joint CLAUDE.md

A development guide for JointJS, a JavaScript and TypeScript library for building diagrams and visual applications. It describes the project as a monorepo, meaning one repository that contains several related packages.

In plain words
What is it for?
Use it when installing dependencies, building distribution files, running package or browser tests, checking types, linting, or working on a specific JointJS package.
Why use it?
It gathers the required tools, package layout, build commands, and different test commands, making work in the multi-package project easier to navigate.

Instructions file

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 instructions/clientio/joint/claude-md
Clone the repo
git clone --depth 1 https://github.com/clientIO/joint
Per session 1,220 This file is loaded in full into every session.
When invoked 1,220 The same file — it is already loaded in full.
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 $0.01220 $0.01220
Opus 5 $0.00610 $0.00610
Sonnet 5 $0.00244 $0.00244
Haiku 4.5 $0.00122 $0.00122

Measured 2d ago against content hash c846690b9999, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

joint CLAUDE.md 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.

CLAUDE.md · 122 lines

How it starts

The opening of the file, as written. The whole thing — 122 lines — stays where its author put it; the contents beside it link to each section on GitHub.

CLAUDE.md

This file provides guidance to Claude Code (claude.ai/code) when working with code in this repository.

Project Overview

JointJS is a JavaScript/TypeScript diagramming library for building visual and no-code/low-code applications. It's a Yarn workspace monorepo with multiple packages.

Stack: Node 22.14.0, Yarn 4.18.0, TypeScript 5.8 (5.9 in joint-react), Grunt (build), QUnit/Karma/Mocha/Jest (testing)

Common Commands

# Install dependencies
yarn install

# Build distribution files (runs Grunt)
yarn dist

# Run all tests (QUnit + Jest + TypeScript checks)
yarn test

# Run specific test types
yarn test-server       # Server-side tests (Node.js)
yarn test-client       # Client-side tests (Browser with Karma)
yarn test-ts           # TypeScript type definition tests
yarn test-e2e          # End-to-end tests (Puppeteer)

# Linting
yarn lint              # Check all packages
yarn lint-fix          # Auto-fix errors

# Build bundles
yarn build
yarn build-bundles

Running Single Tests

For joint-react Jest tests:

cd packages/joint-react
yarn jest --testPathPatterns="ComponentName"

Architecture

Monorepo Packages (/packages)

  • @joint/core - Main diagramming library (MVC architecture, SVG rendering)
  • @joint/react - React bindings and hooks (Rollup + esbuild, Storybook)
  • @joint/layout-directed-graph - Graph layout algorithms
  • @joint/layout-msagl - Microsoft MSAGL layout integration
  • @joint/shapes-general - General-purpose diagram shapes
  • @joint/eslint-config - Shared ESLint configuration

Core Library Structure (/packages/joint-core/src)

The library follows an MVC pattern:

  • mvc/ - Base MVC components: Model, View, Collection, Events, Dom
  • dia/ - Diagramming API built on MVC:
    • Graph.mjs - Graph data structure and cell management
    • Paper.mjs - SVG canvas and rendering engine
    • Element.mjs / ElementView.mjs - Diagram nodes
    • Link.mjs / LinkView.mjs - Connections between elements
  • g/ - Geometry library (points, lines, curves, polygons, matrices)
  • V/ - Vectorizer for SVG manipulation
  • connectors/ - Link path strategies (line, curve, bezier, jumpover)
  • routers/ - Link routing algorithms (manhattan, orthogonal, metro)
  • anchors/ - Connection point anchors on elements
  • highlighters/ - Visual highlighting mechanisms
  • linkTools/, elementTools/ - Interactive manipulation tools
  • shapes/ - Built-in shapes (standard)
  • layout/ - Built-in layouts (port, port label)
  • alg/ - Graph algorithms (DFS, BFS, shortest path)

Read the full file on GitHub · 122 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 · 122 lines · 1,220 tokens per session scan A c846690b9999

Subscribe to this mod's changes

joint CLAUDE.md is an instructions file published in the GitHub repository clientIO/joint (5,366 stars, last pushed 4d ago), licensed MPL-2.0. It adds 1,220 tokens to every session, about $0.0061 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.