Codex Debug Skill

Systematic debugging and root cause analysis with Codex (gpt-5.2).

When to Use

• Debugging complex bugs
• Finding root causes of issues
• Investigating mysterious errors
• Performance issue diagnosis
• Race conditions or timing issues

Reasoning Level

xhigh (debugging requires deep analysis)

Execution

1. Gather all relevant information:
   • Error messages
   • Stack traces
   • Relevant code files
   • Reproduction steps
2. Formulate a debugging prompt:
   Copy

   Debug this issue systematically.
   
   Issue: <description>
   
   Error/Symptoms:
   <error messages, behavior>
   
   Relevant Code:
   <file contents>
   
   Please:
   1. Identify possible causes
   2. Analyze each potential root cause
   3. Determine the most likely cause
   4. Suggest a fix
   

3. Run: codex exec -c model_reasoning_effort="xhigh" "<prompt>"
4. Return the debugging analysis with fix recommendation

Response Format

**Codex Debug Analysis:**

**Issue Summary:**
[What's happening]

**Root Cause Investigation:**
[Step-by-step analysis of potential causes]

**Most Likely Cause:**
[Primary hypothesis with evidence]

**Recommended Fix:**
[Specific fix with code if applicable]

**Session ID:** [id]