---

name: error-recovery description: Expert knowledge in error diagnosis, debugging strategies, and self-healing patterns. Use when tasks fail or errors occur. allowed-tools: Read, Write, Edit, Bash, Glob, Grep

Error Recovery Skill

Comprehensive strategies for diagnosing, fixing, and preventing errors.

Error Classification

Compile-Time Errors

Runtime Errors

Build Errors

Test Failures

Recovery Strategies

Strategy 1: Auto-Fix (Lint/Format)

Copy# ESLint auto-fix
npx eslint . --fix

# Prettier format
npx prettier --write .

# TypeScript strict fixes
# Some can be auto-fixed with ts-fix

Strategy 2: Dependency Fix

Copy# Reinstall dependencies
rm -rf node_modules package-lock.json
npm install

# Update specific package
npm update package-name

# Fix peer dependencies
npm install --legacy-peer-deps

Strategy 3: Type Error Fix

Copy// TS2322: Type mismatch
// Before
const value: string = 123;
// After
const value: number = 123;

// TS2531: Possibly null
// Before
element.innerHTML = 'text';
// After
if (element) element.innerHTML = 'text';

// TS2339: Property missing
// Before
user.email
// After
if ('email' in user) user.email

Strategy 4: Runtime Error Fix

Copy// TypeError: Cannot read property of undefined
// Before
const name = user.profile.name;
// After
const name = user?.profile?.name ?? 'Unknown';

// ReferenceError: not defined
// Check: Is it imported?
// Check: Is it in scope?
// Check: Is it spelled correctly?

Strategy 5: Test Failure Fix

Copy// Assertion failure - debug first
console.log('Actual:', result);
console.log('Expected:', expected);

// Async timeout
test('async test', async () => {
  // Add proper awaits
  const result = await asyncOperation();
  expect(result).toBeDefined();
}, 10000); // Increase timeout if needed

// Mock not working
vi.mock('./module', () => ({
  default: vi.fn().mockReturnValue('mocked'),
}));

Recovery Protocol

Copy┌─────────────────────────────────────────┐
│           ERROR DETECTED                │
└─────────────────┬───────────────────────┘
                  ▼
┌─────────────────────────────────────────┐
│         1. CLASSIFY ERROR               │
│  Syntax | Type | Runtime | Build | Test │
└─────────────────┬───────────────────────┘
                  ▼
┌─────────────────────────────────────────┐
│         2. IDENTIFY FIX                 │
│   Auto-fix | Manual | Delegate          │
└─────────────────┬───────────────────────┘
                  ▼
┌─────────────────────────────────────────┐
│         3. APPLY FIX                    │
│   Make minimal, targeted change         │
└─────────────────┬───────────────────────┘
                  ▼
┌─────────────────────────────────────────┐
│         4. VERIFY FIX                   │
│   tsc && eslint && npm test             │
└─────────────────┬───────────────────────┘
                  ▼
        ┌─────────┴─────────┐
        │ Fixed?            │
        └─────────┬─────────┘
          Yes     │     No
           │      │      │
           ▼      │      ▼
        ┌─────┐   │   ┌─────────────────┐
        │ Done│   │   │ Increment retry │
        └─────┘   │   │ (max 3)         │
                  │   └────────┬────────┘
                  │            ▼
                  │   ┌─────────────────┐
                  │   │ Retry < 3?      │
                  │   └────────┬────────┘
                  │      Yes   │   No
                  │       │    │    │
                  │       ▼    │    ▼
                  │   ┌──────┐ │ ┌────────┐
                  └───│Retry │ │ │Escalate│
                      └──────┘ │ └────────┘

Prevention Strategies

1. TypeScript Strict Mode - Catch errors at compile time
2. ESLint Rules - Enforce best practices
3. Pre-commit Hooks - Validate before commit
4. Unit Tests - Catch regressions
5. Code Review - Human verification