composer-coding-excellence

composer-coding-excellence is a cursor rule for Cursor from madebyaris/cursor-composer-rules. It costs 21 tokens per session (1,539 once invoked), scanned A, original, MIT.

A set of coding rules for making careful, focused changes that match the existing project. It tells the assistant to inspect related code, avoid unrelated edits, and verify its work.

In plain words
What is it for?
Use it when writing or modifying code, especially when matching project conventions and checking types, tests, or other relevant verification.
Why use it?
It reduces accidental changes, inconsistent style, invented interfaces, and fixes that are not tested.

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/madebyaris/cursor-composer-rules/composer-coding-excellence
Clone the repo
git clone --depth 1 https://github.com/madebyaris/cursor-composer-rules

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.

agentmods badge for composer-coding-excellence

README.md
[![agentmods](https://agentmods.dev/badge/rules/madebyaris/cursor-composer-rules/composer-coding-excellence.svg)](https://agentmods.dev/rules/madebyaris/cursor-composer-rules/composer-coding-excellence)
Your own site
<a href="https://agentmods.dev/rules/madebyaris/cursor-composer-rules/composer-coding-excellence"><img src="https://agentmods.dev/badge/rules/madebyaris/cursor-composer-rules/composer-coding-excellence.svg" alt="Measured on agentmods" height="20"></a>
Per session 21 Only the description is in the session, so the agent can decide to use it. The body loads when it is invoked.
When invoked 1,539 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 $0.00021 $0.01539
Opus 5 $0.00010 $0.00770
Sonnet 5 $0.00004 $0.00308
Haiku 4.5 $0.00002 $0.00154

Measured 3d ago against content hash b925bbd49a1c, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

composer-coding-excellence 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 3d 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/composer-coding-excellence.mdc · 137 lines

How it starts

The opening of the file, as written. The whole thing — 137 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Composer coding excellence

Use whenever you are writing or modifying code. The goal is craftsmanship: changes that look like they were written by the person who wrote the surrounding file.

The editing mindset

You are a careful surgeon, not an enthusiastic remodeler.

  1. Read the file end-to-end (or at least the function plus its callers and tests) before editing.
  2. Mirror the file's style: naming, imports, error handling, type rigor, docstring tone.
  3. Make the smallest diff that achieves the goal. Unrelated improvements are a separate task.
  4. Run the verification that matches the change: types, lints, the relevant test, a manual probe.
  5. Re-read your diff as if reviewing someone else's PR before submitting.

Convention matching is not optional

The codebase's existing patterns are the default. Deviate only with a stated reason.

  • If the file uses camelCase, don't introduce snake_case.
  • If errors are returned as values, don't throw exceptions.
  • If imports are grouped, group yours.
  • If functions are pure, keep yours pure.
  • If the project tests with framework X, don't introduce framework Y.
  • If the project has a logger, use it — don't console.log.

When you must break convention, say so explicitly in the change description.

Style governance

Default to matching the file you are editing. Do not impose your preferred style or "modernize" code the user did not ask to change.

Signal Action
Security, correctness, data loss, broken invariants Fix in the task scope; explain in the change summary
Violates documented project standard (eslint config, ADR, README) Follow the documented standard, not the nearest bad example
Local inconsistency only (var next to const, mixed patterns) Match the file you are editing; optionally one-line note
Widespread anti-pattern (e.g. string SQL, secrets in repo) Do not mass-fix; flag + offer a follow-up plan slice
User asked "clean this up" / "modernize" Allowed; still smallest vertical slice + verification

Read the full file on GitHub · 137 lines

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. 3d ago First seen · 137 lines · 21 tokens per session scan A b925bbd49a1c

Subscribe to this mod's changes

composer-coding-excellence is a cursor rule published in the GitHub repository madebyaris/cursor-composer-rules (3 stars, last pushed 15d ago), licensed MIT. It adds 21 tokens to every session and 1,539 once invoked, about $0.0001 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.