EVE-NG MCP Server

Instructions

Implementation Reference

• eveng_mcp_server/tools/node_management.py:190-258 (handler)

  The main handler function for the 'add_node' MCP tool. It is decorated with @mcp.tool() for automatic registration, validates input via AddNodeArgs, prepares node parameters, calls the underlying eveng_client.add_node(), and returns formatted TextContent results.

  @mcp.tool()
  async def add_node(arguments: AddNodeArgs) -> list[TextContent]:
      """
      Add a node to a lab.
  
      This tool adds a new node to an existing lab with the specified
      template, configuration, and positioning. The node will be created
      but not automatically started.
      """
      try:
          logger.info(f"Adding node to lab: {arguments.lab_path}")
  
          if not eveng_client.is_connected:
              return [TextContent(
                  type="text",
                  text="Not connected to EVE-NG server. Use connect_eveng_server tool first."
              )]
  
          # Prepare node parameters
          node_params = {
              "name": arguments.name,
              "node_type": arguments.node_type,
              "left": arguments.left,
              "top": arguments.top,
              "delay": arguments.delay,
              "console": arguments.console,
              "config": arguments.config,
          }
  
          # Add optional parameters if specified
          if arguments.ethernet is not None:
              node_params["ethernet"] = arguments.ethernet
          if arguments.serial is not None:
              node_params["serial"] = arguments.serial
          if arguments.image is not None:
              node_params["image"] = arguments.image
          if arguments.ram is not None:
              node_params["ram"] = arguments.ram
          if arguments.cpu is not None:
              node_params["cpu"] = arguments.cpu
  
          # Add node
          result = await eveng_client.add_node(arguments.lab_path, arguments.template, **node_params)
  
          if result.get('status') == 'success':
              node_id = result.get('data', {}).get('id', 'Unknown')
              return [TextContent(
                  type="text",
                  text=f"Successfully added node to lab!\n\n"
                       f"Lab: {arguments.lab_path}\n"
                       f"Template: {arguments.template}\n"
                       f"Node ID: {node_id}\n"
                       f"Name: {arguments.name or f'Node{node_id}'}\n"
                       f"Type: {arguments.node_type}\n"
                       f"Position: ({arguments.left}%, {arguments.top}%)\n\n"
                       f"Node created successfully. Use start_node to power it on."
              )]
          else:
              return [TextContent(
                  type="text",
                  text=f"Failed to add node: {result.get('message', 'Unknown error')}"
              )]
  
      except Exception as e:
          logger.error(f"Failed to add node: {e}")
          return [TextContent(
              type="text",
              text=f"Failed to add node: {str(e)}"
          )]

• eveng_mcp_server/tools/node_management.py:35-51 (schema)

  Pydantic model defining the input schema and validation for the add_node tool arguments.

  class AddNodeArgs(BaseModel):
      """Arguments for add_node tool."""
      lab_path: str = Field(description="Full path to the lab (e.g., /lab_name.unl)")
      template: str = Field(description="Node template name (e.g., 'vios', 'linux', 'iol')")
      name: str = Field(default="", description="Node name (optional, auto-generated if empty)")
      node_type: str = Field(default="qemu", description="Node type (qemu, iol, dynamips)")
      left: int = Field(default=50, description="Position from left (percentage, 0-100)")
      top: int = Field(default=50, description="Position from top (percentage, 0-100)")
      delay: int = Field(default=0, description="Seconds to wait before starting node")
      console: str = Field(default="telnet", description="Console type (telnet, vnc)")
      config: str = Field(default="Unconfigured", description="Config state (Unconfigured, Saved)")
      ethernet: Optional[int] = Field(default=None, description="Number of ethernet interfaces")
      serial: Optional[int] = Field(default=None, description="Number of serial interfaces")
      image: Optional[str] = Field(default=None, description="Specific image to use")
      ram: Optional[int] = Field(default=None, description="RAM in MB")
      cpu: Optional[int] = Field(default=None, description="Number of CPUs")

• eveng_mcp_server/tools/__init__.py:24-25 (registration)

  Within register_tools(), calls register_node_tools() which defines and registers the add_node tool (along with other node tools) by executing the decorated function definitions.

  # Node management tools
  register_node_tools(mcp, eveng_client)

• eveng_mcp_server/server.py:53-54 (registration)

  Top-level call to register_tools() in the MCP server initialization, which triggers the registration chain for all tools including add_node.

  register_tools(self.mcp, self.eveng_client)