SKILL.md (this file): Main instructions and MANDATORY workflow
examples.md: Usage scenarios with different diff types
Context: Git domain context loaded via contextProvider.getDomainIndex("git"). See ContextProvider Interface.
- git_diff_reference.md: Unified diff format reference and best practices
- diff_patterns.md: Common patterns to identify in code changes
Memory: Project-specific memory accessed via memoryStore.getSkillMemory("get-git-diff", "{project-name}"). See MemoryStore Interface.
scripts/:
- README.md: Complete documentation for all helper scripts
- validate.sh: Git repository and commit validation functions
- commit_info.sh: Commit metadata retrieval (hash, author, date, message)
- diff_stats.sh: Diff statistics and line count analysis
- file_operations.sh: File operation detection (add, modify, delete, rename)
- utils.sh: General utilities (branch detection, formatting, repo info)
templates/:
- output_template.md: Standard output format template

Analysis Focus Areas

Git diff analysis evaluates 7 critical dimensions:

Change Scope: Files affected, lines modified, overall impact radius
Change Type: Feature addition, bug fix, refactoring, configuration change
Structural Changes: File renames, moves, deletions, additions
Risk Assessment: Breaking changes, API modifications, database migrations
Code Quality Impact: Complexity changes, test coverage changes
Merge Conflicts: Merge commit analysis, conflict resolution patterns
Performance Impact: Algorithm changes, database query modifications, resource usage

Note: Analysis depth is summary-level, focusing on what changed and high-level impact.

MANDATORY WORKFLOW (MUST FOLLOW EXACTLY)

� STEP 1: Commit Identification (REQUIRED)

YOU MUST:

Check if commit hashes/branch names were provided in the triggering prompt
If NOT provided, ask the user with these options:
- Option A: Compare specific commit hashes (ask for two commit SHAs)
- Option B: Compare HEAD of current branch to main/master
- Option C: Compare two branch names
- Option D: Compare current changes to a specific commit
Validate that provided commits/branches exist in the repository
Use git rev-parse to verify and get full commit hashes
Get commit metadata (author, date, message) for both commits

DO NOT PROCEED WITHOUT VALID COMMITS

⚠️ STEP 2: Load Context & Memory, Then Execute Git Diff (REQUIRED)

FIRST: Load indexes and memory to understand available resources

Load domain index: Use contextProvider.getDomainIndex("git") to discover available git context files
Load skill memory: Use memoryStore.getSkillMemory("get-git-diff", "{project-name}") to load project-specific patterns
- If memory exists: Review project patterns from previous analyses
- If not: Note this is first analysis of this project

THEN: Execute git diff with special handling

Execute git diff [commit1]...[commit2] to get the unified diff
Check for and handle special cases:
- Large diffs (>1000 lines): Warn user, offer to summarize only or proceed
- Renamed files: Use git diff -M to detect renames
- Merge commits: Use git diff [commit]^...[commit] for merge commit analysis
- Binary files: Note binary file changes separately
Get diff statistics with git diff --stat
Get file list with git diff --name-status to identify A/M/D/R operations

DO NOT SKIP SPECIAL CASE DETECTION

� STEP 3: Analyze and Summarize (REQUIRED)

FIRST: Load relevant context files (use indexes from Step 2 for guidance)

Load context: Use contextProvider.getConditionalContext("git", detection) to load relevant context files (git_diff_reference.md, diff_patterns.md)

THEN: Analyze and document:

Commit Metadata:
- Commit hashes (full and short)
- Author and date for both commits
- Commit messages
- Number of commits between the two refs (if applicable)
Change Statistics:
- Total files changed
- Total insertions (+)
- Total deletions (-)
- Net change
File Operations:
- Added files (A)
- Modified files (M)
- Deleted files (D)
- Renamed files (R) - show old vs new
- Copied files (C)
Change Categorization:
- Group files by type (source code, tests, docs, config)
- Identify potential areas of impact
- Flag potentially risky changes
Special Notes:
- Merge commit indicator (if applicable)
- Large diff warning (if >1000 lines)
- Binary file changes
- Submodule changes

DO NOT SKIP ANALYSIS

� STEP 4: Generate Output & Update Project Memory (REQUIRED)

YOU MUST:

Use the template from templates/output_template.md
Create filename: diff_{short_hash1}_{short_hash2}.md
Include all components:
- Header with commit information
- Summary section with all statistics and analysis
- Full unified diff wrapped in markdown code blocks
Save to /claudedocs/ directory
Confirm file was written successfully

Output Format Requirements:

Unified diff must be in triple-backtick code blocks with diff language tag
Summary must be in clear markdown sections
File paths must use code formatting
Statistics must be in tables or lists
All sections must be clearly labeled

DO NOT OMIT ANY REQUIRED SECTIONS

OPTIONAL: Update Project Memory

If patterns emerge during analysis, consider storing insights via memoryStore.update("get-git-diff", "{project-name}", ...):

Common file change patterns
Frequently modified areas
Notable commit patterns or conventions

Special Case Handling

Large Diffs (>1000 lines)

When encountering large diffs:

Calculate total line count
Warn user: "This diff contains [N] lines across [M] files"
Ask user: "Would you like to proceed with full diff or summary only?"
If summary only:
- Include all metadata and statistics
- List all changed files with their line counts
- Omit the detailed unified diff
- Note: "Full diff omitted due to size. Use git diff [hash1]...[hash2] to view."

Renamed/Moved Files

For file renames:

Use git diff -M flag to detect renames (default similarity index: 50%)
In summary, clearly show: old/path/file.py � new/path/file.py
Indicate if content was also modified: R+M (renamed and modified)
In unified diff, show rename header: rename from/to

Merge Commits

For merge commits:

Detect with git rev-list --merges
Note in summary: "This is a merge commit"
Show both parent commits
Use git diff [commit]^...[commit] to show changes introduced by merge
Optionally offer to show diff against each parent separately

Compliance Checklist

Before completing ANY diff analysis, verify:

Step 1: Commits identified and validated
Step 2: Git diff executed with special case detection
Step 3: Complete analysis with all statistics and categorization
Step 4: Output generated in correct format and saved to /claudedocs

FAILURE TO COMPLETE ALL STEPS INVALIDATES THE ANALYSIS

Output File Naming Convention

Format: diff_{short1}_{short2}.md

Where:

{short1} = First 7 characters of first commit hash
{short2} = First 7 characters of second commit hash

Examples:

diff_a1b2c3d_e4f5g6h.md (commit to commit)
diff_main_feature-branch.md (branch comparison, if hashes not available)

Alternative for branches: If comparing branch tips, you may use branch names if they're short and filesystem-safe.

Git Commands Reference

Core Commands Used:

# Get commit info
git rev-parse [commit]
git log -1 --format="%H|%h|%an|%ae|%ad|%s" [commit]

# Generate diff
git diff [commit1]...[commit2]
git diff --stat [commit1]...[commit2]
git diff --name-status [commit1]...[commit2]
git diff -M [commit1]...[commit2]  # Detect renames

# Special cases
git rev-list --merges [commit]  # Check if merge commit
git diff [commit]^1..[commit]   # Merge commit against first parent

Version History

v1.2.0 (2026-02-10): Migrated to interface-based context and memory access
- Replaced hardcoded context paths with ContextProvider interface calls
- Replaced hardcoded memory paths with MemoryStore interface calls
- Added references to interface documentation
v1.1.0 (2025-01-XX): Centralized context and project memory
- Context files moved to shared git domain context
- Project-specific memory system added for get-git-diff skill
- Optional memory updates for common patterns
v1.0.0 (2025-11-13): Initial release
- Mandatory 4-step workflow
- Summary-level analysis with statistics
- Special handling for large diffs, renames, and merge commits
- Unified diff output to /claudedocs

get-git-diff

Git Diff Analyzer

� MANDATORY COMPLIANCE �

File Structure

� MANDATORY COMPLIANCE �