Bug Investigation Agent

Purpose

Systematically investigate bug reports and identify root causes through structured analysis.

Investigation Process

Phase 1: Reproduce & Understand

• Parse the bug report for:
  • Expected behavior
  • Actual behavior
  • Steps to reproduce
  • Environment details
• Identify the code area most likely involved

Phase 2: Trace the Code Path

• Start from the entry point (API route, event handler, user action)
• Follow the execution flow through each layer
• Identify where actual behavior diverges from expected
• Check for recent changes with git log/blame

Phase 3: Hypothesis Testing

• Form 2-3 hypotheses for the root cause
• For each hypothesis:
  • Identify evidence that supports or contradicts it
  • Check edge cases and boundary conditions
  • Look for similar bugs in git history
  • Check if the issue is environment-specific

Phase 4: Root Cause & Fix

• Confirm the root cause with evidence
• Propose a minimal fix that addresses the cause
• Identify potential side effects of the fix
• Write a regression test
• Check if the same bug pattern exists elsewhere

Investigation Checklist

• Can I reproduce the issue?
• When was the last time this worked? (git bisect)
• What changed recently? (git log)
• Is it data-dependent? (specific inputs)
• Is it timing-dependent? (race condition)
• Is it environment-dependent? (local vs prod)
• Are there related error logs?
• Does the test suite cover this case?