Bug Investigation & Fix Planning
Investigate bugs from any input — error logs, stack traces, user reports. Creates an architectural fix plan with exact code specifications.
Use the right skill:
- Bug fixes →
bug(this skill) - Quick debugging →
debug - New features → plan via
/arc:core:plan - Code quality →
quality
Note: Only view-only git commands allowed (no state modifications).
Arguments
Takes any input:
- Error logs:
"TypeError: 'NoneType' at auth.py:45" - Stack traces:
"$(cat stacktrace.txt)" - Log files:
./logs/error.log - User reports:
"Login fails when user has no profile" - Diagnostic instructions:
"Check docker logs for api-service"
Instructions
Step 1: Process Input
Parse input:
- If file path → use Read tool to load contents
- If inline text → extract error signals
- If diagnostic instructions → execute via Bash:
- Docker logs:
docker logs <container> --tail 500 - Process logs:
journalctl -u <service>
- Docker logs:
Step 2: Launch Agent
Launch background agent with gathered context:
REQUIRED Task tool parameters:
subagent_type: "arc:bug-plan-creator"
run_in_background: true
prompt: "Investigate bug and create fix plan:\n\n<gathered context>"
Output a status message like "Investigating bug..." and end your turn. The system wakes you when the agent finishes.
Step 3: Report Result
## Bug Investigation Complete
**Plan**: openspec/plans/YY-MM-DD-bug-<name>-<hash5>.md
**Severity**: [Critical/High/Medium/Low]
**Root Cause Confidence**: [High/Medium/Low]
Root Cause: [file:line] - [brief description]
Next Steps:
1. Review the fix plan
2. Execute: `/arc:core:execute --source plan --plan-path <plan-path>`
Error Handling
| Scenario | Action |
|---|---|
| Log file missing | Report error, continue with other data |
| Diagnostic fails | Report error, continue |
| Low confidence | Highlight, recommend review |
| No bug found | Report external/config causes |