Harvester MCP Server

The MCP server allows the Rancher AI agent to securely retrieve or update Harvester resources in Harvester clusters. It expects the Rancher token in a header, which the agent will always provide for authentication.

Note

This repo was originally forked from https://github.com/rancher/rancher-ai-mcp and is now dedicated to Harvester / SUSE Virtualization.

Overview

This Model Context Protocol (MCP) server provides a secure bridge between the Rancher AI agent and Harvester clusters, enabling AI-powered cluster management through a standardized tool interface. The server runs as a Kubernetes deployment within the Rancher environment and exposes tools for resource inspection, modification, and cluster operations.

Architecture

Package Structure

• cmd/ - CLI commands and server initialization

  • serve.go - HTTP/TLS server setup with dynamic listener support
  • root.go - Root command configuration

• pkg/client/ - Kubernetes client abstraction

  • Dynamic client wrapper with cluster ID resolution
  • Rancher API integration for cluster management
  • Support for both local and downstream cluster operations

• pkg/toolsets/virtualization/ - Harvester / SUSE Virtualization tools

  • toolsets.go - Central registry for tool collections
  • VM, image, volume, network, and node operations

• pkg/response/ - Response formatting utilities

  • Structured text and content generation for MCP responses

• pkg/converter/ - Data transformation utilities

  • Group/Version/Resource (GVR) conversion helpers

TLS & Security

The server supports two modes:

1. TLS Mode (Production): Uses Rancher's dynamic listener with auto-generated certificates

   • Certificates stored as Kubernetes secrets
   • Automatic cert rotation and renewal
   • Client certificate authentication support
   • TLS 1.2+ with secure cipher suites

2. Insecure Mode (Development): Plain HTTP for local testing

   • Enabled via --insecure flag or INSECURE_SKIP_TLS=true

Available Tools

Each tool is exposed through the MCP protocol and can be invoked by the Rancher AI agent:

Tool	Description
listVirtualMachines	Lists VirtualMachine resources on a Harvester / SUSE Virtualization cluster
listVirtualMachineImages	Lists VirtualMachineImage resources on a Harvester / SUSE Virtualization cluster
listVolumes	Lists storage volumes (PersistentVolumeClaims) on a Harvester / SUSE Virtualization cluster
listVirtualMachineNetworks	Lists NetworkAttachmentDefinition resources on a Harvester / SUSE Virtualization cluster
listClusterNetworks	Lists ClusterNetwork resources on a Harvester / SUSE Virtualization cluster
listNodes	Lists nodes (hosts) on a Harvester / SUSE Virtualization cluster
inspectVolume	Inspects a storage volume (PersistentVolumeClaim), including Longhorn details when applicable
createVirtualMachineImage	Creates a VirtualMachineImage resource by downloading from a URL
createVirtualMachine	Creates a VirtualMachine from an existing image
createVirtualMachinePlan	Returns the manifest that would be submitted to create a VirtualMachine, without creating it
deleteVirtualMachine	Deletes a VirtualMachine
deleteVirtualMachinePlan	Returns the resource that would be deleted, without actually removing it

Configuration

Command-line Flags

--port <int>              Port to listen on (default: 9092)
--insecure                Skip TLS verification (default: false)