Get Mermaid diagram syntax, types, and examples via mermaid-mcp-server (npx)

Recipe: Query Mermaid syntax docs and examples via mermaid-mcp-server

Server: mermaid-mcp-server v1.0.8 (npm) Launch: npx -y mermaid-mcp-server (stdio, NDJSON framing) Auth: none Dependencies: none (bundles Mermaid docs)

Important: this is a reference server, NOT a renderer

This server provides structured Mermaid documentation — diagram types, syntax rules, and annotated examples. It does NOT render diagrams to images. Use it as a context source when writing Mermaid code (similar to how Context7 serves library docs).

Tool inventory (4 tools)

Supported diagram types

flowchart, sequenceDiagram, classDiagram, stateDiagram, entityRelationshipDiagram, userJourney, gantt, and more (13+ types from the Mermaid docs corpus).

Verified trace

list_diagrams — returns all diagram types as structured JSON, 1ms:

→ tools/call list_diagrams {}

← 1ms  [
  { type: "flowchart", name: "Flowchart", description: "..." },
  { type: "sequenceDiagram", name: "Sequence Diagram", description: "..." },
  { type: "classDiagram", name: "Class Diagram", description: "..." },
  { type: "stateDiagram", name: "State Diagram", description: "..." },
  { type: "entityRelationshipDiagram", name: "Entity Relationship Diagram", description: "..." },
  { type: "userJourney", name: "User Journey", description: "..." },
  ...
]

get_diagram_examples: flowchart — returns full Markdown documentation with annotated mermaid-example code blocks:

→ tools/call get_diagram_examples { diagramType: "flowchart" }

← 2ms  "# Flowcharts - Basic Syntax\n\nFlowcharts are composed of **nodes**
  (geometric shapes) and **edges** (arrows or lines)...\n\n### A node (default)
  \n\n```mermaid-example\nflowchart LR\n    id\n```\n\n### A node with text..."
  (full Mermaid flowchart docs, ~15KB)

Use case

When an agent needs to write Mermaid syntax (e.g., for documentation generation, PR descriptions, architecture diagrams), it can query this server for correct syntax and examples rather than relying on training data or web searches. Fast (1–2ms), offline-capable, always up-to-date with the bundled Mermaid version.