diagram-design

An agent skill that draws diagrams as one self-contained HTML + SVG file, in your brand.45 diagram types. No shadows. No Mermaid slop.

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Install · What it makes · Quickstart · Match your brand · Import · Export · Contributing

npx skills add cathrynlavery/diagram-design

Ask your agent in plain words:

• "Make me an architecture diagram of my app: frontend, backend, database, Redis cache."
• "I need a quadrant showing Q2 projects by impact vs effort."
• "Give me a sequence of a bearer call with token refresh on 401."
• "Onboard diagram-design to https://yoursite.com" (pulls your palette and fonts so every diagram after this one matches your site)

The agent picks the type, states its plan, and writes one .html file you can open by double-clicking.

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Install

Works with any host that reads Agent Skills, including Cursor, Claude Code, Codex, Qoder, GitHub Copilot, Gemini CLI, Cline, Windsurf and Amp:

npx skills add cathrynlavery/diagram-design

In Claude Code, the plugin marketplace gets you updates and the slash commands:

/plugin marketplace add cathrynlavery/diagram-design
/plugin install diagram-design@diagram-design

Official builds come only from this repository. LittleMight, Cathryn Lavery's company, publishes the plugin directory listings; a listing under any other name is an unofficial copy. PRIVACY.md lists what the skill sends over the network.

Claude Code: turn on auto-update

After installing, run /plugin, open Marketplaces, select diagram-design, and choose Enable auto-update. Claude Code disables auto-update by default for third-party marketplaces; after this toggle, it refreshes the marketplace and installed plugin in the background after startup. Run /reload-plugins when prompted, or let the next session load the update.

Cursor, Cline, Gemini CLI, Windsurf, Amp, Zed, Warp, Roo, Kilo and other Agent Skills hosts

The cross-agent skills CLI resolves this repository, detects skills/diagram-design/SKILL.md, and installs the whole skill (references/, assets/, scripts/) into every host root you select, including Cursor's:

npx skills add cathrynlavery/diagram-design

When the selected roots resolve to more than one skills directory, the CLI asks for an installation method and recommends Symlink: one canonical copy, linked into each root, so a later update reaches all of them at once. Pass --copy for independent copies per host instead. A selection that resolves to a single directory is copied, because the distinction is immaterial there. Where symlinks are unavailable (Windows without Developer Mode) the CLI falls back to copies and reports which roots it copied.

This is a standalone install, separate from the marketplaces below: it does not follow marketplace updates automatically. Pull merged updates with npx skills update diagram-design. It also installs the Agent Skill only, so the /export-diagram, /import-mermaid, /import-plantuml, /profile, and /doctor command surfaces stay with the native packages. On a host that has one of the marketplaces below, prefer the marketplace.

One-time migration: an existing standalone npx skills add copy will not start following the Codex marketplace automatically. Remove that standalone copy, then use the Codex marketplace commands. Likewise, uninstall a personal Cowork copy and reinstall Diagram Design from your organization's marketplace. Future marketplace version bumps then flow through each client's native update path.

Codex

codex plugin marketplace add cathrynlavery/diagram-design
codex plugin add diagram-design@diagram-design

Codex refreshes configured Git marketplaces at startup. To fetch immediately, run codex plugin marketplace upgrade diagram-design and start a new session.

Qoder

Clone the repository, validate the native plugin, and install it locally:

git clone https://github.com/cathrynlavery/diagram-design.git
qoder plugins validate ./diagram-design
qoder plugins install ./diagram-design
qoder plugins list

Qoder loads the canonical skills/diagram-design/ tree and the shared command definitions directly; no Qoder-specific copy is maintained. For Qoder IDE, build a bounded ZIP from the tracked plugin surfaces and import it through Extensions → Plugins → Add Plugins → Upload Plugin:

git -C diagram-design archive --format=zip \
  --output=../diagram-design-qoder.zip HEAD \
  .qoder-plugin commands skills LICENSE

Start a new task after installing or updating the plugin.

GitHub Copilot

copilot plugin marketplace add cathrynlavery/diagram-design
copilot plugin install diagram-design@diagram-design

Copilot installs the shared Diagram Design skill plus its doctor, export, import, and profile capabilities from the existing repository marketplace. Confirm discovery with copilot skill list (or /skills in an interactive session), then ask for a diagram in natural language. To fetch a merged update, run copilot plugin marketplace update diagram-design, then copilot plugin update diagram-design@diagram-design.

Factory Droid

droid plugin marketplace add https://github.com/cathrynlavery/diagram-design
droid plugin install diagram-design@diagram-design --scope user

Droid tracks Git plugins by commit rather than the manifest's display version. To fetch a merged update, run droid plugin marketplace update diagram-design, then droid plugin update diagram-design@diagram-design --scope user, and start a new session.

Claude Cowork (organization marketplace)

Organization GitHub marketplaces currently require a private or internal repository, so first mirror this public repository into one owned by your organization. In Organization settings → Plugins, choose Add plugin → GitHub, connect that mirror, and enable Sync automatically from the marketplace menu. Automatic sync runs when a pull request containing a plugin version bump is merged to the mirror's default branch; direct pushes do not trigger the webhook. Install Diagram Design from the resulting organization marketplace.

Pi

pi install https://github.com/cathrynlavery/diagram-design

Run /reload in an open Pi session. Pi makes the skill available for matching diagram requests; use /skill:diagram-design to invoke it explicitly. Pi also loads the /export-diagram, /import-mermaid, /import-excalidraw, /import-plantuml, /profile, and /doctor prompt templates. The unpinned Git install is intentional: Pi has no automatic package refresh, so run pi update --extensions to pull merged updates.

Kiro

Import the Agent Skill from the repository subdirectory URL:

https://github.com/cathrynlavery/diagram-design/tree/main/skills/diagram-design

Kiro copies imported skills into .kiro/skills/ for a workspace or ~/.kiro/skills/ globally, so re-import the URL to pick up updates. Custom agents that declare resources should include skill://diagram-design/**/SKILL.md.

OpenCode

Copy or symlink skills/diagram-design/ to .opencode/skills/diagram-design in a project or ~/.config/opencode/skills/diagram-design globally. OpenCode has no Diagram Design marketplace package; copied installs update only when you replace the directory from a newer checkout.

Editable install (customize the style guide in a clone)

Managed installs are convenient, but changes to references/style-guide.md may be replaced by package updates. Saved profiles in ~/.diagram-design/profiles/ survive updates, and projects with a .diagram-design marker are unaffected. Clone the repo and install the local path if you plan to customize the working style guide directly:

git clone git@github.com:cathrynlavery/diagram-design.git ~/code/diagram-design

# Pi: register the checkout as a local package
pi install ~/code/diagram-design

# Claude Code: symlink the inner skill
ln -s ~/code/diagram-design/skills/diagram-design ~/.claude/skills/diagram-design

# Other Agent Skills hosts: create only the roots you use
mkdir -p ~/.agents/skills ~/.cursor/skills ~/.cline/skills ~/.kiro/skills ~/.config/opencode/skills ~/.copilot/skills
ln -s ~/code/diagram-design/skills/diagram-design ~/.agents/skills/diagram-design
ln -s ~/code/diagram-design/skills/diagram-design ~/.cursor/skills/diagram-design
ln -s ~/code/diagram-design/skills/diagram-design ~/.cline/skills/diagram-design
ln -s ~/code/diagram-design/skills/diagram-design ~/.kiro/skills/diagram-design
ln -s ~/code/diagram-design/skills/diagram-design ~/.config/opencode/skills/diagram-design
ln -s ~/code/diagram-design/skills/diagram-design ~/.copilot/skills/diagram-design

The shared skill lives at skills/diagram-design/. Pi discovers it through the repo's standard skills/ package directory; Claude Code, GitHub Copilot, Codex, Factory Droid, Cursor, and other Agent Skills-compatible tools use the same files.

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How it compares

	Mermaid / PlantUML	draw.io / Excalidraw	Diagram Design
You make it by	Writing text	Dragging shapes by hand	Describing it to your agent
Layout	Automatic	Manual	Placed by the agent on a 4px grid, with CI checks for overlaps and clipping