principle-checker

principle-checker is an agent for coding agents from yunbow/ai-dev-os-plugin-claude-code. It costs 33 tokens per session (245 once invoked), scanned A, original, MIT.

A design-principle checker that reviews code changes against higher-level software design principles.

In plain words
What is it for?
Use it to review changes for separation of concerns, dependency direction, meaningful naming, single responsibility, and testability, with improvement advice at the design level.
Why use it?
It catches architectural problems that detailed coding rules may miss, such as mixed responsibilities, poorly directed dependencies, or difficult-to-test design.

Agent

Part of the ai-dev-os plugin — 11 skills, 3 agents, 3 hooks shipped together

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

Or install ai-dev-os, the plugin that ships this one along with the rest of its 11 skills, 3 agents, 3 hooks.

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/agents/yunbow/ai-dev-os-plugin-claude-code/principle-checker.svg)](https://agentmods.dev/agents/yunbow/ai-dev-os-plugin-claude-code/principle-checker)
Your own site
<a href="https://agentmods.dev/agents/yunbow/ai-dev-os-plugin-claude-code/principle-checker"><img src="https://agentmods.dev/badge/agents/yunbow/ai-dev-os-plugin-claude-code/principle-checker.svg" alt="Measured on agentmods" height="20"></a>
Per session 33 Only the description is in the session, so the agent can decide to use it. The body loads when it is invoked.
When invoked 245 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 $0.00033 $0.00245
Opus 5 $0.00016 $0.00122
Sonnet 5 $0.00007 $0.00049
Haiku 4.5 $0.00003 $0.00024

Measured 4d ago against content hash 3a7c0e128386, 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 4d 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.

agents/principle-checker.md · 34 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)
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. 4d ago First seen · 34 lines · 33 tokens per session scan A 3a7c0e128386

Subscribe to this mod's changes

principle-checker is an agent published in the GitHub repository yunbow/ai-dev-os-plugin-claude-code (2 stars, last pushed 5mo ago), licensed MIT. It adds 33 tokens to every session and 245 once invoked, about $0.0002 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.

Related

Other agents, from other repositories