diagram

diagram is a command for coding agents from tractorjuice/arc-kit. It costs 14 tokens per session (13,236 once invoked), scanned A, original, no licence file.

A command that generates software architecture diagrams with Mermaid or PlantUML C4. These are text-based diagram tools, and C4 is a way to show software structure at different levels.

In plain words
What is it for?
Use it to document services, components, and their relationships in an architecture overview.
Why use it?
It helps teams explain system structure visually and keep those diagrams close to the project documentation.

Command

Installs and runs on its own, but its text points at files inside its plugin — anything it tells you to read at a ${CLAUDE_PLUGIN_ROOT} path is only there once the plugin is installed. Installing the plugin gets both.

Part of the arckit plugin — 75 commands, 31 agents, 10 plugins 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 commands/tractorjuice/arc-kit/diagram
Clone the repo
git clone --depth 1 https://github.com/tractorjuice/arc-kit

Or install arckit, the plugin that ships this one along with the rest of its 75 commands, 31 agents, 10 plugins.

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 diagram

README.md
[![agentmods](https://agentmods.dev/badge/commands/tractorjuice/arc-kit/diagram.svg)](https://agentmods.dev/commands/tractorjuice/arc-kit/diagram)
Your own site
<a href="https://agentmods.dev/commands/tractorjuice/arc-kit/diagram"><img src="https://agentmods.dev/badge/commands/tractorjuice/arc-kit/diagram.svg" alt="Measured on agentmods" height="20"></a>
Per session 14 Only the description is in the session, so the agent can decide to use it. The body loads when it is invoked.
When invoked 13,236 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 $0.00014 $0.13236
Opus 5 $0.00007 $0.06618
Sonnet 5 $0.00003 $0.02647
Haiku 4.5 $0.00001 $0.01324

Measured today against content hash 563b80e97908, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

diagram 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 today.

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-claude/commands/diagram.md · 1,331 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. today Changed 563b80e97908
  2. yesterday First seen · 1,331 lines · 14 tokens per session scan A 4343672b3377

Subscribe to this mod's changes

diagram is a command published in the GitHub repository tractorjuice/arc-kit (2,219 stars, last pushed today), with no licence file. It adds 14 tokens to every session and 13,236 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 2026-09-03.