpoint:

   • Use get_source_context to show the code around current location
   • Use get_variables to display local variables
   • Use get_stack_trace to show the call stack
   • Explain what the code is doing at this point

6. Interactive Debugging:

   • Ask if the user wants to step (in/over/out), continue, or inspect something
   • Use evaluate_expression to test hypotheses about variable values
   • Use expand_variable to drill into complex objects

7. Cleanup: When done, use terminate_session to clean up

Tips

• Set breakpoints before where you expect the issue to occur
• Compare expected vs actual variable values
• Watch for null/undefined values or unexpected types
• Check loop counters and array indices