Code Debugging

Fix broken story implementations using a systematic 5-step debugging ladder. Each step applies a specific debugging technique with increasing sophistication.

When to Use

Use this skill when:

• A story is at implementing (broken) stage
• Implementation failed with status: partial or status: failed
• Tests are failing after an implementation attempt

The 5-Step Debug Ladder

Step 1: code-sentinel       → Known anti-patterns
Step 2: root-cause-tracing  → Trace backward to source
Step 3: librarian agent     → Research outdated APIs
Step 4: Opus 4.5            → Fresh analysis
Step 5: systematic-debugging → Full 4-phase framework
   ↓
Escalate → implementing (escalated)

Each step is attempted in order. If a step fixes the issue, implementation is retried. If all 5 steps fail, the story is escalated for human review.

Step 1: Code Sentinel

Tool: Skill(skill="code-sentinel")

Check for known anti-patterns that cause test failures:

1. Run pytest tests/test_code_patterns.py -v
2. If tests fail, read the anti-pattern file for each failure
3. Apply the documented fix
4. Verify tests pass

Exit condition: All pattern tests pass → retry implementation

Step 2: Root Cause Tracing

Tool: Skill(skill="superpowers:root-cause-tracing")

Trace the error backward to find its source:

1. Capture the error — Get full stack trace and error message
2. Trace data flow — Follow variables backward from error point
3. Identify mutation — Find where data changed unexpectedly
4. Fix at source — Correct the root cause, not symptoms

Key Questions:

• What value was expected vs. actual?
• Where did this value come from?
• What transformed it along the way?

Exit condition: Root cause fixed → retry implementation

Step 3: Librarian Agent

Tool: Task(subagent_type="general-purpose") with web search

Research outdated APIs, version mismatches, or deprecated patterns:

1. Identify the API/library — What external dependency is involved?
2. Check version — Is the installed version current?
3. Search for changes — Look for breaking changes, deprecations
4. Update code — Apply modern patterns from current docs

Prompt template:

Research the error: "[ERROR MESSAGE]"

Check if this relates to:
1. Deprecated API patterns
2. Version mismatches
3. Breaking changes in recent releases

Search the official documentation and provide:
1. The correct modern pattern
2. Migration steps if needed

Exit condition: API updated to current pattern → retry implementation

Step 4: Opus 4.5 Fresh Analysis

Tool: Claude Opus 4.5 with optimized handover prompt

Get a fresh perspective with the most capable model:

1. Prepare handover — Key context only, not full chat history
2. Include specifics:
   • Exact error message and stack trace
   • What has been tried (steps 1-3)
   • Relevant code snippets
   • Test file and line numbers
3. Request targeted fix — Ask for specific code changes

Handover format:

## Context
Story [ID] implementation failed at [stage].

## Error
[Exact error message and stack trace]

## Previous Attempts
1. code-sentinel: [result]
2. root-cause-tracing: [result]
3. librarian agent: [result]

## Relevant Code
[Key snippets only]

## Request
Analyze the error and provide specific code fixes.

Exit condition: Opus fix applied → retry implementation

Step 5: Systematic Debugging

Tool: Skill(skill="superpowers:systematic-debugging")

Full 4-phase debugging framework as final attempt:

Phase 1: Reproduce

• Isolate the minimal failing case
• Ensure consistent reproduction

Phase 2: Diagnose

• Add logging at key points
• Use debugger/breakpoints
• Binary search for error location

Phase 3: Fix

• Apply minimal targeted fix
• Don't refactor unrelated code
• Document why fix works

Phase 4: Verify

• Confirm original test passes
• Run related tests
• Check for regressions

Exit condition: Fix verified → retry implementation

Step 6: Escalate

If all 5 steps fail:

1. Update story status:

   UPDATE story_nodes
   SET hold_reason = 'escalated',
       debug_attempts = 5
   WHERE id = '[story_id]';
   

2. Create escalation summary:

   ## Escalation: Story [ID]
   
   ### Error
   [Final error state]
   
   ### Debug Attempts
   1. code-sentinel: [result]
   2. root-cause-tracing: [result]
   3. librarian agent: [result]
   4. Opus 4.5: [result]
   5. systematic-debugging: [result]
   
   ### Recommendation
   [What human should investigate]
   

3. Notify — Post to story's GitHub issue

Workflow Integration

The debug orchestrator is invoked by new-0rchestrator.yml when:

# Query for broken stories
SELECT id, title, debug_attempts
FROM story_nodes
WHERE stage = 'implementing'
  AND hold_reason = 'broken'
  AND debug_attempts < 5
ORDER BY updated_at ASC
LIMIT 1;

After each debug attempt:

# Update attempt counter
UPDATE story_nodes
SET debug_attempts = debug_attempts + 1,
    updated_at = datetime('now')
WHERE id = '[story_id]';

Database Fields

Example Usage

# Pseudo-code for debug orchestrator invocation

story = get_broken_story()
attempt = story.debug_attempts + 1

if attempt == 1:
    result = run_code_sentinel(story)
elif attempt == 2:
    result = run_root_cause_tracing(story)
elif attempt == 3:
    result = run_librarian_agent(story)
elif attempt == 4:
    result = run_opus_analysis(story)
elif attempt == 5:
    result = run_systematic_debugging(story)
else:
    escalate(story)
    return

if result.success:
    story.hold_reason = None  # Clear broken hold
    story.debug_attempts = 0   # Reset counter
    retry_implementation(story)
else:
    story.debug_attempts = attempt
    save(story)