Error Debugger Skill | Agent Skills

Error Debugger

Purpose

Context-aware debugging that learns from past solutions. When an error occurs:

Searches memory for similar past errors
Analyzes error message and stack trace
Provides immediate fix with code examples
Creates regression test via testing-builder
Saves solution to memory for future

For ADHD users: Eliminates debugging frustration - instant, actionable fixes. For SDAM users: Recalls past solutions you've already found. For all users: Gets smarter over time as it learns from your codebase.

Activation Triggers

User says: "debug this", "fix this error", "why is this failing"
Error messages containing: TypeError, ReferenceError, SyntaxError, ECONNREFUSED, CORS, 404, 500, etc.
Stack traces pasted into conversation
"Something's broken" or similar expressions

Core Workflow

1. Parse Error

Extract key information:

{
  error_type: "TypeError|ReferenceError|ECONNREFUSED|...",
  message: "Cannot read property 'map' of undefined",
  stack_trace: [...],
  file: "src/components/UserList.jsx",
  line: 42,
  context: "Rendering user list"
}

2. Search Past Solutions

Query context-manager:

search memories for:
- error_type match
- similar message (fuzzy match)
- same file/component if available
- related tags (if previously tagged)

If match found:

🔍 Found similar past error!

📝 3 months ago: TypeError in UserList component
✅ Solution: Added null check before map
⏱️ Fixed in: 5 minutes
🔗 Memory: procedures/{uuid}.md

Applying the same solution...

If no match:

🆕 New error - analyzing...
(Will save solution after fix)

3. Analyze Error

See reference.md for comprehensive error pattern library.

Quick common patterns:

TypeError: Cannot read property 'X' of undefined → Optional chaining + defaults
ECONNREFUSED → Check service running, verify ports
CORS errors → Configure CORS headers
404 Not Found → Verify route definition
500 Internal Server Error → Check server logs

4. Provide Fix

Format:

🔧 Error Analysis

**Type**: {error_type}
**Location**: {file}:{line}
**Cause**: {root_cause_explanation}

**Fix**:

```javascript
// ❌ Current code
const users = data.users;
return users.map(user => <div>{user.name}</div>);

// ✅ Fixed code
const users = data?.users || [];
return users.map(user => <div>{user.name}</div>);

Explanation: Added optional chaining and default empty array to handle case where data or data.users is undefined.

Prevention: Always validate API response structure before using.

Next steps:

Apply the fix
Test manually
I'll create a regression test


### 5. Save Solution

After fix confirmed working:

```bash
# Save to context-manager as PROCEDURE
remember: Fix for TypeError in map operations
Type: PROCEDURE
Tags: error, typescript, array-operations
Content: When getting "Cannot read property 'map' of undefined",
         add optional chaining and default empty array:
         data?.users || []

Memory structure:

# PROCEDURE: Fix TypeError in map operations

**Error Type**: TypeError
**Message Pattern**: Cannot read property 'map' of undefined
**Context**: Array operations on potentially undefined data

## Solution

Use optional chaining and default values:

```javascript
// Before
const items = data.items;
return items.map(...)

// After
const items = data?.items || [];
return items.map(...)

When to Apply

API responses that might be undefined
Props that might not be passed
Array operations on uncertain data

Tested

✅ Fixed in UserList component (2025-10-17) ✅ Regression test: tests/components/UserList.test.jsx

Tags

error, typescript, array-operations, undefined-handling


### 6. Create Regression Test

Automatically invoke testing-builder:

create regression test for this fix:

Test that component handles undefined data
Test that component handles empty array
Test that component works with valid data


## Tool Persistence Pattern (Meta-Learning)

**Critical principle from self-analysis**: Never give up on first obstacle. Try 3 approaches before abandoning a solution path.

### Debugging Tools Hierarchy

When debugging an error, try these tools in sequence:

**1. Search Past Solutions (context-manager)**
```bash
# First approach: Check memory
search memories for error pattern

If no past solution found → Continue to next approach

2. GitHub Copilot CLI Search

# Second approach: Search public issues
copilot "Search GitHub for solutions to: $ERROR_MESSAGE"

If Copilot doesn't find good results → Continue to next approach

3. Web Search with Current Context

# Third approach: Real-time web search
[Use web search for latest Stack Overflow solutions]

If web search fails → Then ask user for more context

Real Example from Meta-Analysis

What happened: Tried GitHub MCP → Got auth error → Immediately gave up

What should have happened:

Try GitHub MCP → Auth error
Try gh CLI → Check if authenticated
Try direct GitHub API → Use personal token
Then create manual instructions if all fail

Outcome: The gh CLI WAS authenticated and worked perfectly. We gave up too early.

Applying This to Error Debugging

When fixing an error:

// Pattern: Try 3 fix approaches
async function debugError(error) {
  // Approach 1: Past solution
  const pastFix = await searchMemories(error);
  if (pastFix?.success_rate > 80%) {
    return applyPastFix(pastFix);
  }

  // Approach 2: Pattern matching
  const commonFix = matchErrorPattern(error);
  if (commonFix) {
    return applyCommonFix(commonFix);
  }

  // Approach 3: External search (Copilot/Web)
  const externalSolution = await searchExternalSolutions(error);
  if (externalSolution) {
    return applyExternalSolution(externalSolution);
  }

  // Only NOW ask for more context
  return askUserForMoreContext(error);
}

Integration Tool Persistence

When integrations are available, use them in this order:

For Error Search:

GitHub Copilot CLI → Search issues in your repos and similar projects
Local memory → Past solutions you've saved
Web search → Latest Stack Overflow/docs

For Solutions:

Past solution from memory (fastest)
Codegen-ai agent (if complex bug) → Automated PR
Jules CLI async task (if time-consuming fix)
Manual fix with code examples

Metrics

Track debugging approach success:

{
  "error_id": "uuid",
  "approaches_tried": [
    {"type": "memory_search", "result": "no_match"},
    {"type": "copilot_search", "result": "success", "time": "5s"},
    {"type": "applied_fix", "verified": true}
  ],
  "total_time": "30s",
  "lesson": "Copilot found solution on second try"
}

Key insight: Most "failed" approaches are actually "didn't try enough" approaches.

Context Integration

Query Past Solutions

Before analyzing new error:

// Search context-manager
const pastSolutions = searchMemories({
  type: 'PROCEDURE',
  tags: [errorType, language, framework],
  content: errorMessage,
  fuzzyMatch: true
});

if (pastSolutions.length > 0) {
  // Show user the past solution
  // Ask if they want to apply it
  // If yes, apply and test
  // If no, analyze fresh
}

Learning Over Time

Track which solutions work:

{
  solution_id: "uuid",
  error_pattern: "TypeError.*map.*undefined",
  times_applied: 5,
  success_rate: 100%,
  last_used: "2025-10-15",
  avg_fix_time: "2 minutes"
}

Sort solutions by success rate when multiple matches found.

Project-Specific Patterns

Some errors are project-specific:

// BOOSTBOX-specific
Error: "Boost ID not found"
→ Solution: Check boost exists before processing

// Tool Hub-specific
Error: "Tool not installed"
→ Solution: Run tool installer first

// Save these as PROJECT-specific procedures

Integration with Other Skills

Testing Builder

After providing fix:

Automatically invoke: testing-builder
Create regression test for: {error_scenario}
Ensure test fails without fix, passes with fix

Context Manager

Query for similar errors:

search memories for:
- PROCEDURE type
- Error tag
- Similar message
- Same file/component

Save new solutions:

Save as PROCEDURE:
- Error pattern
- Solution
- Code examples
- Tested timestamp

Rapid Prototyper

For complex fixes:

If fix requires significant refactoring:
→ Invoke rapid-prototyper
→ Create isolated example showing fix
→ User validates before applying to codebase

Additional Resources

Error Pattern Library - Comprehensive patterns for JavaScript, Network, Database, React errors
Debugging Examples - Step-by-step debugging workflow examples

Quick Reference

Common Error Patterns

| Error | Quick Fix | |-------|-----------| | undefined.map | data?.array || [] | | X is not a function | Check function exists | | ECONNREFUSED | Check service running | | CORS | Configure CORS headers | | 404 | Verify route exists | | 500 | Check server logs | | Timeout | Increase timeout value | | Cannot find module | Install dependency |

Trigger Phrases

"debug this"
"fix this error"
"why is this failing"
"something's broken"
[paste error message]
[paste stack trace]

File Locations

Past solutions: /home/toowired/.claude-memories/procedures/
Error patterns: Tagged with "error" in memory index

Success Criteria

✅ Common errors fixed instantly (<30 seconds) ✅ Past solutions automatically recalled ✅ All fixes include code examples ✅ Regression tests created automatically ✅ Solutions saved for future reference ✅ Debugging gets faster over time

Agent Skills: Error Debugger

Skill Files