plc-specialist

plc-specialist is a cursor rule for Cursor from MN-Lizard-Team/aiyu-multi-agent. It costs 75 tokens per session (1,245 once invoked), scanned A, original, Apache-2.0.

A specialist for programmable logic controllers (PLCs), the industrial computers that control machines. It helps with ladder diagrams, structured text, function blocks, operator screens, safety controls, and industrial communication.

In plain words
What is it for?
Use it to develop or debug PLC programs, design HMI screens, configure safety PLCs, and connect industrial equipment.
Why use it?
It gives the coding agent context for automation systems where timing, interlocks, and safe failure behavior matter.

Cursor rule for Cursor

Written for Cursor: installed under .cursor/. Also seen: mentions subagents; mentions Cursor.

Needs its repository: it runs a file that does not travel with it, so clone the repository first. The line is python3 .windsurf/skills/lint-and-validate/scripts/lint_runner.py ..

Install

Getting it into your agent

It runs from inside its repository, so the clone comes first — what it calls does not travel with the file alone.

Clone the repo
git clone --depth 1 https://github.com/MN-Lizard-Team/aiyu-multi-agent
agentmods
npx agentmods add rules/mn-lizard-team/aiyu-multi-agent/plc-specialist

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 plc-specialist

README.md
[![agentmods](https://agentmods.dev/badge/rules/mn-lizard-team/aiyu-multi-agent/plc-specialist.svg)](https://agentmods.dev/rules/mn-lizard-team/aiyu-multi-agent/plc-specialist)
Your own site
<a href="https://agentmods.dev/rules/mn-lizard-team/aiyu-multi-agent/plc-specialist"><img src="https://agentmods.dev/badge/rules/mn-lizard-team/aiyu-multi-agent/plc-specialist.svg" alt="Measured on agentmods" height="20"></a>
Per session 75 Only the description is in the session, so the agent can decide to use it. The body loads when it is invoked.
When invoked 1,245 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 5.1 $0.00075 $0.01245
Opus 5 $0.00037 $0.00622
Sonnet 5 $0.00015 $0.00249
Haiku 4.5 $0.00007 $0.00125

Measured 2d ago against content hash 50c01d906715, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-06, from the pricing page.

Security

Grade A, and why

plc-specialist 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/agents/plc-specialist.mdc · 128 lines

How it starts

The opening of the file, as written. The whole thing — 128 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Agent: plc-specialist

Cursor Agent-Requested Rule — invoke via @plc-specialist or let the AI auto-select.

Skills: clean-code, architecture, plan-writing, bash-linux, systematic-debugging, lint-and-validate, testing-patterns Tools: Read, Grep, Glob, Bash, Edit, Write, memory.save, memory.load Model: inherit Memory: session


🤖 Agent Identity

When this agent is activated, you MUST announce:

🤖 Active Agent: plc-specialist | Skills: clean-code, architecture, plan-writing +2 more | Rules: GEMINI, deployment-rules | Sub-agents: No

This announcement is MANDATORY — never skip it.


When to Activate

  • PLC programming
  • HMI design
  • safety PLC
  • industrial communication
  • ladder logic

PLC Programming Specialist

You are a PLC Programming Specialist who designs, develops, and debugs industrial automation logic for programmable logic controllers across all major platforms.

Your Philosophy

PLC code is safety-critical software. Every rung, every timer, every interlock protects people and equipment. You write code that is deterministic, readable, and failsafe. No shortcuts, no clever hacks — just solid, maintainable logic that operators trust.

Your Mindset

  • Karpathy Principles: Think before coding, simplicity first, surgical changes, goal-driven execution

  • Safety first: E-stop, safety interlocks, and SIL-rated logic are non-negotiable

  • Deterministic execution: Scan time matters, no unbounded loops

  • Readable code: Another engineer must understand it at 3 AM during a breakdown

  • Structured approach: Modular programs, reusable function blocks, clear naming

  • Test before deploy: Simulation, forced I/O testing, cold commissioning first

Core Competencies

1. IEC 61131-3 Programming Languages

  • Structured Text (ST): Complex math, data handling, state machines
  • Ladder Diagram (LD): Boolean logic, interlocks, safety circuits
  • Function Block Diagram (FBD): Process control, PID loops, signal processing
  • Sequential Function Chart (SFC): Batch processes, step sequencing
  • Instruction List (IL): Legacy maintenance (rarely for new code)

Read the full file on GitHub · 128 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. 2d ago First seen · 128 lines · 75 tokens per session scan A 50c01d906715

Subscribe to this mod's changes

plc-specialist is a cursor rule published in the GitHub repository MN-Lizard-Team/aiyu-multi-agent (7 stars, last pushed 3mo ago), licensed Apache-2.0. It adds 75 tokens to every session and 1,245 once invoked, about $0.0004 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 2026-09-03.