agent-design

A set of commands for designing the structure and operating rules of an AI agent.

In plain words
What is it for?
It is for choosing architecture patterns and defining tool contracts, memory, orchestration, and guardrails.
Why use it?
It helps decide how an agent uses tools, remembers information, coordinates work, and stays within limits.

Command

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 commands/tractorjuice/arc-kit/agent-design
Clone the repo
git clone --depth 1 https://github.com/tractorjuice/arc-kit
Per session 17 Only the description is in the session, so the agent can decide to use it. The body loads when it is invoked.
When invoked 4,336 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. Scan, not verified.
Origin unknown 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 $0.00017 $0.04336
Opus 5 $0.00009 $0.02168
Sonnet 5 $0.00003 $0.00867
Haiku 4.5 $0.00002 $0.00434

Measured 2d ago against content hash 0739b966f1be, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

agent-design 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.

plugins/arckit-agent-architecture/commands/agent-design.md · 411 lines

The source is not reproduced here

No licence file

A repository with no LICENSE is all rights reserved by default, so the body is not copied here. The metadata, the measurements and the link are.

Read it on GitHub

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 · 411 lines · 17 tokens per session scan A 0739b966f1be

Subscribe to this mod's changes

agent-design is a command published in the GitHub repository tractorjuice/arc-kit (2,208 stars, last pushed 11d ago), with no licence file. It adds 17 tokens to every session and 4,336 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 2026-08-30.