Workflow
Bug Fixing
Move from error trace to verified fix efficiently with root cause analysis and comprehensive testing.
Overview
Bug fixing with Claude Code moves from error diagnosis to verified fix in a single workflow. Instead of manually tracing through code and stack traces, describe the bug, provide error output, and let Claude analyze root causes, propose fixes, and validate the solution through tests.
Use this when investigating production issues, debugging test failures, fixing regressions, or addressing user-reported bugs. Especially valuable for unfamiliar codebases or complex error traces.
Step-by-step process
Provide complete context
Share the full error trace, reproduction steps, expected vs actual behavior, and any relevant logs. The more context, the faster the diagnosis.
Request root cause analysis
Ask Claude to identify the underlying issue, not just symptoms. Understanding why the bug exists prevents similar issues.
Review and apply fix
Claude proposes a fix with explanation. Review the approach, ensure it addresses the root cause, then apply the changes.
Verify with tests
Run existing tests and add new ones covering the bug scenario. Confirm the fix works and prevents regression.
Example prompts
"We're seeing crashes in production with this stack trace: [paste trace]. The error happens intermittently. What's the root cause and how can we fix it?"
"The integration test 'should process checkout' is failing with timeout error. Can you investigate the test, trace through the code, and identify why it's timing out?"
"API response times increased from 50ms to 2000ms after the last deploy. Profile the recent changes and identify the performance bottleneck."
"Users with names containing special characters can't sign up. The validation regex is rejecting valid names. Fix the regex and add test cases for international characters."
Expected outputs
Root cause analysis
Detailed explanation of why the bug occurs, including code paths, conditions, and contributing factors
Fix proposal with reasoning
Proposed code changes with rationale explaining why this approach solves the root cause
Test cases
New tests covering the bug scenario to prevent regression and validate the fix
Prevention recommendations
Suggestions for patterns or checks to avoid similar bugs in the future
Best practices
Common pitfalls
Fixing symptoms instead of root causes
Solution: Always ask 'why did this happen?' before implementing a fix. Trace back to the actual source
Skipping test verification
Solution: Never deploy a bug fix without running tests and confirming the issue is resolved
Not checking for similar bugs elsewhere
Solution: Ask: "Are there other places in the codebase with the same pattern that need fixing?"
Pro tips
Use git blame to add context
""Show me the git history for this function. When was this logic added and why?""
Compare with working scenarios
""This fails for API v2 but works for v1. What's different between the two implementations?""
Request multiple fix approaches
""Give me 2-3 different ways to fix this with tradeoffs for each approach""