Ponytail is a set of instructions and extensions that guides AI coding agents toward smaller, simpler code changes while retaining safety checks. It is intended for developers using agents such as Claude Code, and the catalogue entries are its skills, instructions, plugin, and rule.
Getting it into your agent
One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.
npx skills add DietrichGebert/ponytail --skill ponytail-gaingit clone --depth 1 https://github.com/DietrichGebert/ponytailWrote this? Show the measurements
A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.
[](https://agentmods.dev/skills/dietrichgebert/ponytail/ponytail-gain)<a href="https://agentmods.dev/skills/dietrichgebert/ponytail/ponytail-gain"><img src="https://agentmods.dev/badge/skills/dietrichgebert/ponytail/ponytail-gain/github.svg" alt="Measured on agentmods" height="20"></a>Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.
<a href="https://agentmods.dev/skills/dietrichgebert/ponytail/ponytail-gain"><img src="https://agentmods.dev/badge/skills/dietrichgebert/ponytail/ponytail-gain.svg" alt="Reviewed on agentmods" width="80" height="20"></a>- Socket pass
- Snyk pass
- NVIDIA SkillSpector pass
What it costs to keep this loaded
Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.
| Model | Per session | Once invoked |
|---|---|---|
| Fable 5.1 | $0.00034 | $0.00456 |
| Opus 5 | $0.00017 | $0.00228 |
| Sonnet 5 | $0.00007 | $0.00091 |
| Haiku 4.5 | $0.00003 | $0.00046 |
Grade A, and why
ponytail-gain scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 11d ago.
A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.
Nothing flagged
None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.
Copies of this mod
3 near-identical copies found in the catalogue:
- ponytail-gain — 100% identical, 0 lines differ
- ponytail-gain — 100% identical, 0 lines differ
- ponytail-gain — 100% identical, 0 lines differ
What it actually says
Ponytail Gain
Display this scoreboard when invoked. One-shot: do NOT change mode, write flag files, or persist anything.
The figures are the published benchmark medians (5 everyday tasks: email
validator, debounce, CSV sum, countdown timer, rate limiter; three models:
Haiku, Sonnet, Opus). They are measured, not computed from the current repo.
Source: benchmarks/ and the README.
Scoreboard
Render plain ASCII bars. The bar length shows the measured range; the label carries the exact figure:
ponytail gain benchmark median · 5 tasks · 3 models
Lines of code no-skill ████████████████████ 100%
ponytail ██▌················· 6–20% ▼ 80–94%
Cost no-skill ████████████████████ 100%
ponytail █████▌·············· 23–53% ▼ 47–77%
Speed ponytail ▸ 3–6× faster
This repo: /ponytail-debt (shortcuts you deferred)
/ponytail-audit (what's still cuttable)
Honesty boundary
These are benchmark medians, not this repo. NEVER print a per-repo savings
number ("you saved X lines/tokens here"): the unbuilt version was never
written, so there is no real baseline to subtract from in a live repo. The
only real per-repo figures come from /ponytail-debt (a counted ledger), and
this card points there instead of inventing one.
Boundaries
One-shot display. Edits nothing, changes no mode. "stop ponytail" or "normal mode": revert.
What this file has done since we first saw it
Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.
- 11d ago First seen · 48 lines · 34 tokens per session scan A 6268baa13052
ponytail-gain is a skill published in the GitHub repository DietrichGebert/ponytail (134,118 stars, last pushed 3d ago), licensed MIT. It adds 34 tokens to every session and 456 once invoked, about $0.0002 per session on Opus 5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-30.
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