| name | claude-debug |
| description | Send a bug or failing test to Claude Code for root-cause analysis and fix. Use when you've hit an error you can't trace, a test is failing for unclear reasons, or a behavior is wrong and the cause is deep in the codebase. |
| version | 0.2.0 |
Claude Debug
Delegate a debugging session to Claude Code — Claude traces the root cause and applies a fix.
When to Use
- When a test is failing and the cause is unclear
- When asked to "have Claude debug this"
- When an error trace points deep into framework code or a complex call chain
- When you've already tried the obvious fixes and need fresh eyes
Call Pattern
Step 1: Send the bug report
mcp__claude-code__claude_code:
prompt: |
Debug the following issue and fix it.
SYMPTOM: {error message, failing test name, or wrong behavior description}
ERROR OUTPUT:
```
{paste stack trace or test output here}
```
REPRODUCTION STEPS: {how to reproduce — command to run, inputs, etc.}
WHAT I TRIED: {optional — what you already ruled out}
Instructions:
1. Read the source files involved in the reported code flow
2. Identify the root cause (not just where it crashes — why)
3. Apply a minimal, correct fix
4. Run the failing test/command to confirm the fix works
5. Check for regressions in related tests
6. Report: root cause, fix applied, verification result
PROVENANCE NOTE: The code being debugged was written by OpenAI Codex. Evaluate
with full rigor — do not assume Codex's code is correct anywhere adjacent to the
reported bug. Check surrounding logic independently.
cwd: {project working directory}
effort: high
Save the returned session_id as {debug_session_id}.
Step 2: Follow up
If Claude identified the root cause but couldn't fix it cleanly, or found related issues:
mcp__claude-code__claude_code_reply:
session_id: {debug_session_id}
prompt: "You identified the root cause in parseConfig(). Also check validateConfig() — it has a similar pattern."
Output Format
Report to the user:
- Root cause (one sentence)
- Fix applied (file:line, what changed)
- Verification result (test output)
- Any adjacent issues Claude found
Notes
- Always pass the exact error output — Claude needs the full stack trace, not a summary
effort: high is important for non-obvious bugs; shallow effort stops at symptoms
- If Claude can't reproduce the bug, ask it to add diagnostic logging first, then re-run
permissionMode defaults to default (allows writes) — Claude will apply the fix directly
Related Skills
claude-plan — use before debugging to sketch a diagnosis strategy for complex, multi-file issues
claude-implement — use after root cause is identified to apply a larger fix or refactor
$audit-fix — use when the bug is a pattern across many files and needs a full audit→fix cycle