Desktop Hypervisor MCP

One provider-neutral MCP server for the desktop hypervisors: VirtualBox, VMware Fusion, and VMware Workstation. Nine tools, ~1,800 context tokens, full coverage of what its two predecessor servers did in ~5,600.

It succeeds virtualbox-mcp-server (that history is preserved on the predecessor-virtualbox branch) and the never- released vmware-fusion-mcp-server, folding both into one capability-based surface.

Design

• Capability-based, not lowest-common-denominator. Providers advertise what they can actually do (provider action=list): guest exec, OVA import/export, linked clones, pre-boot guestinfo injection, DHCP-lease IP discovery, ISO mastering… Unsupported operations fail by naming the missing capability, not with a provider error.

• Intent, not mechanism. "Ensure the cluster nodes share a network the host can reach" is expressible on both families; "create a host-only interface" is not. The neutral tools express intent; provider-native mechanism stays reachable, unabstracted, through execute_command.

• Artifacts resolve per provider. The same image name gives each hypervisor the artifact it can actually import — Talos's vmware-*.ova vs virtualbox-*.ova, Vagrant's vmware_desktop vs virtualbox boxes, Microsoft's per-hypervisor dev VM — keyed on (image, provider family, host arch).

Related MCP server: vmware-mcp

Tools

With one hypervisor installed it is selected automatically; with several, the ambiguity is surfaced, never guessed.

Image catalog

artifact action=catalog lists maintained images: Talos (appliance and metal ISO), Ubuntu (cloud image and Vagrant), Debian, Fedora, Rocky, Alma, openSUSE, FreeBSD, Kali, TurnKey, the Windows dev VM, plus vagrant:org/box passthrough to the whole registry. Downloads are sha256-verified wherever the publisher provides a digest (GitHub release assets always do); unverified sources say so loudly. Vagrant boxes are fetched for the right provider and auto-extracted to their importable machine file. The cache lives in ~/.hypervisor-images (HV_IMAGE_DIR overrides).

Prerequisites

• VirtualBox (VBoxManage) and/or VMware Fusion / Workstation (vmrun). Detection is per-call, so a hypervisor installed mid-session is picked up.

• Nothing else: a single static Go binary, no Python, no Node.

Optional, detected at runtime: ovftool enables OVA import/export on VMware; xorriso enables repack_iso.

Building

go build -o desktop-hypervisor-mcp .

Registration with Claude Code

claude mcp add --scope user hypervisor -- /path/to/desktop-hypervisor-mcp

Guest-operation credentials come from the server environment, never from tool parameters:

claude mcp add --scope user hypervisor \
  --env HV_GUEST_USER=vagrant --env HV_GUEST_PASSWORD=vagrant \
  -- /path/to/desktop-hypervisor-mcp

(VMRUN_GUEST_USER/VMRUN_GUEST_PASSWORD are honored for compatibility.)

The server ships usage recipes in the MCP initialize handshake, generated from what was actually detected on the host — a session on a VirtualBox-only machine never pays context for VMware guidance.

Permissions

Per-tool allowlisting in .claude/settings.json keeps prompts meaningful — read-only tools are safe to always-allow:

{
  "permissions": {
    "allow": [
      "mcp__hypervisor__provider",
      "mcp__hypervisor__vm_info",
      "mcp__hypervisor__artifact",
      "mcp__hypervisor__snapshot"
    ]
  }
}

Keep mutating tools (vm_lifecycle, execute_command) behind prompts unless you accept unattended VM mutation.

Related projects

• talos-mcp-server — Talos/Kubernetes orchestration; consumes this server for node provisioning and stays deliberately hypervisor-agnostic.