A set of Ruby coding conventions aligned with the project's RuboCop configuration. RuboCop is a tool that checks Ruby code for agreed formatting and style rules.

Use it when adding or editing Ruby code, choosing method arguments, handling missing hash keys, structuring controllers, and simplifying conditional logic.

It gives the coding agent consistent rules for writing and reviewing Ruby code, reducing style disagreements and common design problems.

ruby-style — Cursor rule for Cursor by romkey/I2C-Directory

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/romkey/I2C-Directory

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.

README.md

[![agentmods](https://agentmods.dev/badge/rules/romkey/i2c-directory/ruby-style/github.svg)](https://agentmods.dev/rules/romkey/i2c-directory/ruby-style)

Your own site

<a href="https://agentmods.dev/rules/romkey/i2c-directory/ruby-style"><img src="https://agentmods.dev/badge/rules/romkey/i2c-directory/ruby-style/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.

Your own site · 80×15

<a href="https://agentmods.dev/rules/romkey/i2c-directory/ruby-style"><img src="https://agentmods.dev/badge/rules/romkey/i2c-directory/ruby-style.svg" alt="Reviewed on agentmods" width="80" height="20"></a>

Per session 0 Nothing until a file matches its globs; then the whole rule loads.

When invoked 254 The whole file, excluding the scripts and references it only reads on demand.

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.

Model	Per session	Once invoked
Fable 5.1	$0.00000	$0.00254
Opus 5.5	$0.00000	$0.00102
Sonnet 5.5	$0.00000	$0.00051
Haiku 4.5	$0.00000	$0.00025

Measured 1mo ago against content hash e1347223fa26, method: parsed. Prices are Anthropic first-party input rates as of 2026-10-07, from the pricing page.

Security

Grade A, and why

ruby-style 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 1mo 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/ruby-style.mdc · 43 lines

What it actually says

Ruby Style

Follow the project's .rubocop.yml conventions:

Strings: Use single quotes unless interpolation is needed
Line length: Max 120 characters
Frozen string literal: Do not add # frozen_string_literal: true comments
Target Ruby: 3.3 — use modern Ruby syntax (pattern matching, endless methods where clear)
New cops: All new RuboCop cops are enabled

Patterns

Prefer Hash#fetch with defaults over Hash#[] when a missing key is possible
Use keyword arguments for methods with 3+ parameters
Keep controllers thin — extract logic to service objects or model methods
Use ActiveRecord::Enum for status fields
Guard clauses over nested conditionals

# ❌
def process(member)
  if member.active?
    if member.paid?
      do_work(member)
    end
  end
end

# ✅
def process(member)
  return unless member.active?
  return unless member.paid?

  do_work(member)
end

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.

1mo ago First seen · 43 lines · 0 tokens per session scan A e1347223fa26

Subscribe to this mod's changes

ruby-style is a cursor rule published in the GitHub repository romkey/I2C-Directory (11 stars, last pushed 11d ago), licensed MIT. It costs nothing until one of its globs matches a file; then it loads 254 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 2026-08-30.

Languages Ruby arduino esp32 esp8266 i2c i2c-bus twowire

ruby-style

Getting it into your agent

Wrote this? Show the measurements

What it costs to keep this loaded

Grade A, and why

Nothing flagged

What it actually says

Ruby Style

Patterns

What this file has done since we first saw it

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