efficiency-audit

A set of rules for finding performance problems in code that uses NumPy, CuPy, Dask, or Numba, Python tools for numerical and parallel computing.

In plain words
What is it for?
It is for reviewing source code for performance anti-patterns in projects using those libraries.
Why use it?
It helps locate coding patterns that may make numerical workloads use too much time or memory.

Cursor rule for Cursor

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.

agentmods
npx agentmods add rules/brendancol/xarray-spatial-skills/efficiency-audit
Clone the repo
git clone --depth 1 https://github.com/brendancol/xarray-spatial-skills

Made for: Cursor.

Per session 0 Nothing until a file matches its globs; then the whole rule loads.
When invoked 593 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. Scan, not verified.
Origin unknown 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 $0.00000 $0.00593
Opus 5 $0.00000 $0.00296
Sonnet 5 $0.00000 $0.00119
Haiku 4.5 $0.00000 $0.00059

Measured 2d ago against content hash be7d6d536eaf, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

efficiency-audit 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.

.cursor/rules/efficiency-audit.mdc · 48 lines

The source is not reproduced here

No licence file

A repository with no LICENSE is all rights reserved by default, so the body is not copied here. The metadata, the measurements and the link are.

Read it on GitHub

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. 2d ago First seen · 48 lines · 0 tokens per session scan A be7d6d536eaf

Subscribe to this mod's changes

efficiency-audit is a cursor rule published in the GitHub repository brendancol/xarray-spatial-skills (3 stars, last pushed 1mo ago), with no licence file. It costs nothing until one of its globs matches a file; then it loads 593 tokens. 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.