dsh-mermaid
Render Mermaid code blocks as SVG diagrams in DeepSeek Harness Web, with diagram/code switching, streaming support, dark mode, strict security, and npm/GitHub installation.
- Stars
- 0
- Language
- JavaScript
- Created
- Aug 23, 2026
- Updated
- Aug 23, 2026
Introduction
dsh-mermaid
简体中文 | English
Render Mermaid fenced code blocks in DeepSeek Harness Web as SVG diagrams with a Diagram / Code toggle. The plugin supports streaming responses, dark mode, and automatic fallback to source code when rendering fails.
Features
- Supports
mermaid,mermaidjs, andmmdfenced code blocks - Works with the DSH/Shiki plain fallback, where code elements may not have a language class
- Bundles the exact Mermaid
11.17.0release and requires no runtime CDN - Uses Mermaid's
securityLevel: strict - Enhances only
<pre><code>blocks and ignores inline code - Prevents stale asynchronous renders from overwriting newer streaming content
Install
If dsh is available globally, install the stable npm release with:
dsh plugin --profile web add -w dsh-mermaid
Without a global dsh command, invoke DSH through npx:
npx.cmd --yes @deepseek-ai/dsh plugin --profile web add -w dsh-mermaid
DSH installs the package through pnpm, detects its dsh.bundle declaration, and automatically adds dsh-mermaid to the web profile bundle list. Restart DSH Web or refresh the page after installation.
Install the latest GitHub source
npx.cmd -y github:MrmoLabs/dsh-mermaid install
This runs the repository's dsh-mermaid installer, which asks DSH to install the GitHub source into the web profile. GitHub installation builds the package during installation. If pnpm reports that it blocked a build script, add the exact package key shown by pnpm to allowBuilds in the profile's pnpm-workspace.yaml, then run the command again. Prefer the npm release for normal use.
Update and uninstall
Update the npm release:
dsh plugin --profile web update -w dsh-mermaid
Uninstall:
dsh plugin --profile web remove -w dsh-mermaid
Restart DSH Web after updating or uninstalling.
Usage
Ask a model to output a Mermaid fenced code block:
```mermaid
flowchart LR
A[Code] --> B[Diagram]
```
The code block receives Diagram / Code controls and opens in diagram view by default.
Develop from source
Node.js 22.19 or later is required.
npm.cmd install
npm.cmd run check
npm.cmd run build
dsh plugin --profile web add -w .
Build output is written to lib/ and registered with the DSH client module loader as dsh-mermaid. DSH resolves the relative installation path against the current plugin checkout.
For manual local development, the built package can also be copied to:
C:\Users\<username>\.dsh\profiles\web\node_modules\dsh-mermaid
Never commit the complete .dsh directory. It may contain conversations and credentials.
Release checks
npm.cmd run check
npm.cmd run build
npm.cmd pack --dry-run
git status --short
git diff --cached