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.
git clone --depth 1 https://github.com/wintermeyer/cursor-rails-rulesWrote 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/rules/wintermeyer/cursor-rails-rules/testing-faker)<a href="https://agentmods.dev/rules/wintermeyer/cursor-rails-rules/testing-faker"><img src="https://agentmods.dev/badge/rules/wintermeyer/cursor-rails-rules/testing-faker/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/rules/wintermeyer/cursor-rails-rules/testing-faker"><img src="https://agentmods.dev/badge/rules/wintermeyer/cursor-rails-rules/testing-faker.svg" alt="Reviewed on agentmods" width="80" height="20"></a>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 | $0.01298 |
| Opus 5.5 | $0.00000 | $0.00519 |
| Sonnet 5.5 | $0.00000 | $0.00260 |
| Haiku 4.5 | $0.00000 | $0.00130 |
Grade A, and why
testing-faker 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 2mo 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.
How it starts
The opening of the file, as written. The whole thing — 201 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Faker Standards
Use the faker gem to generate test data when it makes sense.
Install the faker gem if it is not already included in the Gemfile.
Usage Guidelines
- When to Use Faker
- All personal information (names, emails, addresses)
- All business data (products, prices, descriptions)
- All dates and times (except fixed dates)
- All content (articles, comments, posts)
- All identifiers (except fixed IDs)
- When NOT to Use Faker
- Primary keys or foreign keys
- Fixed enumeration values
- Status flags or boolean fields
- Test-specific values needed for assertions
Common Patterns
- Personal Information
FactoryBot.define do
factory :user do
first_name { Faker::Name.first_name }
last_name { Faker::Name.last_name }
email { Faker::Internet.email(name: "#{first_name} #{last_name}") }
phone { Faker::PhoneNumber.phone_number }
date_of_birth { Faker::Date.birthday(min_age: 18, max_age: 65) }
bio { Faker::Lorem.paragraph(sentence_count: 2) }
end
end
- Business Data
FactoryBot.define do
factory :product do
name { Faker::Commerce.product_name }
description { Faker::Lorem.paragraph }
price { Faker::Commerce.price(range: 10.0..1000.0) }
sku { Faker::Barcode.ean }
category { Faker::Commerce.department }
brand { Faker::Company.name }
end
factory :company do
name { Faker::Company.name }
catch_phrase { Faker::Company.catch_phrase }
industry { Faker::Company.industry }
website { Faker::Internet.url }
founded_at { Faker::Date.between(from: 20.years.ago, to: 1.year.ago) }
end
end
- Content Generation
FactoryBot.define do
factory :article do
title { Faker::Lorem.sentence(word_count: 4) }
content { Faker::Lorem.paragraphs(number: 3).join("\n\n") }
excerpt { Faker::Lorem.paragraph }
author_name { Faker::Name.name }
published_at { Faker::Time.between(from: 1.year.ago, to: Time.current) }
trait :with_tags do
after(:build) do |article|
article.tags = [
Faker::Lorem.word,
Faker::Lorem.word,
Faker::Lorem.word
].uniq
end
end
end
factory :comment do
content { Faker::Lorem.paragraph }
author_name { Faker::Internet.username }
author_email { Faker::Internet.email }
ip_address { Faker::Internet.ip_v4_address }
end
end
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.
- 2mo ago First seen · 201 lines · 0 tokens per session scan A d2f876d2d6d5
testing-faker is a cursor rule published in the GitHub repository wintermeyer/cursor-rails-rules (37 stars, last pushed 1y ago), licensed MIT. It costs nothing until one of its globs matches a file; then it loads 1,298 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.
Other cursor rules, from other repositories
fuzzing
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testing-and-quality
The testcomprehensive.py provides systematic testing of all 31 MCP tools.
smoke-monkey-tester
Smoke tests for core functionality and monkey/chaos tests aiming to break the system with randomized inputs. / TR: Sistemin temel fonksiyonlarını kontrol eden smoke testler ve rastgele girdilerle sistemi çökertmeyi hedefleyen monkey/chaos testleri.
testing
Testing conventions for Ion Design System using Jest and Angular Testing Library.
STAGE_S5_TEST_POINTS
A staged workflow for turning approved requirements into a complete list of test points. It checks required earlier documents and records any requirement that has no matching test point.
pre-flight-check
Mandatory fail-fast quality gate — run Typecheck, Lint, Test, and Security Audit sequentially before declaring any task done or committing code.