principle-checker

principle-checker is a cursor rule for coding agents from yunbow/ai-dev-os-plugin-cursor. It costs 28 tokens per session (236 once invoked), scanned A, original, MIT.

A code-review rule set that checks whether changes follow high-level design principles, such as giving each module one responsibility and keeping parts properly separated.

In plain words
What is it for?
For reviewing code structure, dependency direction, naming, separation of concerns, and ease of testing.
Why use it?
It catches architectural problems that detailed style or guideline checks may miss.

Cursor rule

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/yunbow/ai-dev-os-plugin-cursor/principle-checker
Clone the repo
git clone --depth 1 https://github.com/yunbow/ai-dev-os-plugin-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 principle-checker

README.md
[![agentmods](https://agentmods.dev/badge/rules/yunbow/ai-dev-os-plugin-cursor/principle-checker.svg)](https://agentmods.dev/rules/yunbow/ai-dev-os-plugin-cursor/principle-checker)
Your own site
<a href="https://agentmods.dev/rules/yunbow/ai-dev-os-plugin-cursor/principle-checker"><img src="https://agentmods.dev/badge/rules/yunbow/ai-dev-os-plugin-cursor/principle-checker.svg" alt="Measured on agentmods" height="20"></a>
Per session 28 Only the description is in the session, so the agent can decide to use it. The body loads when it is invoked.
When invoked 236 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 $0.00028 $0.00236
Opus 5 $0.00014 $0.00118
Sonnet 5 $0.00006 $0.00047
Haiku 4.5 $0.00003 $0.00024

Measured 3d ago against content hash 8302ae71a27f, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

principle-checker 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.

rules/principle-checker.mdc · 28 lines

What it actually says

You are the AI Dev OS L2 Principle Checker.

Role

Verify that code changes align with L2 principles (design principles, architecture principles). Evaluate higher-level design decisions that L3 guidelines (specific rules) cannot detect.

Check Perspectives

  1. Single Responsibility Principle: Does the changed module carry multiple responsibilities?
  2. Dependency Direction: Do dependencies point inward → outward (Clean Architecture)?
  3. Separation of Concerns: Are UI / business logic / data access properly separated?
  4. Naming Intent: Do names accurately express domain concepts?
  5. Testability: Is the design easy to test?

Output

  • Alignment with principles: ✅ / ⚠️ / ❌
  • Rationale for misalignment (with quotes from L2 files)
  • Improvement suggestions (at the principle level — do not suggest specific implementations)

Language

Respond in the same language as the project's .cursorrules file.

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 · 28 lines · 28 tokens per session scan A 8302ae71a27f

Subscribe to this mod's changes

principle-checker is a cursor rule published in the GitHub repository yunbow/ai-dev-os-plugin-cursor (2 stars, last pushed 5mo ago), licensed MIT. It adds 28 tokens to every session and 236 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.