Patch Design Skill

Create minimal, surgical patch plans for targeted fixes.

When to Use

• Fixing specific issues from review
• Creating focused bug fixes
• Addressing blockers without scope creep
• Making targeted improvements

Core Principle

"This is a PATCH - keep the scope minimal. Only fix what's described in the issue and nothing more."

Design Workflow

Step 1: Understand the Specific Issue

Parse the issue clearly:

• What is broken? (specific behavior)
• How should it work? (expected behavior)
• What evidence exists? (screenshots, errors)

Do NOT expand scope beyond the reported issue.

Step 2: Analyze Current State

Review the relevant code:

# Find relevant files
git diff --stat
grep -r "related_function" src/

# Read the specific code
cat src/component/file.ts

Step 3: Determine Minimum Fix

Ask: "What is the smallest change that fixes this?"

Approach	Lines	Risk
Surgical fix	1-10	Low
Targeted fix	10-50	Medium
Refactor	50+	High

Always prefer surgical fixes for patches.

Step 4: Create Patch Plan

Document the precise fix:

# Patch: [Concise title]

## Issue Summary
**Problem**: [What's broken]
**Solution**: [Minimal fix]

## Files to Modify
- `path/to/file.ts`: [Specific change]

## Implementation Steps

### Step 1: [Specific action]
[Exact code change]

### Step 2: [Specific action]
[Exact code change]

## Validation
- [Command to verify fix]
- [How to confirm success]

## Patch Scope
- Lines of code: ~X
- Risk level: low
- Testing: [minimal/standard]

Step 5: Define Validation

Every patch needs verification:

## Validation

1. Run specific test: `npm test path/to/test`
2. Manual verification: [steps]
3. Visual check: [if applicable]

Patch Plan Template

# Patch: [Brief description]

## Metadata
- Issue: [Source of this patch request]
- Severity: [blocker/tech_debt]

## Issue Summary
**Original Spec**: [Link if available]
**Problem**: [Brief description of what's wrong]
**Solution**: [Brief description of the fix]

## Files to Modify
[Only files that need changes - be specific]

- `src/component/Button.tsx`: Fix disabled state

## Implementation Steps

IMPORTANT: Execute every step in order.

### Step 1: [Specific change]

<!-- markdownlint-disable MD033 -->

```jsx
// Before
<button onClick={handleClick}>

// After
<button onClick={handleClick} disabled={isLoading}>

Step 2: [Next change if needed]

[Details]

Validation

Execute to confirm patch is complete:

• npm test src/component/Button.test.tsx
• Manual: Click button, verify disabled during load

Patch Scope

• Lines changed: ~5
• Risk level: low
• Testing: Run component tests

Anti-Patterns to Avoid

Scope Creep

# BAD: Expanding scope
While fixing the button, I noticed the form could use
refactoring, so I'll also update the validation logic,
improve the error messages, and add loading states to
all other buttons too.

Vague Changes

# BAD: Vague plan
## Implementation
- Fix the button issue
- Make it work correctly
- Test to confirm

No Validation

# BAD: No verification
## Implementation
1. Change the code
2. Done

Best Practices

1. One issue, one patch: Don't bundle fixes
2. Minimal scope: Only change what's needed
3. Specific steps: Exact code changes
4. Clear validation: How to verify success
5. Risk assessment: Lines changed, testing needed

Integration with Review

Patches typically come from review issues:

/review → Identifies blocker
  ↓
/patch → Creates surgical fix plan
  ↓
/implement → Executes patch
  ↓
/review → Verifies fix (re-review)

Memory References

• @issue-severity-classification.md - What triggers patches
• @review-vs-test.md - Review identifies patch needs
• @one-agent-one-purpose.md - Patches are focused by nature

Version History

• v1.0.0 (2025-12-26): Initial release

---

Last Updated

Date: 2025-12-26 Model: claude-opus-4-5-20251101