readme

A project guide containing the coding and testing rules developers should follow in this application.

In plain words
What is it for?
Use it when adding or changing Rails pages and features, writing tests, handling translations, or checking code quality after a change.
Why use it?
It keeps changes consistent with the project, including its languages, styling approach, translations, tests, and required checks.

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/wintermeyer/cursor-rails-rules/readme
Clone the repo
git clone --depth 1 https://github.com/wintermeyer/cursor-rails-rules

Made for: Cursor.

Per session 7 Only the description is in the session, so the agent can decide to use it. The body loads when it is invoked.
When invoked 255 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. Scan, not verified.
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 $0.00007 $0.00255
Opus 5 $0.00003 $0.00128
Sonnet 5 $0.00001 $0.00051
Haiku 4.5 $0.00001 $0.00026

Measured 2d ago against content hash 4b7a1d5e044b, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

readme 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/readme.mdc · 25 lines

What it actually says

You are a senior programmer. Your role is to work with me as a pair programming team. Take care of the following things in case I forget them:

  • When possible we always create at least one happy path test to check the functionality we just implimented or fixed. So if I e.g. create a new page we have to write a basic test that checks that that page answers with a 200 HTTP code.
  • Always use i18n.mdc since this is a multilanguage project.
  • Use Tailwind CSS and avoid plain CSS.

Modify or create the code as requested. After completing the changes, execute the following commands in the terminal:

  1. Run tests to ensure everything still works:
    bin/rails test:all
    
  2. Automatically fix and check Ruby style issues:
     bundle exec rubocop --format github --autocorrect-all
    
  3. If any tests fail:
  • Analyze the errors and attempt to fix them. It doesn't matter if it is old or new code.
  • Modify the necessary code to resolve the failures.
  • Re-run bin/rails test:all to confirm the fix.
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 · 25 lines · 7 tokens per session scan A 4b7a1d5e044b

Subscribe to this mod's changes

readme is a cursor rule published in the GitHub repository wintermeyer/cursor-rails-rules (37 stars, last pushed 1y ago), licensed MIT. It adds 7 tokens to every session and 255 once invoked, about $0.0000 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 2026-08-30.