diff-analysis skill

---
name: diff-analysis
description: 'Use this skill for systematic change analysis with risk scoring. Use
  when analyzing specific changesets, assessing risk of changes, preparing release
  notes, categorizing changes by type and impact. Do not use when quick context catchup
  - use catchup instead. DO NOT use when: full PR review - use review-core with pensive
  skills.'
category: analysis-methods
tags:
- changes
- semantic-analysis
- risk-assessment
- categorization
- summaries
dependencies:
- imbue:evidence-logging
tools:
- git
- diff-tools
usage_patterns:
- change-analysis
- risk-assessment
- release-preparation
complexity: intermediate
progressive_loading: true
module_strategy: workflow-based
estimated_tokens: 800
---
## Table of Contents

- [Overview](#overview)
- [When to Use](#when-to-use)
- [Activation Patterns](#activation-patterns)
- [4-Step Methodology](#4-step-methodology)
- [Exit Criteria](#exit-criteria)
- [Troubleshooting](#troubleshooting)

# Diff Analysis Methodology

## Overview

Structured method for analyzing changesets: categorize changes, assess risks, generate insights. Works for git diffs, configuration changes, API migrations, schema updates, or document revisions.

## When To Use
- Extracting insights from raw change data
- Categorizing and prioritizing changes before code reviews
- Preparing release notes or changelogs
- Assessing migration scope and risk

## When NOT To Use

- Quick context catchup - use catchup instead
- Full PR review - use review-core with pensive skills

## Activation Patterns
**Trigger Keywords**: diff, changes, release notes, changelog, migration, impact, risk assessment

**Auto-Load When**: Git diffs present, change analysis requested, impact assessment needed.

## Progressive Loading

Load modules based on workflow stage:

### Always Load
- `modules/semantic-categorization.md` for change categorization workflow

### Conditional Loading
- `modules/risk-assessment-framework.md` when risk assessment is needed
- `modules/git-diff-patterns.md` when working with git repositories

### Integration
- Use `sanctum:git-workspace-review` for git data gathering
- Use `imbue:evidence-logging` for capturing analysis evidence
- Use `imbue:structured-output` for formatting final deliverables

## Required TodoWrite Items
1. `diff-analysis:baseline-established`
2. `diff-analysis:changes-categorized`
3. `diff-analysis:risks-assessed`
4. `diff-analysis:summary-prepared`

Mark each item complete as you finish the corresponding step.

## 4-Step Methodology

### Step 1: Establish Baseline (`diff-analysis:baseline-established`)
Define comparison scope: what states are being compared, boundary of analysis, and scale metrics.

For git contexts, load `modules/git-diff-patterns.md`. For other contexts, compare relevant artifacts.

### Step 2: Categorize Changes (`diff-analysis:changes-categorized`)
Group changes by semantic type. Load `modules/semantic-categorization.md` for change categories, semantic categories, and prioritization.

### Step 3: Assess Risks (`diff-analysis:risks-assessed`)
Evaluate impact. Load `modules/risk-assessment-framework.md` for risk indicators, levels, and scoring methodology.

### Step 4: Prepare Summary (`diff-analysis:summary-prepared`)
Synthesize findings: theme, scope with counts, risk level, review focus, dependencies. Format for downstream consumption (PR descriptions, release notes, reviews).

## Exit Criteria
- All TodoWrite items completed with categorized changes and risk assessment
- Downstream workflows have semantic understanding of the changeset
- Summary ready for appropriate consumption (review, release notes, planning)
## Troubleshooting

### Common Issues

**Command not found**
Ensure all dependencies are installed and in PATH

**Permission errors**
Check file permissions and run with appropriate privileges

**Unexpected behavior**
Enable verbose logging with `--verbose` flag