name: debugger description: Systematic debugging skill. 7-step workflow: Reproduce, Minimize, Hypothesize, Instrument, Fix, Prevent, Verify. Activate when troubleshooting errors. version: 1.0.0

Debugger 🔍

Systematic problem-solving for runtime errors, failing tests, and unexpected behavior.

[!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"

Language Requirements

All skill files must be in English. See LANGUAGE.md.

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:

Most likely cause
Second candidate
Edge case possibility
(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

Iteration Protocol (Ephemeral → Persistent)

[!IMPORTANT] Phase 1: Draft in Brain — Create debug report as artifact. Iterate via notify_user. Phase 2: Persist on Approval — ONLY after fix verified → write to project/docs/bugs/

Artifact Ownership

Creates: project/docs/bugs/<issue-name>.md
Reads: Issue description, error logs, code
Updates: project/docs/ARTIFACT_REGISTRY.md (status + timestamp)

Pre-Handoff Validation (Hard Stop)

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

#	Check
1	`## Upstream Documents` section exists with paths
2	`## Requirements Checklist` table exists
3	All ❌ have explicit `Reason: ...`
4	Document in `review/` folder
5	`ARTIFACT_REGISTRY.md` updated

If ANY unchecked → DO NOT PROCEED.

Handoff Protocol

[!CAUTION] BEFORE handoff:

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

Tech Debt Protocol (Hard Stop)

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

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

Forbidden: Untracked TODOs, undocumented hardcoded values.

Git Protocol (Hard Stop)

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

Branch: Create fix/<bug-name> branch before fixing.
Commit: Use fix(<scope>): <description> format.
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

debugger

Installation

Details

Usage

Skill Instructions