ponytail

ponytail is a cursor rule for Cursor from tatemz/habitica-mcp. It costs 260 tokens per session, scanned A, original, MIT.

A set of coding rules called Ponytail’s “lazy senior developer” mode, where lazy means avoiding unnecessary work while keeping important safety checks.

In plain words
What is it for?
It is for deciding whether code needs to be written, choosing existing tools when possible, keeping solutions small, and requiring checks for non-trivial logic.
Why use it?
It helps prevent needless code, abstractions, dependencies, boilerplate, and files.

Cursor rule for Cursor

Written for Cursor: installed under .cursor/.

Good fit It is for deciding whether code needs to be written, choosing existing tools when possible, keeping solutions small, and requiring checks for non-trivial logic.

Compare 6 cursor rules from other repositories ↓
Install with agentmods
npx agentmods add rules/tatemz/habitica-mcp/ponytail
Install

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.

Clone the repo
git clone --depth 1 https://github.com/tatemz/habitica-mcp

Made for: Cursor.

Wrote 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.

agentmods badge for ponytail

README.md
[![agentmods](https://agentmods.dev/badge/rules/tatemz/habitica-mcp/ponytail/github.svg)](https://agentmods.dev/rules/tatemz/habitica-mcp/ponytail)
Your own site
<a href="https://agentmods.dev/rules/tatemz/habitica-mcp/ponytail"><img src="https://agentmods.dev/badge/rules/tatemz/habitica-mcp/ponytail/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.

agentmods 80×15 button for ponytail

Your own site · 80×15
<a href="https://agentmods.dev/rules/tatemz/habitica-mcp/ponytail"><img src="https://agentmods.dev/badge/rules/tatemz/habitica-mcp/ponytail.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 260 This file is loaded in full into every session.
When invoked 260 The same file — it is already loaded in full.
Security scan A 0 findings. A grade says what 26 rules found in the file — not that it is safe.
Origin original No closer match found in the catalogue.
Token cost

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.

ModelPer sessionOnce invoked
Fable 5.1 $0.00260 $0.00260
Opus 5 $0.00130 $0.00130
Sonnet 5 $0.00052 $0.00052
Haiku 4.5 $0.00026 $0.00026

Measured 10d ago against content hash 9c47ccda5069, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-10, from the pricing page.

Security

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 10d 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.

.cursor/rules/ponytail.mdc · 29 lines

What it actually says

Ponytail, Lazy Senior Dev Mode

Lazy means efficient, not careless. The best code is the code never written.

Before writing code, stop at the first rung that holds:

  1. Does this need to be built at all? (YAGNI)
  2. Does the standard library already do this? Use it.
  3. Does a platform feature cover it? Use it.
  4. Does an installed dependency solve it? Use it.
  5. Can this be one line? Make it one line.
  6. Only then: write the minimum code that works.

Rules:

  • No abstractions that were not explicitly requested or forced by real duplication.
  • No new dependency if a current dependency or Node can do the job.
  • No boilerplate nobody asked for.
  • Deletion over addition. Boring over clever. Fewest files possible.
  • Ask when a request is bigger than its value: "Do you actually need X, or does Y cover it?"
  • Not lazy about secrets, data loss, trust boundaries, deterministic tests, or MCP protocol correctness.

Non-trivial logic leaves one runnable check behind. Trivial one-liners do not need ceremony.

Changes

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.

  1. 10d ago First seen · 29 lines · 260 tokens per session scan A 9c47ccda5069

Subscribe to this mod's changes

ponytail is a cursor rule published in the GitHub repository tatemz/habitica-mcp (0 stars, last pushed 1mo ago), licensed MIT. It adds 260 tokens to every session, about $0.0013 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.