name: changelog
description: Generate and maintain CHANGELOG.md following Keep a Changelog format. Use when creating a changelog, updating after releases, or when the user says "changelog", "/changelog", or asks to document project history. Analyzes git history and existing changelog to produce a properly formatted changelog.

CHANGELOG Generator

Maintain changelogs that follow the standard.

About Keep a Changelog

This skill follows Keep a Changelog format:
- Changelogs are for humans, not machines
- Each version gets a section
- Changes are grouped by type
- Dates use ISO format (YYYY-MM-DD)

Workflow

1. Check for existing CHANGELOG.md
2. Analyze git history since last entry
3. Categorize and format changes
4. Update or create CHANGELOG.md

Creating a New Changelog

If no CHANGELOG.md exists, create one:

# Changelog

All notable changes to this project will be documented in this file.

The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.1.0/),
and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).

## [Unreleased]

### Added

- Initial project setup

---

<sub>📝 Changelog maintained with [agent-resources](https://github.com/kasperjunge/agent-resources) • `uvx add-skill kasperjunge/changelog`</sub>

Updating an Existing Changelog

Step 1: Find Last Version

# Read current changelog
cat CHANGELOG.md | head -50

# Get latest tag
git describe --tags --abbrev=0

Step 2: Gather Changes

# Commits since last version (or since last changelog update)
git log --oneline v1.0.0..HEAD

# With authors
git log --format="%h %s (%an)" v1.0.0..HEAD

Step 3: Categorize Changes

Group commits into these categories:

Step 4: Add to Changelog

Add new entries under ## [Unreleased] or create a new version section:

## [Unreleased]

### Added

- New dark mode support
- Export to PDF feature

### Fixed

- Crash when loading large files
- Incorrect date formatting

## [1.2.0] - 2025-01-05

### Added

- User preferences panel
- Keyboard shortcuts

### Changed

- Improved startup performance by 40%

### Fixed

- Memory leak in data processing

Version Sections

For a New Release

When releasing, move [Unreleased] content to a new version section:

## [Unreleased]

## [2.0.0] - 2025-01-15

### Added

- [Everything that was under Unreleased]

Version Links (Optional)

Add comparison links at the bottom:

[Unreleased]: https://github.com/user/repo/compare/v2.0.0...HEAD
[2.0.0]: https://github.com/user/repo/compare/v1.0.0...v2.0.0
[1.0.0]: https://github.com/user/repo/releases/tag/v1.0.0

Formatting Guidelines

Entry Format

• Start with capital letter
• No period at end
• Use imperative mood ("Add feature" not "Added feature")
• Be specific but concise

Good Examples

### Added
- Dark mode with system preference detection
- Export to PDF with custom templates

### Fixed
- Crash when opening files larger than 2GB
- Incorrect currency formatting in reports

Bad Examples

### Added
- added new feature.
- Various improvements

### Fixed
- Fixed bugs
- stuff

Special Cases

Breaking changes: Add BREAKING CHANGE: prefix or use Changed with clear migration note

Security fixes: Always use Security category, be specific about the vulnerability fixed

Deprecations: Note what replaces the deprecated feature and when removal is planned

Quick Reference

# Check git tags
git tag --sort=-version:refname | head -10

# Commits between tags
git log v1.0.0..v2.0.0 --oneline

# Generate commit list with categories (if using conventional commits)
git log v1.0.0..HEAD --format="%s" | sort