excalidraw-diagram

excalidraw-diagram is a skill for Claude Code from bdmorin/the-no-shop. It costs 48 tokens per session (5,892 once invoked), scanned B, a copy of excalidraw-diagram, MIT.

A tool for creating Excalidraw diagrams, which are hand-drawn-style diagrams stored as JSON files and rendered as images.

In plain words
What is it for?
Use it to draw architecture diagrams, flowcharts, process maps, and other visual arguments, then check the rendered result.
Why use it?
It helps turn workflows, systems, and other ideas into visual explanations that are easier to inspect and share.

Skill for Claude Code

Written for Claude Code: shipped in a Claude Code plugin. Also seen: mentions Claude Code.

Part of the excalidraw-diagram plugin — 1 skill shipped together

Good fit Use it to draw architecture diagrams, flowcharts, process maps, and other visual arguments, then check the rendered result.

Compare 6 skills from other repositories ↓
Install with agentmods
npx agentmods add skills/bdmorin/the-no-shop/excalidraw-diagram
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.

Any agent
npx skills add bdmorin/the-no-shop --skill excalidraw-diagram
Clone the repo
git clone --depth 1 https://github.com/bdmorin/the-no-shop

Made for: Claude Code.

Or install excalidraw-diagram, the plugin that ships this one along with the rest of its 1 skill.

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 excalidraw-diagram

README.md
[![agentmods](https://agentmods.dev/badge/skills/bdmorin/the-no-shop/excalidraw-diagram/github.svg)](https://agentmods.dev/skills/bdmorin/the-no-shop/excalidraw-diagram)
Your own site
<a href="https://agentmods.dev/skills/bdmorin/the-no-shop/excalidraw-diagram"><img src="https://agentmods.dev/badge/skills/bdmorin/the-no-shop/excalidraw-diagram/github.svg" alt="Measured on agentmods" height="20"></a>

Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.

agentmods 80×15 button for excalidraw-diagram

Your own site · 80×15
<a href="https://agentmods.dev/skills/bdmorin/the-no-shop/excalidraw-diagram"><img src="https://agentmods.dev/badge/skills/bdmorin/the-no-shop/excalidraw-diagram.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 48 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 5,892 The whole file, excluding the scripts and references it only reads on demand.
Security scan B 1 finding. A grade says what 26 rules found in the file — not that it is safe.
Origin 94% copy Near-identical to another mod 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 $0.00048 $0.05892
Opus 5 $0.00024 $0.02946
Sonnet 5 $0.00010 $0.01178
Haiku 4.5 $0.00005 $0.00589

Measured 12d ago against content hash 4208fb81e919, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-12, from the pricing page.

Security

Grade B, and why

excalidraw-diagram scanned grade B with 1 finding 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 12d 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.

Subtle steeringmediumPrompt injection

Instructions that bias recommendations or shape behaviour without the user noticing.

- **Don't write a Python generator script.** The templating and coordinate math seem helpful but introduce a layer of indirection that makes debugging harder. Hand-crafted JSON with descriptive IDs is more maintainable.
Origin

This is a copy

94% identical to excalidraw-diagram — 190 lines differ, which has more behind it and is treated as the original. This page carries a canonical link to it rather than competing with it.

plugins/excalidraw-diagram/skills/excalidraw-diagram/SKILL.md · 613 lines

How it starts

The opening of the file, as written. The whole thing — 613 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Excalidraw Diagram Creator

Generate .excalidraw JSON files that argue visually, not just display information.

Locating Plugin Files

This skill's reference files and rendering tools are in the references/ directory at the plugin root. To find them:

Glob: **/excalidraw-diagram/references/color-palette.md

Read the first match's parent directory to locate all reference files:

  • color-palette.md -- Single source of truth for colors and brand styles
  • element-templates.md -- JSON templates for each Excalidraw element type
  • json-schema.md -- Element types, common properties, binding format
  • render_excalidraw.py -- Python/Playwright renderer (.excalidraw -> PNG)
  • share_excalidraw.py -- Upload to excalidraw.com, returns shareable URL (E2E encrypted)
  • render_template.html -- HTML template used by the renderer
  • pyproject.toml -- Python dependencies (playwright, cryptography)

Read color-palette.md before generating any diagram. It is the single source of truth for all color choices -- shape fills, strokes, text colors, evidence artifact backgrounds, everything.

Customization

To make this skill produce diagrams in your own brand style, edit color-palette.md. Everything else in this file is universal design methodology and Excalidraw best practices.


Core Philosophy

Diagrams should ARGUE, not DISPLAY.

A diagram isn't formatted text. It's a visual argument that shows relationships, causality, and flow that words alone can't express. The shape should BE the meaning.

The Isomorphism Test: If you removed all text, would the structure alone communicate the concept? If not, redesign.

The Education Test: Could someone learn something concrete from this diagram, or does it just label boxes? A good diagram teaches -- it shows actual formats, real event names, concrete examples.


Depth Assessment (Do This First)

Before designing, determine what level of detail this diagram needs:

Simple/Conceptual Diagrams

Use abstract shapes when:

  • Explaining a mental model or philosophy
  • The audience doesn't need technical specifics
  • The concept IS the abstraction (e.g., "separation of concerns")

Read the full file on GitHub · 613 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. 12d ago First seen · 613 lines · 48 tokens per session scan B 4208fb81e919

Subscribe to this mod's changes

excalidraw-diagram is a skill published in the GitHub repository bdmorin/the-no-shop (10 stars, last pushed 5mo ago), licensed MIT. It adds 48 tokens to every session and 5,892 once invoked, about $0.0002 per session on Opus 5. A static security scan graded it B with 1 finding (subtle steering). It is 94% identical to excalidraw-diagram, differing in 190 lines, and is treated as a copy.

Related

Other skills, from other repositories