1-clean-code

A set of general code-quality rules for writing simple, readable software. It covers typing, naming, function and file size, error handling, duplication, and separating different responsibilities.

In plain words
What is it for?
Use it when designing files and functions, organizing code by business area, handling errors, removing duplication, and separating application parts.
Why use it?
It helps prevent tangled code that is hard to understand, test, change, or debug.

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/cmnemoi/cursor-rules/1-clean-code
Clone the repo
git clone --depth 1 https://github.com/cmnemoi/cursor-rules

Made for: Cursor.

Per session 9 Only the description is in the session, so the agent can decide to use it. The body loads when it is invoked.
When invoked 263 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 $0.00009 $0.00263
Opus 5 $0.00005 $0.00131
Sonnet 5 $0.00002 $0.00053
Haiku 4.5 $0.00001 $0.00026

Measured yesterday against content hash adbeebabc2b8, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

1-clean-code 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 yesterday.

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.

general-rules/.cursor/rules/01-standards/1-clean-code.mdc · 39 lines

What it actually says

Code Quality:

  • Maintain strict typing.
  • Disallow untyped values and magic numbers.
  • Use explicit enums for possible values.
  • Avoid double negatives and ensure conditions are self-documenting.
  • Use long, readable variable names reflecting domain concepts.
  • Write the simplest code possible
  • Eliminate duplication (DRY).

Length Limits:

  • Max 20 lines per function : extract until you drop.
  • Max 3 parameters per function.
  • Max 300 lines per file.
  • Max 10 sub-files per folder.

Responsibilities:

  • One responsibility per file.
  • Organize code by domain concepts (e.g., Communications, Player, Action).

Functions:

  • No flag parameters; split into multiple functions if needed.
  • Follow command-query separation.
  • Use verbs for service methods that perform actions.

Errors:

  • Fail fast and throw errors early.
  • Use custom domain errors and translate errors to user language.
  • Log errors in English with error codes.

Code Organization:

  • Follow Ports & Adapters pattern with clear separation between entities, repositories, services, enums, events, listeners, and value objects.
  • Favor composition over inheritance.
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. yesterday First seen · 39 lines · 9 tokens per session scan A adbeebabc2b8

Subscribe to this mod's changes

1-clean-code is a cursor rule published in the GitHub repository cmnemoi/cursor-rules (2 stars, last pushed 1y ago), licensed MIT. It adds 9 tokens to every session and 263 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 2026-08-31.