Claude Code plugin
very-nice-mermaid ships a Claude Code plugin that bundles one skill - also called very-nice-mermaid. It teaches Claude Code to render Mermaid diagrams with the vnm CLI instead of just printing the raw DSL: ASCII inline, a PNG it can look at to check the result, an interactive HTML page, or an SVG for your docs.
Install
In Claude Code, add this repo as a plugin marketplace, then install the plugin:
/plugin marketplace add ZawadzkiB/very-nice-mermaid
/plugin install very-nice-mermaid@very-nice-mermaid
That’s it. The skill activates automatically whenever you ask Claude to render, view, or export a Mermaid diagram - no command to remember. Just ask:
“Render this flowchart so I can see it” · “Turn this sequence diagram into an interactive HTML page” · “Export that state machine as an SVG for my docs”
Requirements: Claude Code and Node ≥ 20 (the skill runs the published CLI via npx very-nice-mermaid, so there’s nothing else to install).
What the skill does
It picks the right output format for what you’re doing:
| You want to… | The skill uses | Result |
|---|---|---|
| See it inline in chat / a markdown file | -f md | ASCII in a fenced block, pasted into the reply |
| Check it actually looks right | -f png then reads the image | Claude renders a PNG and looks at it before presenting |
| Play with it | -f html then opens it | A self-contained interactive page (drag / zoom / pan) |
| Embed it in docs | -f svg | A static, themeable, scalable SVG |
It also relays diagnostics plainly - e.g. if a layout-heavy fallback type (gantt, ER, …) can’t render headlessly from the CLI, it tells you and offers the interactive HTML instead. See the CLI reference for the full option set the skill drives.
Updating
/plugin install reads a local copy of the marketplace, so reinstalling on its own won’t pull a newer version. Refresh the marketplace first:
/plugin marketplace update very-nice-mermaid
/plugin install very-nice-mermaid@very-nice-mermaid
/reload-plugins
Local development
Hacking on the skill itself? Add your local clone as the marketplace instead of the GitHub one (they share the name very-nice-mermaid, so use one or the other):
/plugin marketplace add /path/to/very-nice-mermaid
/plugin install very-nice-mermaid@very-nice-mermaid
After each change, bump version in .claude-plugin/plugin.json (a reload only picks up a new version), then:
/plugin marketplace update very-nice-mermaid
/plugin install very-nice-mermaid@very-nice-mermaid
/reload-plugins
The skill’s source of truth is skills/very-nice-mermaid/SKILL.md.