debugger

=== SECTION 1: IDENTITY ===

name: debugger description: "Systematic debugging skill. 7-step workflow: Reproduce, Minimize, Hypothesize, Instrument, Fix, Prevent, Verify. Activate when troubleshooting errors." version: 3.0.0 phase: utility category: utility scope: project tags:

• debugging
• troubleshooting
• errors
• systematic

=== SECTION 2: CAPABILITIES ===

mcp_servers:

• context7 allowed_tools:
• notify_user
• view_file
• write_to_file
• run_command
• grep_search
• replace_file_content dependencies: [] context: required: [] optional:
  • path: project/docs/active/backend/ purpose: Implementation context
  • path: project/docs/active/frontend/ purpose: UI context reads:
• type: bug_report from: project/docs/active/bugs/
• type: error_logs from: project/ produces:
• type: debug_report
• type: fix
• type: regression_test

=== SECTION 3: WORKFLOW ===

presets:

• backend
• fullstack
• minimal receives_from:
• skill: qa-lead docs:
  • doc_type: bug-report trigger: bugs_found
• skill: backend-go-expert docs:
  • doc_type: error-report trigger: bugs_found
• skill: frontend-nuxt docs:
  • doc_type: error-report trigger: bugs_found

delegates_to:

• skill: qa-lead docs:
  • doc_type: debug-report trigger: implementation_complete

return_paths: []

=== SECTION 4: DOCUMENTS ===

creates:

• doc_type: debug-report path: project/docs/active/bugs/ doc_category: bugs lifecycle: per-feature initial_status: Draft trigger: implementation_complete updates:
• doc_type: known-issues path: project/docs/ lifecycle: living trigger: on_complete
• doc_type: artifact-registry path: project/docs/ lifecycle: living trigger: on_complete archives:
• doc_type: debug-report destination: project/docs/closed// trigger: qa_signoff

=== SECTION 5: VALIDATION ===

pre_handoff: protocols: - traceability - handoff checks: - artifact_registry_updated quality_gates: []

=== SECTION 6: REQUIRED_SECTIONS ===

required_sections: - frontmatter - when_to_activate - language_requirements - workflow - team_collaboration - when_to_delegate - brain_to_docs - document_lifecycle - handoff_protocol

Debugger

[!IMPORTANT]

First Step: Read Project Config & MCP

Before making technical decisions, always check:

File	Purpose
project/CONFIG.yaml	Stack versions, modules, architecture
mcp.yaml	Project MCP server config
mcp/	Project-specific MCP tools/resources

Use project MCP server (named after project, e.g. mcp_<project-name>_*):

• list_resources → see available project data
• *_tools → project-specific actions (db, cache, jobs, etc.)

Use mcp_context7 for library docs:

• Check mcp.yaml → context7.default_libraries for pre-configured libs
• Example: libraryId: /nuxt/nuxt, query: "Nuxt 4 composables"

When to Activate

• Runtime errors, crashes
• Failing tests
• "It used to work" regressions
• Unexpected behavior
• Performance/timeout issues (initial triage)

The 7-Step Debug Workflow

[!CAUTION] DO NOT SKIP STEPS! Each is critical for systematic debugging.

Step 1: Reproduce (Test Cases First) 🔁

MANDATORY: You must create a reproduction artifact.

• Unit Test: If logic error, write a failing unit test.
• Script: If integration error, write a standalone repro script.
• Config: If environment error, document exact config to repro.

Status Check: Do you have a "Red" test? If no, go back.

Step 2: Minimize 🎯

Reduce to smallest repro:

• One file
• One function
• Smallest dataset
• Remove unrelated code

Step 3: Hypothesize 🧠

Form 2-5 hypotheses, ranked by likelihood:

1. Most likely cause
2. Second candidate
3. Edge case possibility
4. (Optional) Unlikely but possible

Step 4: Instrument 🔧

Add temporary debugging:

• Logging statements
• Assertions
• Breakpoints
• Print variables at key points

Use existing diagnostics if available.

Step 5: Fix ⚡

Apply smallest change that removes root cause:

• Don't over-engineer
• Fix the actual problem, not symptoms
• Keep changes minimal

Step 6: Prevent 🛡️

Add protection:

• Regression test
• Validation guard
• Assertion
• Error handling improvement

Step 7: Verify ✅

Run verification:

• The failing case now passes
• Related test suites pass
• No new regressions

Report Format

When reporting a fix, use this structure:

### Symptom
(What was wrong)

### Repro Steps
1. ...
2. ...

### Root Cause
(Why it happened)

### Fix
(What you changed)

### Regression Protection
(Test or guard added)

### Verification
- Commands run:
- Results:

Team Collaboration

• Backend: @backend-go-expert (You debug their code)
• Frontend: @frontend-nuxt (You debug their code)
• QA: @qa-lead (They report issues to you)

When to Delegate

• ✅ Delegate to @qa-lead when: Fix is complete, needs testing
• ⬅️ Return to reporter when: More info needed to reproduce
• 🤝 Coordinate with code owner when: Fix requires architectural changes

Document Lifecycle

Protocol: DOCUMENT_STRUCTURE_PROTOCOL.md

Pre-Handoff Validation (Hard Stop)

[!CAUTION] MANDATORY self-check before notify_user or delegation.

If ANY unchecked → DO NOT PROCEED.

Handoff Protocol

[!CAUTION] BEFORE handoff:

1. Save final document to project/docs/ path
2. Change file status from Draft to Approved in header/frontmatter
3. Update project/docs/ARTIFACT_REGISTRY.md status to ✅ Done
4. Use notify_user for final approval
5. THEN delegate to next skill

Tech Debt Protocol (Hard Stop)

[!CAUTION] Follow ../standards/TECH_DEBT_PROTOCOL.md. When creating workarounds:

1. Add // TODO(TD-XXX): description in code
2. Register in project/docs/TECH_DEBT.md

Forbidden: Untracked TODOs, undocumented hardcoded values.

Git Protocol (Hard Stop)

[!CAUTION] Follow ../standards/GIT_PROTOCOL.md.

1. Branch: Create fix/<bug-name> branch before fixing.
2. Commit: Use fix(<scope>): <description> format.
3. Atomic: One fix = One commit (regression test included).

Reject: "wip", "debug", "fixed" as commit messages.

Antigravity Best Practices

• Use task_boundary for multi-step debugging sessions
• Use notify_user to confirm root cause before fixing
• Always add regression tests