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-helpgit 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-help)<a href="https://agentmods.dev/skills/dietrichgebert/ponytail/ponytail-help"><img src="https://agentmods.dev/badge/skills/dietrichgebert/ponytail/ponytail-help/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-help"><img src="https://agentmods.dev/badge/skills/dietrichgebert/ponytail/ponytail-help.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 | $0.00022 | $0.00717 |
| Opus 5 | $0.00011 | $0.00358 |
| Sonnet 5 | $0.00004 | $0.00143 |
| Haiku 4.5 | $0.00002 | $0.00072 |
Grade A, and why
ponytail-help 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 9d 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
8 near-identical copies found in the catalogue:
- ponytail-help — 100% identical, 0 lines differ
- ponytail-help — 91% identical, 7 lines differ
- ponytail-help — 91% identical, 7 lines differ
- ponytail-help — 91% identical, 7 lines differ
- ponytail-help — 86% identical, 6 lines differ
- ponytail-help — 83% identical, 13 lines differ
- ponytail-help — 83% identical, 13 lines differ
- ponytail-help — 81% identical, 14 lines differ
How it starts
The opening of the file, as written. The whole thing — 71 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Ponytail Help
Display this reference card when invoked. One-shot, do NOT change mode, write flag files, or persist anything.
Levels
| Level | Trigger | What change |
|---|---|---|
| Lite | /ponytail lite |
Build what's asked, name the lazier alternative in one line. |
| Full | /ponytail |
The ladder enforced: YAGNI → stdlib → native → one line → minimum. Default. |
| Ultra | /ponytail ultra |
YAGNI extremist. Deletion before addition. Challenges requirements before building. |
Level sticks until changed or session end.
Skills
| Skill | Trigger | What it does |
|---|---|---|
| ponytail | /ponytail |
Lazy mode itself. Simplest solution that works. |
| ponytail-review | /ponytail-review |
Over-engineering review: L42: yagni: factory, one product. Inline. |
| ponytail-audit | /ponytail-audit |
Whole-repo over-engineering audit: ranked list of what to delete. |
| ponytail-debt | /ponytail-debt |
Harvest ponytail: shortcut comments into a tracked ledger. |
| ponytail-gain | /ponytail-gain |
Measured-impact scoreboard: less code, less cost, more speed. |
| ponytail-help | /ponytail-help |
This card. |
Codex uses @ponytail, @ponytail-review, and @ponytail-help; Claude Code
and OpenCode use the slash-command forms above (OpenCode ships all six as
slash commands).
Deactivate
Say "stop ponytail" or "normal mode". Resume anytime with /ponytail.
/ponytail off also works.
Configure Default Mode
Default mode = full, auto-active every session. Change it:
Environment variable (highest priority):
export PONYTAIL_DEFAULT_MODE=ultra
Config file (~/.config/ponytail/config.json, Windows: %APPDATA%\ponytail\config.json):
{ "defaultMode": "lite" }
Set "off" to disable auto-activation on session start, activate manually
with /ponytail when wanted.
Resolution: env var > config file > full.
Update
Enable auto-update once: open /plugin, go to Marketplaces, pick ponytail, Enable auto-update. Claude Code then pulls new versions at startup (run /reload-plugins when it prompts). Manual refresh: /plugin marketplace update ponytail then /reload-plugins.
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.
- 9d ago First seen · 71 lines · 22 tokens per session scan A be2bab79e073
ponytail-help is a skill published in the GitHub repository DietrichGebert/ponytail (131,289 stars, last pushed yesterday), licensed MIT. It adds 22 tokens to every session and 717 once invoked, about $0.0001 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.
Other skills, from other repositories
archetype-authoring
This skill should be used when the user asks to "create", "edit", "specialize", "review / remediate", "write the rationale for", "translate / localise", or "fix the ADL syntax of" an openEHR archetype (including "this archetype won't parse / won't validate"), or to import a CKM archetype into the workspace for reuse.…
openehr-assistant
This skill should be used when a conversation touches openEHR outside a task owned by a dedicated skill — e.g. "what is an archetype?", "how do openEHR templates work?", "which composition category fits this data?", "find me a guide on X", "where do I start with openEHR modeling?" — or names openEHR concepts (ADL…
template-authoring
This skill should be used when the user asks to "create a template", "design a template", "constrain archetypes into a template", "review a template", "categorise a dataset with CGEM", "should this be persistent, episodic or event?", "split this form across compositions", "sketch a template from this form / which…
composition-builder
This skill should be used when the user asks to "build a composition", "create a composition", "validate a composition", "convert a composition", or "generate FLAT/STRUCTURED/CANONICAL format". Covers building openEHR compositions in all simplified formats and guiding their validation and format conversion (against a…
demographic-modeling
This skill should be used when the user asks to "design a demographic model", "model a person/organisation/role", "design party relationships", "plan identity structures", or "work with demographic archetypes". Covers designing openEHR demographic models using the PARTY hierarchy, roles, capabilities, relationships…
aql-authoring
This skill should be used when the user asks to "write an AQL query", "optimize an AQL query", "review AQL", or "query openEHR data" — the multi-step authoring/optimization workflow for AQL (Archetype Query Language) over openEHR clinical data. For a one-off explanation of an existing query or a single AQL…