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 agentmods add rules/kleosr/kleosrules/ponytailgit clone --depth 1 https://github.com/kleosr/kleosrulesWhat 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 | $0.00231 | $0.00231 |
| Opus 5 | $0.00115 | $0.00115 |
| Sonnet 5 | $0.00046 | $0.00046 |
| Haiku 4.5 | $0.00023 | $0.00023 |
Grade A, and why
ponytail 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 2d 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.
What it actually says
Native Lean
Smallest diff. Zero prose comments. No registered lean hook.
Ladder
- No code
- Reuse (Grep)
- Stdlib
- Platform
- Installed dep
- One-liner
- Minimum (soft ~80; split before 120; hard 300; >700 rewrite modules ≤300)
Quality
Match 1–2 siblings before Write. Named exports. Early return. Nesting ≤2. No any / blind casts. No dead code or empty catch.
Tools
Read, Grep, Glob, Write, StrReplace, EditNotebook, Delete.
Shell: builds, tests, git. before_shell.sh denies Shell source-write.
Split
Over roof: Write new modules, StrReplace original to imports, Grep callers. Never Shell sed.
Procedure
Complex or architecture: Read ~/.cursor/skills/ponytail/SKILL.md
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.
- 2d ago First seen · 31 lines · 231 tokens per session scan A 4a72afbc762f
ponytail is a cursor rule published in the GitHub repository kleosr/kleosrules (2 stars, last pushed 3d ago), licensed MIT. It adds 231 tokens to every session, about $0.0012 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 2026-08-31.
Other cursor rules, from other repositories
nextjs
Rules for Next.js projects (App Router and Pages Router).
php
Rules applied when working in PHP files (incl. Laravel, Symfony, WordPress).
ruby
Rules applied when working in Ruby files (incl. Rails).
svelte
Rules for Svelte / SvelteKit components.
vue
Rules for Vue (2 and 3) single-file components.
shell
Rules for shell scripts (bash, zsh, sh, PowerShell).