# Ponytail

> An open-source plugin that makes AI coding agents write minimal, YAGNI-first code — like the laziest senior dev in the room.

Ponytail is an open-source MIT-licensed plugin for AI coding agents, created by DietrichGebert on GitHub. It injects a strict minimalism ruleset into agents like Claude Code, Codex, Gemini CLI, and others, pushing them to write the least code that actually works. The project reached v4.7.0 in June 2026 and has accumulated over 25,000 GitHub stars since its creation on June 12, 2026.

## What It Is

Ponytail is an agent skill/plugin that embeds a "lazy senior developer" decision ladder into AI coding agents. Before writing any code, the agent is instructed to stop at the first rung that satisfies the task: skip it entirely (YAGNI), use stdlib, use a native platform feature, use an installed dependency, write one line, or only then write the minimum that works. The result, according to the project's own benchmarks, is 80–94% less code, 3–6× faster task completion, and 47–77% lower API cost compared to a no-skill baseline — measured across Claude Haiku, Sonnet, and Opus over five everyday tasks and ten runs per cell.

## How the Ruleset Works

The core mechanic is a six-rung decision ladder injected as always-on context every agent session:

- **Rung 1 – YAGNI**: Does this need to exist? If not, skip it.
- **Rung 2 – Stdlib**: Does the standard library cover it? Use it.
- **Rung 3 – Native platform**: Is there a built-in browser or OS feature? Use it.
- **Rung 4 – Installed dependency**: Is something already in the project? Use it.
- **Rung 5 – One line**: Can it be done in one line? Write one line.
- **Rung 6 – Minimum viable**: Only then write the smallest thing that works.

Every shortcut the agent takes is marked in the output with a `ponytail:` comment naming its upgrade path, so technical debt is explicit and trackable. The `/ponytail-debt` command harvests those comments into a ledger.

## Agent Portability and Platform Support

The README states Ponytail works with 13 agents. Installation paths include:

- **Claude Code**: `/plugin marketplace add` + `/plugin install`
- **Codex**: `codex plugin marketplace add` (also covers the Codex desktop app)
- **GitHub Copilot CLI**: `copilot plugin marketplace add`
- **Gemini CLI / Antigravity CLI**: `gemini extensions install` or `agy plugin install`
- **Pi agent harness**: `pi install git:github.com/DietrichGebert/ponytail`
- **OpenCode**: plugin field in `opencode.json`
- **OpenClaw**: `clawhub install ponytail`
- **Cursor, Windsurf, Cline, Aider, Kiro, GitHub Copilot (editor)**: copy the matching rules file from the repo (instruction-only mode, no slash commands)

## Commands

Skill-capable hosts (Claude Code, Codex, OpenCode, Gemini, Pi) get a set of slash commands:

| Command | Purpose |
|---|---|
| `/ponytail [lite\|full\|ultra\|off]` | Set intensity or report current level |
| `/ponytail-review` | Review current diff for over-engineering |
| `/ponytail-audit` | Audit the whole repo, not just the diff |
| `/ponytail-debt` | Harvest deferred `ponytail:` shortcuts into a ledger |
| `/ponytail-help` | Quick command reference |

The default mode is `full`; it can be overridden per-session or globally via the `PONYTAIL_DEFAULT_MODE` env var or `~/.config/ponytail/config.json`.

## Update: v4.7.0 — OpenClaw Support

The latest release, v4.7.0 ("lazy in OpenClaw now"), was published on June 16, 2026 — four days after the repository was created. The rapid release cadence and 25,000+ stars within days of launch signal strong early traction in the AI developer tooling space. The v4.7.0 release adds OpenClaw/ClawHub as a supported install target, with the `.openclaw/skills/` package generated from the `skills/` directory via a build script.

## Features
- YAGNI-first decision ladder injected into AI agents
- 80-94% less generated code vs no-skill baseline
- 3-6x faster task completion on Claude API
- 47-77% lower API cost per task
- Works with 13 AI agents and coding tools
- Always-on ruleset injection every session
- ponytail: comments mark every shortcut with upgrade path
- /ponytail-review command for diff-level over-engineering review
- /ponytail-audit command for whole-repo audit
- /ponytail-debt command to harvest deferred shortcuts into a ledger
- lite/full/ultra/off intensity levels
- PONYTAIL_DEFAULT_MODE env var for global default
- Trust-boundary validation and security never skipped
- Benchmarks reproducible via promptfoo

## Integrations
Claude Code, Codex, GitHub Copilot CLI, Gemini CLI, Antigravity CLI, Pi agent harness, OpenCode, OpenClaw / ClawHub, Cursor, Windsurf, Cline, Aider, Kiro, GitHub Copilot (editor)

## Platforms
WINDOWS, API, VSC_EXTENSION, DEVELOPER_SDK, CLI

## Pricing
Open Source

## Version
v4.7.0

## Links
- Website: https://github.com/DietrichGebert/ponytail
- Documentation: https://github.com/DietrichGebert/ponytail/blob/main/docs/agent-portability.md
- Repository: https://github.com/DietrichGebert/ponytail
- EveryDev.ai: https://www.everydev.ai/tools/ponytail