werner

Werner — Claude Code Plugin

A Claude Code plugin for session retrospectives, development principles, and code quality enforcement.

Werner helps you build a self-improving development workflow by:

• Automatically capturing retro-worthy observations at the end of sessions
• Providing a structured retrospective review and apply workflow
• Enforcing file size limits to prevent code bloat
• Shipping reusable development principles you can inject into any project

Installation

From GitHub marketplace

/plugin marketplace add kreuzhofer/claude-werner-plugin
/plugin install werner@kreuzhofer-plugins

Local development

claude --plugin-dir /path/to/claude-werner-plugin

Getting Started

After installing, run /werner:init in your project to:

1. Append development principles to your project's CLAUDE.md
2. Set up the .claude/retros/ directory for retrospectives

You can then customize the principles in CLAUDE.md for your project's specific needs.

Skills

/werner:init

Initialize a project with Werner's development principles and retro infrastructure.

• Appends a ## Development Principles section to CLAUDE.md (creates the file if needed)
• Creates .claude/retros/ directory with a .gitignore
• Safe to run multiple times — detects existing principles and asks before replacing

/werner:retro

Manage session retrospectives. Retros capture observations, friction points, and improvement ideas.

• /werner:retro or /werner:retro review — Review all open retros grouped by category
• /werner:retro create <slug> — Create a new retro entry
• /werner:retro apply <slug> — Apply a retro's suggested action (create skill, update CLAUDE.md, etc.)
• /werner:retro dismiss <slug> — Dismiss a retro with a reason

Retro categories:

Category	Meaning	Typical action
skill-candidate	Repetitive task pattern	Create a new skill
principle	Development principle to enforce	Add to CLAUDE.md or create a hook
workflow	Process improvement	Update settings or hooks
observation	Noteworthy pattern	Track or convert later
automation	Automatable task	Create a hook

/werner:bye

End-of-session wrap-up:

1. Summarizes what was accomplished
2. Shows count of pending retros
3. Offers to review retros or exit

Hooks

Retro Check (Stop event)

Fires at the end of sessions with sufficient substance (150+ transcript lines). Nudges Claude to silently evaluate whether any retro-worthy patterns occurred and create entries in .claude/retros/ if so.

File Size Enforcement (PostToolUse on Edit|Write)

Enforces line limits on source files to prevent code bloat:

• 400 lines for source files (.ts, .tsx, .js, .jsx, .py, .go, .rs, .java, .rb, .swift, .kt)
• 600 lines for test files (*.test.*, *.spec.*, *__tests__/*)
• Warns at 350+ lines
• Blocks when over the limit

Development Principles

The following principles are injected by /werner:init. They can be customized per project:

1. Test-Driven Development
2. Small, Reversible, Observable Changes
3. Fail Fast, No Silent Fallbacks
4. Minimize Complexity (YAGNI)
5. Deliberate Trade-offs (DRY with Restraint)
6. Don't Assume — Ask for Clarification
7. Confidence-Gated Autonomy
8. Security-by-Default
9. Don't Break Contracts
10. Risk-Scaled Rigor

Retro File Format

Retros are stored as markdown files in .claude/retros/:

---
date: 2026-04-11
status: open
category: workflow
severity: medium
---

## Observation
What was observed.

## Context
Why this matters.

## Suggested Action
Concrete next step.

License

MIT