DiagramMCP Server

DiagramMCP is a server that generates dynamic diagrams using Mermaid syntax, covering flowcharts, sequence diagrams, class diagrams, ER diagrams, Gantt charts, and architecture diagrams. It helps you visualize software designs and workflows quickly, export diagrams for documentation, and validate syntax to catch errors early.

How to use

To use DiagramMCP, connect a client that supports MCP servers and issue diagram-generation requests through the MCP protocol. You can create diagrams by choosing the type you need (flowchart, sequence, class, ER, Gantt, or architecture), supply the required structure (nodes, participants, entities, components, etc.), and receive Mermaid code that you can render with Mermaid tools. Use the available tooling to validate diagrams before rendering and export diagrams to SVG, PNG, PDF, or HTML as needed.

How to install

Prerequisites: Python is installed on your machine.

Step 1: Install dependencies.

pip install -r requirements.txt

Step 2: Run the MCP server.

python app.py

Configuration

To integrate DiagramMCP with Claude Desktop or other MCP clients, use the MCP configuration to point to the local Python server. The following example shows how to register a stdio MCP server with the command to start the Python application and the path to the main script.

{
  "mcpServers": {
    "diagrammcp": {
      "command": "python",
      "args": ["/path/to/diagramMCP/app.py"]
    }
  }
}

Notes and tips

• The server runs on stdio transport by default, which means it is designed to be launched as a local process and communicated with through standard input and output.
• If you need to run it in a container or remote environment, you can adapt the configuration to point to the same Python script.

Examples of diagram generation

You can generate diagrams such as flowcharts, sequence diagrams, class diagrams, ER diagrams, Gantt charts, and architecture diagrams by using the corresponding tools in your MCP client. Each tool accepts structured inputs to define nodes, relationships, and visuals, then returns Mermaid code ready for rendering.

Available tools

create_flowchart

Generates flowchart diagrams for process flows and decision trees.

create_sequence_diagram

Generates sequence diagrams for API interactions and system communications.

create_class_diagram

Generates UML class diagrams for object-oriented design.

create_er_diagram

Generates Entity-Relationship diagrams for database design.

create_gantt_chart

Generates Gantt charts for project planning and scheduling.

create_architecture_diagram

Generates system architecture diagrams showing components and interactions.

validate_diagram

Validates Mermaid diagram syntax and provides error feedback.

export_diagram

Provides export instructions for rendering diagrams in multiple formats.